EpiSensor - KMI Support WIKI
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1. 10 Table 4 Reasomable zero offset voltages oooonnnncccnoncccnonccnnncncnnnncnnnnccnnnos 14 Table 5 R nge sensitivity calculations cosilla 21 Table 6 Typical Cable Resistance Calculation 22 22004 en 35 Table 7 Typical Cable Length Calculation 35 Table 8 ES U Current Requirements 3 u rar 37 Safety Symbols amp Terms The following symbols may appear on Kinemetrics equipment or in this manual marked relevant part of this manual before servicing the instrument This symbol means a low noise earth ground The noted item should be grounded to ensure low noise operation and also to serve as a ground return for EMVRFI and transients Such a ground does not work as a safety ground for protection against electrical shock BEN When you see this symbol pay careful attention Refer to the similarly This symbol means an alternating current AC power line er This symbol means a direct current DC power line derived from an AC power line A This symbol indicates an electrostatic sensitive device ESD meaning a that when handling the marked equipment you should observe all standard precautions for handling such devices These safety related terms appear in this manual Note statements identify information that you should consider before moving to the next instruction or choice Caution statements identify conditions or practices that cou2. Even if the recorder cannot produce a functional test it is still very important that these lines be held at the correct potential The Cal line is not connected to the sensor unless the CCE line is active but to provide the best noise performance it should not be left floating We suggest that the Cal line be grounded to power common when the calibration coil is not in use The CCE line drives a transistor that operates an analog switch that connects the Cal line to the sensor module calibration coil The transistor will turn on the analog switch at voltages between 5 to 12V The transistor is not activated at voltages below 0 5V This means a CMOS driver can drive the line or an open collector output pulled up to 12V A transistor transistor logic TTL level will probably work if the sensor is close to the digitizer It is very important that the CCE line is not enabled when the calibration feature is not in use and that it is not powered when the unit is not powered This is because the Cal line is connected to the sensor coil during the calibration sequence which can result in additional noise The easiest way to prevent problems from the CCE line is to connect it to the power common or the 12V supply To produce a functional test sequence the data logger needs to control both the Cal and the CCE lines The voltage applied to the Cal line should be limited to 10V The sensor should reproduce any signal applied by the digitizer w
3. DOCUMENT 301925 REVISION A POWER CONNECTIONS In a dual supply EpiSensor standard model Positive 12V 15V connects to the red wire m Negative 12V 15V connects to the brown wire Common connects to the single black wire In a single supply EpiSensor optional model 12 15V power connects to the red wire No connection to the brown wire Common connects to the black wire CALIBRATION CONNECTIONS Connect calibration signals to the appropriate outputs on the recorder CONNECTING TO ALTUS EXTERNAL SENSOR INPUT The table below shows which pins the EpiSensor should be connected to on an Altus External Sensor Input Connector Table 2 EpiSensor Outputs to Altus instrument channels nl Altus Instrument Black wie D White wie O Shield wire Pin N Pin P PinR Table 3 EpiSensor Connections to Altus external sensor connector EpiSensor Pigtail Altus External Sensor Connector Outer shield Pin U PGP or instrument case ground Single black wire Pin K power supply common Brown or no connect Pin H negative power EPISENSOR ES U USER GUIDE DocuMENT 301925 REVISION A Read the following section on grounding for additional information Chapter 6 Advanced Installations contains additional information on connecting to recorders grounding etc Grounding the EpiSensor Grounding sensitive instrumentation is a complex problem It is difficult to give universally acceptable solutions for all installat
4. enregistreur connectez l enregistreur en utilisant le systeme d alimentation fourni par Kinemetrics et decrit dans le manuel d utilisation d livr avec l enregistreur Pour fournir une alimentation au EpiSensor vous avez besoin d une source faible bruit 12 15V avec une mise a la terre ad quate et qui remplit les conditions de la reglementation locale OPTION SYST ME D ALIMENTATION FOURNI PAR L UTILISATEUR Si vous fournissez votre syst me d alimentation vous devez vous assurez que le syst me fournit une tension et un courant requis par le EpiSensor Veuillez noter que vous serez seul responsible pour la s curit de votre systeme d alimentation Si vous utilisez le courant du r seau d alimentation principal vous devez vous assurez d installer les mises a la terre ad quates pour tout votre equipement Si vous utilisez vos batteries vous devez vous r f rer aux recommendations fournis par le fournisseurs MISE LA TERRE ET CONNECTION DU CAPTEUR Dans certain cas le capteur EpiSensor est install distance de l enregistreur Dans ces installations il est possible soit a cause d une connection d fectueuse au syst me d alimentation principale o d un fort courant de retour la terre pour une difference de potentiel qui existe SAFETY 9 entre la mise la terre aux deux locations Quand le cable est mise la terre d un cot une tension potentiellement fatale peut exister entre l autr
5. 14 Performing the Zero Adjustment cesccesceseeeceeeseccesneesenteccerteees 14 Note on Full Scale Range nee 15 3 Operating Basics Signal Polarity ns ee e A 18 DocuMENT 301925 REVISION A NA lege beein tea 18 Performing a Functional Test with an Altus Recorder ur ne 18 Sensor Response Test Ip in 19 EpiSensor CORA O EEE er a are 19 Opening the EpiSensor Case anna en 20 Jumper Selectable Options ee ea 20 Setting the Full Scale Range unse 20 Power Supply Options uuasaisiahssunkunlaabeiu nn 23 Calibration Colt e e ns ns ra 23 Closing the EpiSensor Case nenn sen 24 4 Maintenance Recommended Maintenance zarten sehe en 25 Adjust the Accelerometers un naar 25 Complete a Functional Test un nennen sn 25 Calibration ass RS er ee te Sie wil ut fn 25 Desiccant R pl cement rime aus eu intel 26 Troubleshooting and R pair 242 03 RE RE RE Rs 26 5 Reference THEORY OF Operan nase 27 Working Principles iia r E Ea TE aA 28 Features inori oped aid e a a ab 29 Pole Zero Representation of the EpiSensor ooocooccnnoninocononcconnnonancnoncnonccnnnos 29 Polarity Conventi onset isre ches eoe e aes t e aa iS 32 6 Advanced Installations CE Compliant Installations siciliana locas alcatel tada 33 Using EpiSensors with Altus Instruments 33 Th K2 amp Mt Whiney nc loas 33 Ihe Eins sense een ee teen en 34 Makali usina due ee ne nano Re tt nat ane let 34 E
6. DOCUMENT 301925 REVISION A to the sensor Access to the coil for calibration verification is discussed below With non Altus recorders access to the calibration coils is available through the cable The cal coil is enabled by applying a 5 to 12 volt signal to the calibration coil enable line CCE that closes an electronic switch This switch is normally open to prevent noise from entering the system The calibration coil sensitivity is provided in the data sheet of each unit The total resistance to ground of the calibration coil line is about 1710 ohms and the nominal resistance of the calibration coil is 110 ohms The additional resistance of approximately 1600 ohms added in series with the calibration coil is necessary as the coil is driven from a voltage source Closing the EpiSensor Case Caution Potential electrostatic discharge ESD hazard to equipment Wear a grounded wrist strap with impedance of approximately 1 M Q when handling the EpiSensor circuit boards to protect components from damage 1 Inspect the gasket to make sure it is still elastic and is not torn 2 Install gasket and cover over the housing 3 Engage the four 4 40 socket head screws and tighten by hand Note Make sure the gasket completely covers the gap between the cover and enclosure 4 Make sure the gasket is properly installed closing the gap between the cover and enclosure 5 Tighten screws to a torque of 5 6 inch pound 0 56 0 77
7. and may damage the sensor If the voltage is too low the EpiSensor will not attain its full scale output and the data will be corrupted Never supply more than 15 75V to the unit and be sure the connections are the correct polarity The EpiSensor has no protection against reversed polarity connections Reversed power connections will severely damage the instrument The current required for the EpiSensor can be calculated using the table below The supply should be capable of supplying the maximum load for the sensor under operating conditions The quiescent current is the best figure to use for sizing batteries or solar charging systems Table 8 ES U Current Requirements 25 mar Additional current for high gain 6mA output Output Voltage The EpiSensor output is user selectable as is the output amplifier Select the EpiSensor output that matches the recorder input If possible use a EPISENSOR ES U USER GUIDE 37 38 DocuMENT 301925 REVISION A differential input connection for optimum performance Configuring the correct range and output is described in Chapter 3 The output impedance of the EpiSensor is 50 Q to ensure the unit is stable under capacitive loading from a long cable Normally data loggers have an input impedance of 100 kQ or more so the 50Q output impedance is insignificant Calibration Sequence To produce a functional test sequence the recorder must control the Cal and CCE line to the EpiSensor
8. the feet and floor ensure accurate reproduction of ground motion This is not the case at high acceleration levels which can cause an unsecured instrument to move relative to the ground Keep a permanent record of the orientation This information is crucial to the proper analysis of EpiSensor data Use the supplied mounting kit to attach the sensor to the mounting surface The kit includes two heavy duty wedge type expansion anchor studs with 1 4 20 thread and a nut washer unit Decide on the location of the EpiSensor keeping in mind the working mounting dimensions Important The anchor studs are 2 1 4 long and more than 1 2 must remain above the slab Follow all recommended safety precautions when using power tools We recommend wearing safety glasses while drilling DOCUMENT 301925 REVISION A Figure 2 EpiSensor mounting dimensions Wal ES U orientation x we i f Electrical connection ES U mounting slots Allow sufficient clearance to drill holes and tighten mounting nuts Note Note Mark the position of the two mounting holes The center of the two holes should be 3 5 89 mm apart Use a 1 4 6 4 mm masonry bit and drill to a depth of at least 1 3 4 with a percussion or hammer drill if possible Clean debris out of the holes Blowing through a straw is an easy way to do this You may want to wrap a little masking tape 1 3 4 up from the point of the drill bit to mar
9. ES U USER GUIDE and that all local electrical safety regulations are observed 11 DocuMENT 301925 REVISION A EMI RFI To prevent EMI RFI susceptibility and interference an overall shield should be provided and cables must be carefully constructed to ensure shields terminate to the connector to provide a full 360 termination This provides a low impedance path for high frequency noise to ground and does not allow high frequency to leak onto unprotected wiring in the cable The instrument s case and cable shields should generally be grounded to a low impedance earth ground The EpiSensor contains circuitry that will prevent damage from ESD transients Use the stainless steel screw on the flange of the instrument as the case ground connection point To be effective this point must be connected to a low impedance earth ground To provide low impedance connection to the ground Attach the EpiSensor grounding screw to the ground with a heavy gauge wire 3 mm in diameter lt 10 AWG or thicker or a tinned copper braid at least 1 2 cm 1 2 in width To be effective this wire or braid should be as short as possible and have no sharp turns The connection to the grounding point should have a large area connection that is tightened and not subject to corrosion Special clamps are available from electrical supply houses to make these connections In a building or structure where close lightning strikes are unlikely a metallic
10. Pole 2 p3 3290 12631 Pole 3 pa 3290 12631 Pole 4 V s is the Laplace transform of the output voltage A s is the Laplace transform of the input acceleration Figure 11 shows the amplitude phase and step response of this pole zero representation Additional references to pole zero responses and damping are available on the Kinemetrics website Application Note 39 gives the response of the FIR filters used in Altus Recorders The FIR filters dominates the overall system response at sample rates of up to 250 samples per second EPISENSOR ES U USER GUIDE EPISENSOR ES U USER GUIDE DOCUMENT 301925 REVISION A Figure 11 Amplitude phase and step response Frequency Response Amplitude 0 50 100 150 200 Frequency Frequency Response Phase 0 50 100 150 200 Frequency Step Response 31 DocuMENT 301925 REVISION A Polarity Conventions 32 Unlike previous generations of Kinemetrics force balance accelerometers the EpiSensor has a positive output for acceleration along the sensitive axis Positive polarity is the international standard in weak motion seismology With Kinemetrics decision to adopt a positive polarity with the EpiSensor FBA it is now the standard in strong motion seismology as well Previous Kinemetrics FBA designs produced a negative output for positive acceleration along each axis EPISENSOR ES U USER GUIDE DOCUMENT 301925 REVISION A 6 Advanced Installations This c
11. cable esta polarizado a tierra en uno de sus lados terminales un voltaje potencialmente letal puede existir entre el otro lado terminal del cable y el polo a tierra Considere este peligro durante la instalaci n y obtenga ayuda de un electricista calificado si este peligro existe NO OPERE EN ATMOSFERAS EXPLOSIVAS El EpiSensor no proporciona ninguna protecci n explosiva para descargas est ticas componentes que generen arcos el ctricos No operar el equipo en una atm sfera de gases explosivos EPISENSOR ES U USER GUIDE SAFETY 7 Symboles amp Terminologie A Ya SAFETY 8 Les symboles suivant peuvent figurer sur les amp quipements Kinemetrics ou dans ce manuel Signifie Attention Quand vous rencontrez ce symbole sur un instrument veuillez vous r f rer la section de ce manuel signal e par la m me marque Avant m me d effectuer la premi re op ration sur l instrument vous devez lire la section correspondante de ce manuel Faite attention si vous voyez cet symbole Indique une mise la terre faible bruit Les objets portant cette marque doivent tre reli s la terre afin d assurer un fonctionnement optimal Elle est aussi utilis e pour les l ments de protection contre les interf rences magn tiques les perturbations hautes fr quences radio et contre les surtensions Cette mise terre n est pas une mise terre de s curit pour une protection contre les choques lectriques Indique une a
12. or East West orientation For a sensor mounted on a horizontal surface which is to sense vertical motion the horizontal case orientation can be whatever is most convenient DOCUMENT 301925 REVISION A 8 Tighten the stud nut with a 7 16 end wrench and check the orientation As you tighten the nuts the studs will move slightly forcing the locking cones to firmly grip the concrete The final torque should be 20 26 inch pounds 2 26 2 94 Nm Note If you use a compass to determine the true north south axis be sure to correct for the difference between magnetic north indicated by the compass and true north magnetic declination This deviation depends on your location find the correct deviation on a local topographical map Connecting to the Data Logger If you have purchased an optional connector and Kinemetrics mating cables just connect the two cables and proceed to the next section If you are m Making your own cable Using a cable that is longer than 1 000 feet 330 meters Using a cable that has conductors thinner than 20 AWG Or using the high gain differential output read Chapter 6 Advanced Installation If you are connecting to the sensor pigtail proceed with the following instructions Pigtail Wiring There are several ways to connect to the unit s pigtail Use a terminal block that clamps directly to the wire such as those made by Phoenix Contact Attach spade terminals to the wiring by cr
13. the location of the EpiSensor Faulty electrical wiring returning large currents to ground normally causes these differences It is the user s responsibility to ensure that hazardous conditions are not created and that all local electrical safety regulations are observed Grounding The cable assembly technique used for connecting the EpiSensor to an Altus instrument is designed to allow future compliance with the ce requirements of the emissions and immunity standards EN 55022 Class A EN 50082 2 of the European Community EPISENSOR ES U USER GUIDE DOCUMENT 301925 REVISION A Use with Non Kinemetrics Data Loggers If you are using the EpiSensor with a non Kinemetrics data logger you must match the power calibration and output of the EpiSensor with that of the recorder Kinemetrics Services Group can provide help with this and can also supply conversion boxes to interface to some commonly used seismic instrumentation Power Supply The standard EpiSensor requires a well regulated low noise 12V 5 or 15V 5 supply that can provide adequate current for the configuration you are using The supply should be low noise less than 50 mV of ripple The single supply option can tolerate a relatively wide input range from 10 to 18 VDC The supply should be low noise and have less than 100 mV of ripple to ensure low noise performance of the sensor Caution Incorrect power to the EpiSensor can cause incorrect readings
14. the red wire in the pigtail m 12V is present on Pin H of the optional connector or the brown wire in the pigtail The power common is connected to Pin J on the optional connector or the single black wire power supply common in the pigtail In the single supply EpiSensor option verify that 12V is present on Pin E on the optional connector or the red wire in the pigtail The power common is connected to Pin J on the optional connector or the single black wire power supply common in the pigtail E Pin His not connected Switch the power source off and connect the cable or connector to the unit Turn the power back on Caution Connecting incorrect voltages or wrong polarities gt 15 75V will seriously damage the EpiSensor Zero Adjusting the EpiSensor After the EpiSensor has been installed and connected to the correct power measure the DC offset It should be as close as possible to zero so that the recorded data has minimal offset With minimal offset the full range of the EpiSensor and recorder can be utilized EPISENSOR ES U USER GUIDE 13 DOCUMENT 301925 REVISION A Methods of Measuring the DC Offset If the EpiSensor is near the recorder you may zero the accelerometer by using the recorder as if it were aDVM If you are using an Altus recorder use the AQ DVM command in QuickTalk s terminal mode If the EpiSensor is located at the end of a long cable build a break out cable to access and m
15. ya sea desde un registrador o desde una fuente de 12 15V provista por el usuario Si usted planea alimentar el EpiSensor desde un registrador conecte el registrador a una fuente de poder cargador suministrado por Kinemetrics como se describe en cada manual del usuario para el registrador Para suministrar energfa directamente al EpiSensor usted necesita una fuente de poder de bajo ruido y regulado 12 15V el cual debe ser apropiadamente conectado a tierra y cumplir con todas las regulaciones locales que apliquen SISTEMA DE PODER CARGA PROVISTO POR EL USUARIO Si usted provee su propio sistema de poder carga usted tiene que estar seguro que el sistema proporciona el voltaje correcto y la corriente requerida por el EpiSensor bajo todo las condiciones de operaci n Usted es responsable por la seguridad de su sistema de carga Si usted deriva energ a de suministro principal usted tiene que asegurarse que ha provisto un polo a tierra adecuado para todo el equipo Si usted suministra sus propias bater as siga las recomendaciones de seguridad del fabricante CABLEADO Y POLO A TIERRA DELSENSOR En algunos casos el EpiSensor estar a una distancia lejos del registrador En estas instalaciones existe la posibilidad de una elevada diferencia de potencial entre dos localidades de polo a tierra debido ya sea a fallas en el alambrado del AC o corrientes de un extremadamente alto retorno de EPISENSOR ES U USER GUIDE tierra Cuando el
16. 00 EZ 20 0000 E 20 0000 Ch 1 0 0505608Vmax 0 0413972Vmid 0 1333553Vnin 0 1839 161Vpp The height of the pulse will depend on the full scale setting of the instrument but will correspond to a g level of approximately 0 125g The exact value will be 2 5V multiplied by the sensor module s calibration coil sensitivity value which is provided on the sensor s data sheet EPISENSOR ES U USER GUIDE DOCUMENT 301925 REVISION A Altus software released prior to August 1998 supports functional tests on the earlier generation of Kinemetrics force balance accelerometers but does not support the EpiSensor If you perform a functional test or sensor response test on an EpiSensor using oler software the record will appear as in the screen below Figure 5 Functional test using software released prior to August 1998 The record looks like this because the calibration coil enable is only enabled during the undamped portion of the old FBA 11 style functional test Sensor Response Test The sensor response test for the EpiSensor using Altus software released after August 1 1998 measures the response of the sensor to white noise input The digitakto analog converter in the recorder drives the calibration coil with an analog voltage corresponding to a pseudo random number sequence The resulting file contains the information needed to compute the sensor response For additional information on the sens
17. 700277 cable Note If using non Kinemetrics cable the signal should be sent in a shielded twisted pair with five additional signal wires for the power and calibration control Heat shrink tubing 1 4 diameter cable tie wraps and electrical tape Mating connector for units with optional connector Terminal strip butt splices or wire nuts for joining pigtail to main cable Two mounting anchors provided FerriShield optional Equipment Battery powered digital volt meter DVM Compass for checking sensor orientation Camera to photograph the completed installations for the commissioning report recommended EPISENSOR ES U USER GUIDE DocuMENT 301925 REVISION A Mounting amp Orienting EPISENSOR ES U USER GUIDE Determine the location and orientation of the EpiSensor and which flange to use for mounting The arrow on the EpiSensor case indicates the sensitive axis of the accelerometer Anchor the sensor to a concrete floor or slab or a secure structural element such as a steel beam in a building as described below An intermediate plate often provides an easier way of mounting to a structural concrete or steel beam Note To accurately record strong ground motions of gt 0 1g it is essential that the EpiSensor is anchored to the structure or slab This is contrary to weak motion installations where sensors are just placed on the ground and leveled In weak motion the weight of the instrument and friction between
18. NT 301925 REVISION A Note on Full Scale Range EPISENSOR ES U USER GUIDE All full scale ranges are stated as the voltage you would measure with a voltmeter between the and outputs for the sensor when full scale acceleration is applied to the unit For example with a differential output of 20V on a range of 1g you would measure 20V if you applied 1g to the sensor In this case the positive output would be at approximately 10V with respect to ground while the negative output would be at approximately 10V with respect to ground If you applied 1g you would measure 20V between the outputs 15 DOCUMENT 301925 REVISION A 3 Operating Basics The EpiSensor is designed as a very flexible low noise accelerometer and can be configured to satisfy a wide variety of acceleration sensing requirements Configurable options include Full scale acceleration sensitivity of sensor 1 4 1 2 1 2 and 4g Single ended or differential output Output voltage can be 2 5V or 10V single ended Output voltage can be 5V or 20V differential This chapter discusses EpiSensor operation m Polarity conventions How to configure operating modes Use of the calibration coil which allows verification of the sensor s transfer function Power supply options The photo shows the EpiSensor in its anodized aluminum housing which also includes A sealed cover to prevent moisture and dirt from entering th
19. Nm 6 Re inspect the gasket EPISENSOR ES U USER GUIDE DOCUMENT 301925 REVISION A 4 Maintenance Recommended Maintenance The EpiSensor is designed for many years of unattended use but we recommend that you perform the following checks a minimum of once a year If the EpiSensor is connected to an Altus recorder equipped with a modem this maintenance check can be performed remotely and more frequently See the Altus recorder manual for more details Adjust the Accelerometer If the offset of the EpiSensor module measures more than the suggested limit shown in Table 1 it should be adjusted Refer to Chapter 2 for instructions on adjusting the zero offset Complete a Functional Test Kinemetrics recommends that you perform a functional test on the accelerometer at each service visit to check that the unit is operational and as a baseline record for future visits Refer to Chapter 3 for instructions on performing the functional test If the unit is connected to a Kinemetrics recorder refer to the recorder s manual for instructions on performing the functional test Refer to Chapter 6 if the unit is connected to a non Kinemetrics data acquisition system Calibration The EpiSensor is very stable and maintains its calibration in the field for many years A functional test will provide a good indication of whether the sensor is working properly A further quick check of the calibration can be performed by simply tilting the se
20. RBE ablesen N ES A Ta 34 User Suppliicd Cable eye rennen Near 36 Ground Dear cae cotton Sue dll ea 36 Use with Non Kinemetrics Data Loggers 37 Power Supply unica id nunun arn Rhein 37 Figures Tables DocuMENT 301925 REVISION A Output Vollase site ida 37 Calibration Sequence acrilico atitaa 38 Ground Loop Prevention senusasiinenlitksink ps 39 EpiSensor ES U Specifications cic re kA RR a RE Re 40 Figure ls EpiSensor ES Usage en 2 Figure 2 EpiSensor mounting dimensions 6 Figure 3 Drilling EpiSensor mounting holes u 222002202 2er snnennnennnnennn 7 Figure 4 Display of functional ted 18 Figure 5 Functional test using software released prior to August 1998 19 Figure 6 Jumper settings for sensor g level 21 Figure 7 Jumper settings for sensor output voltage eee eee eeeeeeeeeeeeee 22 Figure 8 Jumper settings for single ended or differential output 22 Figure 9 Jumper settings for 2g 2 5V single ended configuration 23 Figure 10 Simplified block diagram of an accelerometer 21 Figure 11 Amplitude phase and step response 31 Table Ve BS US ening ass u ea 9 Table 2 EpiSensor Outputs to Altus instrument channels 10 Table 3 EpiSensor Connections to Altus external sensor connector
21. User Guide EpiSensor Force Balance Accelerometer Model FBA ES U Document 301925 Revision A April 2002 Trademarks This manual copyright Kinemetrics Inc 2002 All rights reserved Kinemetrics products are covered by U S and foreign patents issued and pending Printed in U S A The trademarks used throughout this manual registered or not are QuickTalk M QuickLook K2 Mt Whitney Etna EpiSensorM HypoSensor FerriShield and Microsoft Windows Kinemetrics Inc 222 Vista Avenue Pasadena CA 91107 USA Phone 626 795 2220 M Fax 626 795 0868 E mail support kmi com services kmi com Website www kinemetrics com Kinemetrics SA Le Tresi 3 1028 Preverenges Switzerland Phone 21 803 2829 M Fax 21 803 2895 E mail kmi_sa bluewin ch DocuMENT 301925 REVISION A Table of Contents Safety 1 Introduction The EpiSensor ES U una aa 1 Inspecting the E pl Sens Ores x cc ae ne tn dt nt 2 2 Installation Basics Requirements Tor Installation aaa 3 Required Tools iii iden idad danos Rh 3 Reg ired PP Aa 4 Required Equipment e ee 4 Mounting amp Onenn AAA ete eee eee tant 5 Connecting to the Data Logger a sein 8 Pigtail Wiringu furent td ia 8 Grounding the EIA re 11 Salely A Eins 11 EMU RET ee nenne 12 Low Noise Operation ovario einen 12 Powering th PERIS Cas a tn nie hs nn AN eee 13 Zero Adjusting the Episensora ana 13 Methods of Measuring the DC Offset
22. ations SENSOR GROUNDING AND CABLING In some cases the EpiSensor will be a long distance from the recorder In these installations it is possible due either to faulty AC wiring or extremely high earth return currents for a high potential difference to exist between the grounds at the two locations When the cable is grounded at one end a potentially lethal voltage can exist between the other end of the cable and ground Consider this danger during installation and get help from a qualified electrician if this danger exists Do NOT OPERATE IN EXPLOSIVE ATMOSPHERE The EpiSensor provides no explosive protection from static discharges or arcing components Do not operate the equipment in an atmosphere where explosive gases are present EPISENSOR ES U USER GUIDE Sicherheit Symbole amp Begriffe Diese Symbole k nnen auf Kinemetrics Ger te oder in diesen Manuel erscheinen Bedeutet Achtung Wenn sie dieses Symbol auf ein Ger t sehen muss den gleich markierten Teil dieses Manuels beachet werden Bevor irgend eine Unterhaltsarbeit angefangen wird muss dieser Teil des Manuels gelesen werden Wenn Sie dieses Symbol sehen bitte besondere Achtung geben Bedeutet Erdung Das erwaente Teil sollte geerdet werden um eine low noise operation zu versichern und dann auch als Erdung f r EMV FRI und Transienten und solch eine Erdung wird nicht als Sicherheit gegen elektrischen Schock dienen Bedeutet Wechselstromzufuhr AC mit Elektro
23. demas sirve como un retorno a tierra para el EMI RFI y transitorios Tal polo a tierra no trabaja como un polo a tierra de seguridad para protecci n contra choques el ctricos Significa una linea de energia de Corriente Alterna AC Significa una linea de energ a de Corriente Directa derivada de una l nea de energ a AC Significa una Unidad Sensitiva a Electrost tica Electrostatic Sensitive Device ESD indicando que usted debe tener cuidado y observar todas las precauciones para el manejo de tales unidades Estos t rminos aparecer n en este manual Note sentencias identificando informaci n que Usted debe considerar cuidadosamente antes de dirigirse a la siguiente instrucci n u Opci n SAFETY 5 Caution sentencias identificando condiciones o practicas que podrian resultar en da o del equipo el software u otra propiedad WARNING sentencias identificando condiciones o practicas que podrian resultar en una lesi n personal o la perdida de la vida Los ltimos dos t rminos mencionados arriba podrian tambi n aparecer en el equipo Kinemetrics que Usted ha comprado pero no necesariamente indiferentemente Usted debe definitivamente tomar notas serias de las precauciones y advertencias en este manual Precauciones Especificas SAFETY 6 Siga las precauciones a continuaci n para garantizar su seguridad personal y prevenir dafios al EpiSensor FUENTE DEL PODER El EpiSensor debe ser alimentado con energia
24. e cot du cable et la terre Considerez ce danger pendant l installation et demandez l aide d un electricien si ce danger existe NE PAS UTILISER EN ATMOSPH RE EXPLOSIF Le EpiSensor ne comprend pas de protection contre les explosions dues aux d charges statiques ou aux composants pouvant provoquer des arcs Ne pas utiliser ces composants en pr sence de gaz explosifs SAFETY 10 EPISENSOR ES U USER GUIDE DOCUMENT 301925 REVISION A 1 Introduction This document is the User s Guide to EpiSensor Model FBA ES U a single axis acceleration sensor Kinemetrics also produces a triaxial EpiSensor FBA the FBA ES T and the FBA ES SB shallow and FBA ES DH HypoSensor triaxialborehole packages Kinemetrics strong motion accelerographs feature a triaxial EpiSensor Altus deck This manual applies only to EpiSensor Model FBA ES U For the sake of brevity the instrument is referred to simply as the EpiSensor Kinemetrics is committed to ensuring a successful installation For assistance with planning installation operation or maintenance contact Kinemetrics at the locations listed in the front of this manual Kinemetrics also has an extensive Services Group that can install maintain and analyze the data from your EpiSensor This chapter provides an overview of the EpiSensor and inspection instructions The EpiSensor ES U EPISENSOR ES U USER GUIDE The EpiSensor is a uniaxial accelerometer optimized for earthquake reco
25. e instrument One access hole covered by seal screws through which zero offset may be adjusted A cable visible at lower right outside the housing for the analog output voltages from the accelerometers and for supplying power and control signals to the EpiSensor EPISENSOR ES U USER GUIDE 17 DocuMENT 301925 REVISION A Signal Polarity Unlike previous generations of Kinemetrics force balance accelerometers the EpiSensor generates a positive output for acceleration in the direction of the orientation axis arrow on the housing For information on polarity conventions see Chapter 5 Reference Required Power If you are using the EpiSensor with a Kinemetrics Altus instrument the 12V power will be supplied from the recorder If you are using another recording system you will need to supply the correct power Refer to Chapter 6 Advanced Installation Topics for more information Performing a Functional Test with an Altus Recorder 18 Altus instrument firmware released after August 1 1998 performs a dual polarity pulse test on EpiSensors as the standard functional test when correctly configured This firmware is available at the Kinemetrics website Figure 4 Display of functional test 17 Kinemetrics QLWIN Version 2 40d 4 18 97 _lalIx File ZoomSize Pan Chan Screen Header Help C KMI DOCS APPNOTES LOOOL EYT FT 7 31 1998 212 10 07 10 000 Display 6 3 AO Rl D1 YO 1 Cond 6 13 1 ZCond 5 95 1 BZ 0 00
26. easure voltages in each of the wires in the EpiSensor cable Be sure to supply the EpiSensor with 12 VDC or 12 VDC for the single power supply option Performing the Zero Adjustment Refer to Figure 1 to see the access screw that when removed provides access to the zero adjustment screw on the sensor module Naturally it is impossible to achieve zero offset The table below will tell you the acceptable range for DC offset for each possible ES U configuration If desired smaller offsets may be achieved with some patience 1 Remove the zero balance access screw on the top of the EpiSensor case 2 Gently insert a hex ball 5 64 or 2 mm wrench perpendicular to the case as far as it will go into the adjustment hole and make very minimal adjustments counterclockwise for negative adjustments and clockwise for positive 3 When the offset is in an acceptable range based on Table 2 carefully remove the hex wrench and replace the access hole screw Important Give the unit a moderate tap with a screwdriver handle The adjustment screw can have a residual stress that may cause and offset in data during a large earthquake Tapping eliminates the residual stress Note One turn changes the output by about 1g Table 4 Reasonable zero offset voltages F Single ended Differential Single ended Differential ull scale range 2 5V output 5V output 10Voutput 20V output 10m som nv EPISENSOR ES U USER GUIDE DOCUME
27. emodulated and filtered creating a DC error term in the feedback amp lifier The feedback loop compensates for this error signal by passing current through the coil to create a magnetic restoring force to balance the capacitor plates back to their original null position The current traveling through the coil is thus directly proportional to the applied acceleration By passing this current through a complex impedance consisting of a resistor and capacitor it can be converted to a voltage output proportional to acceleration with a bandwidth of approximately 200 Hz Selecting a particular resistor value sets the ful scale range The resistor values are determined by a high accuracy network so the range can be set at 0 25g 0 5g 1g 2g and 4g without re calibrating the sensor span The capacitor and overall loop gain are selected along with the resistor to ensure an identical transfer function on each range This is why two sets of jumpers must be changed together to modify the range The voltage output of the resistor capacitor network is set at 2 5V for the acceleration value corresponding to the particular range For example with the 2g range a 1g acceleration would cause a 1 25V output on the 4g range 1g would result in a 0 625V output EPISENSOR ES U USER GUIDE DocuMENT 301925 REVISION A This voltage is then passed into the amplifier The amplifier amplifies this signal by either 1 or 4 selected by jumpers to g
28. erating temperature 20 to 70 C 0 to 160 F 40 EPISENSOR ES U USER GUIDE
29. hapter contains information on various advanced installation topics that may apply to your system Kinemetrics Service Group can provide additional information on these topics CE Compliant Installations The EpiSensor has not yet been CE certified Using EpiSensors with Altus Instruments This section discusses the use of the EpiSensor with Kinemetrics Altus Instruments The K2 amp Mt Whitney The 4 Channel ADC DSP board in a 4 Channel K2 can supply sufficient power for three ES Us The ES U s should normally be configured as 2 5V single ended output units The 6 channel ADC DSP boards used in the K2 and Mt Whitney can supply 125 mA from the 12 and 12V power lines for the sensors and any gain boards Gain boards draw approximately 5 mA from both power lines and would normally not be used with an EpiSensor The board supplies sufficient current for three ES U units in any configuration even with gain boards The board will also supply sufficient current for six ES U s in the 2 5V single ended output configuration EPISENSOR ES U USER GUIDE 33 Long Cables 34 DOCUMENT 301925 REVISION A If you wish to use six ES U units with a high gain output or a combination of ES U s and other sensors you need to work out the current requirement as shown in Table 8 The total current for all sensors and gain boards must not exceed the 125mA limit If the configuration would exceed this limit we suggest using one of the f
30. igure 8 shows the jumper settings for either single ended or differential output configurations Figure 8 Jumper settings for single ended or differential output Smgle Ended Differential 22 EPISENSOR ES U USER GUIDE DOCUMENT 301925 REVISION A Figure 9 shows a sample of the most common setting appropriate for many strong motion applications when the EpiSensor is used with an Altus recorder Figure 9 Jumper settings for 2g 2 5V single ended configuration Note that while the above settings are independent each of the options must be configured correctly for the EpiSensor to function properly Power Supply Options The EpiSensor is offered in two power supply configurations Dualsupply standard m Single supply optional The jumpers for these options are set at the factory and should not be changed Caution Damage to instrument When the EpiSensor is configured for single supply operation do not connect any power source to the brown wire or Pin H on the connector Calibration Coil The EpiSensor is equipped with a calibration coil This coil is isolated from other EpiSensor circuitry and accurately emulates the effect of acceleration on the system This coil can be used to verify both the static acceleration sensitivity of the EpiSensor and the dynamic response of the system When used with Altus recorders the calibration signals are automatically applied EPISENSOR ES U USER GUIDE 23 24
31. imping or soldering and then use a screw terminal block for the connections Use small wire nuts for temporary installations These connections must always be protected from moisture and physical damage To prevent EMI RFI from interfering with your installation it may be necessary to make these connections in a grounded metal box Make the connections using the wiring table below Caution Incorrectly wiring these connections can result in serious damage to the EpiSensor or the attached recorder 8 EPISENSOR ES U USER GUIDE EPISENSOR ES U USER GUIDE DOCUMENT 301925 REVISION A Table 1 ES U wiring tional Pigtail Wire Color Span Connector Function KMI 851699 Black wire in twisted pair wire in twisted Black wire in twisted pair signal Twisted pair shield Signal shield CET a CS Outer shield Cal coil enable Power supply common Outer shield In order to avoid confusion please note that the pigtail contains A twisted pair consisting of a black wire a white wire and a shield inside a white insulation jacket A single black wire A single white wire TWISTED PAIR TO INPUT CHANNEL 1 Connect the black wire in the twisted pair to the positive input channel of the recorder Connect the white wire in the twisted pair to the negative input channel of the recorder Connect the shield wire in the twisted pair to the recorder s ground for the channel to which the EpiSensor is connected
32. instruments If the EpiSensor is used with an Altus recorder this distance can be extended up to 2 000 feet For cable runs of this length we recommend installation in a grounded metal conduit If the cable is not installed in its own conduit and maximum resolution is required it should not be run alongside cables carrying heavy AC or transient currents EPISENSOR ES U USER GUIDE EPISENSOR ES U USER GUIDE DOCUMENT 301925 REVISION A Cable lengths must be reduced considerably for the high gain differential option The EpiSensor requires a minimum operating voltage of 11 5V to be sure it can supply the 10V output with respect to ground In the worst case the standard Altus unit s power output is only 11 6V Note that this configuration will seldom be used with K2s Mt Whitneys and Etnas because the output does not match the 2 5V input of the recorder It will be used with the Makalu but in this case the worst case power output from the Makalu is 13 5V giving a much greater allowed voltage drop of 2V Calculations for the 2g operating range are provided in the following tables These figures are a conservative limit for all ranges except 4g The 4g units require an additional 5mA of dynamic current Table 6 Typical Cable Resistance Calculation EpiSensor low power S T ua Sensor minimum operating voltage 10 0 V Maximum supply current Minimum supply voltage 11 6 V Allowed cable voltage drop One way allowed cable dr
33. ion types and site conditions because grounding has five goals some of which can be mutually exclusive These goals are Prevent life threatening voltages in or on the equipment Immunity from EMI RFI interference susceptibility Prevent radiation of EMI RFI from the equipment interference Prevent damage to the equipment from lightning ESD etc Low noise operation Safety First Obviously the most important goal of any grounding scheme is to ensure the safety of people Design and evaluate your grounding system with this in mind Since the EpiSensor contains no high voltage circuitry and is not connected to AC power safety concerns arise from the recorder end of the connection cable When using your own power system be sure that AC power is fully isolated from the DC power supplied to the EpiSensor and that the power supply is safely grounded In its normal configuration the EpiSensor is isolated from its case except for a high frequency EMI RFI filter WARNING Potential lethal voltages Potentially lethal voltages can exist between the conductors on the cable or internal components and the exposed metal case of the EpiSensor These occur due to differences in ground potential between the location of the recorder and the location of the EpiSensor or faults in the recorder or user supplied power supply It is the user s responsibility to ensure that hazardous conditions are not created EPISENSOR
34. ists we recommend you return the unit to Kinemetrics for repair and re calibration EPISENSOR ES U USER GUIDE DOCUMENT 301925 REVISION A 5 Reference Theory of Operation The EpiSensor consists of a force balance accelerometer FBA inside a housing The accelerometer module plugs into a board that provides the final output circuit and the carrier oscillator The figure below shows a simplified block diagram of the major components of an FBA Figure 10 Simplified block diagram of an accelerometer Functional Test Pulse Normally Open EPISENSOR ES U USER GUIDE 27 28 DOCUMENT 301925 REVISION A Working Principle The oscillator applies an AC signal of opposite polarity to the two moving capacitor plates also referred to as the moving mass When the accelerometer is zeroed and when no acceleration is applied these plates are symmetrical to the fixed central plate and no voltage is generated Acceleration causes the coil and capacitive sensor plates which are a single assembly mounted on mechanical flexures springs to move with respect to the fixed central plate of the capacitive transducer This displacement results in a signal on the center plate of the capacitor becoming unbalanced resulting in an AC signal of the same frequency as the oscillator being passed to the amplifier The amplifier amplifies this AC signal This error signal is then passed to the demodulator where it is synchronously d
35. ithin the voltage limits and the bandwidth of the sensor Thus the calibration sequence can range from the simple pulses described below to single frequency sine waves or chirped sine signals Be certain that the Cal line is not active when the EpiSensor is not powered this could damage the unit If the data logger cannot perform a functional test a simple test box can be built to simulate the desired calibration sequence A suggested sequence is as follows 1 Apply OV to the Cal line 2 Turn CCE to 12V EPISENSOR ES U USER GUIDE DOCUMENT 301925 REVISION A 3 Wait 2 seconds 4 Apply 2 5V to Cal for 2 seconds 5 Change Cal to 2 5V for 2 seconds 6 Change Cal to OV for 2 seconds 7 Turn CCE off by connecting it to OV This will produce a positive pulse followed by a negative pulse Caution The CCE line must not be enabled during normal operation severely degraded noise performance can result Applying voltage to the Cal line or the CCE line when the unit is not powered will result in damage Applying voltage above the power supply lines to the Cal line or the CCE line will also damage the unit Ground Loop Prevention When the EpiSensor is used with non Kinemetrics digitizers it is essential that the ground connections be carefully planned in order to prevent ground loops Please see the section in this chapter on grounding This is especially important when using a PC based data acquisition system We recom
36. ive a single ended output of either 2 5V or 10V A precision resistor network also determines this gain value A second amplifier is also present which inverts the signal from the first and can be connected to the negative output lead via jumpers This allows the unit to give a differential 5V or 20V to match the input to 24 bit digitizers Features Each EpiSensor module is equipped with a calibration coil Applying a current to this coil simulates the effect of an acceleration applied to the sensor This provides a much more thorough check of the sensor s performance than older techniques that merely stimulate the feedback circuitry The calibration coil is open circuit in normal use to prevent noise pick up To utilize the calibration coil remotely from outside the unit the calibration coil enable signal must be activated by applying a DC voltage of 5V to 12V with respect to ground A voltage signal applied to the calibration line with CCE active will cause the EpiSensor module to respond with an acceleration output of approximately 0 05 g per volt applied The exact calibration coil sensitivity is provided on the data sheet of each module m All external connections are passed through transient protection These elements protect the sensor from the effects of electrostatic discharge ESD Each line is also filtered to prevent the entry of electromagnetic interference or radio frequency interference EMI RFI to the se
37. k how deeply to drill The depth of the hole can be checked with a nail or narrow screwdriver The hole should be vertical do not drill at an angle Screw the nut washers onto each stud until the top of the nut is flush with the top of the stud This will make is easier to insert the studs and prevent damage to the threads It is very important not to damage the threads of the anchor stud Place a small piece of wood or similar object on top of the nut before tapping with the hammer This will dissipate the energy between the stud nut and the hammerhead and avoid damage to the threads EPISENSOR ES U USER GUIDE EPISENSOR ES U USER GUIDE DOCUMENT 301925 REVISION A Figure 3 Drilling EpiSensor mounting holes Percussion or hammer drill Drill bit with diameter to fit anchor stud Drill slightly deeper than length of anchor stud gt 2 Hammer Nut aligned with top of anchor bolt Gently tap the top of each of the anchor studs with a hammer The studs are now in position but not firmly seated Carefully remove the nuts Place the EpiSensor mounting flange over the bolts and check that the orientation arrow is pointing in the correct direction Place the washers and nuts on each of the studs and hand tighten Align the side of the EpiSensor case that is parallel to the orientation arrow carefully in the desired direction This would normally correspond with a major axis of the structure or to the North South
38. ld result in damage to the equipment the software or other property WARNING statements identify conditions or practices that could result in personal injury or loss of life EPISENSOR ES U USER GUIDE SAFETY 1 Specific Precautions SAFETY 2 Follow the precautions below to ensure your personal safety and prevent damage to the EpiSensor POWER SOURCE The EpiSensor must be supplied with power either from a recorder or from a customer supplied 12V or 15V power supply or a 12V supply for the single supply option If you plan to power the EpiSensor from a recorder connect the recorder to a power supply charger supplied by Kinemetrics as described in each recorder s user manual To supply power directly to the EpiSensor you need a low noise regulated 12V or 15V power supply or a 12V supply for the single supply option that is safely grounded and meets all applicable local regulations The EpiSensor will be damaged if the power is connected with the wrong polarity USER SUPPLIED POWER CHARGING SYSTEM If you supply your own power charging system be sure that the system provides the correct voltage and current required by the EpiSensor under all operating conditions You are responsible for the safety of your charging system If you get power from the mains supply be sure you have supplied adequate grounding for all the equipment If you supply your own batteries follow the manufacturer s safety recommend
39. limentation en courant alternatif AC Indique une Alimentation en courant continu DC d riv e d une alimentation alternative Indique la pr sence d un composant sensible aux d charges lectrostatiques ESD Cela signifie qu il faut observer toutes les pr cautions d usage en manipulant ce composant Les termes suivant apparaissent dans ce manuel Note Indique la pr sence d une information que vous devez particuli rement consid rer avant de passer la prochaine instruction or operation EPISENSOR ES U USER GUIDE Caution Indique une condition ou op ration qui peut entra ner des dommages votre quipement au logiciel ou d autres propri t s WARNING Indique une condition ou op ration qui peut entra ner des blessures corporelles ou la perte de la vie Les deux derniers termes mentionn s peuvent appara tre sur les quipements de Kinemetrics que vous avez acquis mais pas n cessairement indiff remment 1l est conseill de prendre au s rieux les avertissements de ce manuel Pr cautions Sp cifiques JAN EPISENSOR ES U USER GUIDE Observez toutes les pr cautions suivantes afin d assurer votre s curit personnelle et d viter des d g ts aux composants de votre capteur EpiSensor ALIMENTATION Le EpiSensor doit tre aliment avec un courant de 12 15 VDC fourni par l enregistreur ou par votre propre syst me d alimentation Si vous alimentez le EpiSensor avec l
40. mend using the differential output of the EpiSensor to prevent common mode problems When using single ended output the signal return should be connected to the negative input of the analog front end s differential or instrumentation amplifier and not to circuit common The common connection should return to the power supply through only one path When using a separate mains power supply for the EpiSensor be very careful that it does not provide a separate ground return through the AC mains ground to the data acquisition computer Use a star ground configuration for your system with the EpiSensor power supply data acquisition system and PC all grounded at the same point In our experience most noise problems with any installation are normally a result of power grounding or cable shielding EPISENSOR ES U USER GUIDE 39 DocuMENT 301925 REVISION A EpiSensor ES U Specifications Triaxial force balance accelerometer Bandwidth DC to 200 Hz Full scale range User selectable at 0 25g 0 5g lg 2 or 4g Output User selectable at 2 5V and 10V single ended 5V 20V differential Access hole for simple efficient adjustment Dual bolt for horizontal or vertical mounting 2 0 Cross axis sensitivity lt 1 including misalignment Zero point thermal drift lt 500ug C Quiescent current lt 12 mA from 12V Connection 1 0m pigtail with stripped and tinned ends for splicing or junction box termination Op
41. nsor m Optionally the unit can be equipped with a 12V to 12V converter module allowing the EpiSensor to be powered from a single 12 15V supply Pole Zero Representation of the EpiSensor EpiSensor accelerometers are closed loop force feedback sensors measuring the relative displacement of a moving mass plates with respect to the sensor case The sensor s transfer function TF depends almost entirely on the electronic components rather than on the mechanical EPISENSOR ES U USER GUIDE 29 DocuMENT 301925 REVISION A components of the sensors The influence on the transfer function of the mechanical damping spring elements and internal RC low pass filter in the trans conductance amplifier stage within the closed loop path of the sensor are negligible for most applications We have determined a good empirical model of the system which uses two pairs of conjugate poles to represent the transfer function of the instrument If this transfer function is corrected for the DC sensitivity of the sensor the amplitude agreement is within 0 5 dB over the bandwidth of the sensor The phase agreement is within 2 5 in the 0 100 Hz band and within 5 over the full bandwidth of the instrument This model can be represented as Vis 2 kl k2 A s pis p s P3 S Pa where kl 2 46x 10 k2 Sensitivity of sensor in V g from Table 3 1 s is the Laplace transform variable p 981 10091 Pole 1 p2 981 10091
42. nsor 90 and 90 in each axis By tilting the sensor an acceleration of 1g can be measured EPISENSOR ES U USER GUIDE 25 26 DOCUMENT 301925 REVISION A Kinemetrics can supply a tilt table and training in order to perform more accurate calibrations verifications in the field Kinemetrics can also provide on site or factory calibrations traceable to national standards Desiccant Replacement The EpiSensor contains a small package of desiccant that is designed to maintain a low humidity level inside the unit If the case is left open for a long time opened repeatedly for inspection or adjustment or in very humid conditions the desiccant may be incapable of absorbing more moisture This is indicated by the ink on the desiccant pack turning from its original blue to pink When this happens it should be replaced New desiccant can be ordered from Kinemetrics as P N 700403 Be sure to follow electrostatic discharge ESD precautions when them sensor case is opened Instructions for opening and closing the EpiSensor case are provided in Chapter 3 Caution Potential electrostatic discharge ESD hazard to equipment Wear a grounded wrist strap with impedance of approximately 1 M Q when handling the EpiSensor circuit boards to protect components from damage Troubleshooting and Repair If your EpiSensor does not appear to be working we suggest you first check that the cabling and power supply are correct If the problem pers
43. ollowing solutions Contact Kinemetrics about modifying the ADC DSP board to supply more power m Use the single supply option on the EpiSensors powering the units from the 12V battery power on the K2 or Mt Whitney Build your own power supply unit The Etna The Etna can supply power for two ES Us configured as 2 5V single ended output units When using three ES U units the EpiSensor will need either a separate power supply or should use its single supply option and take power from the Etna s 12V This is because the Etna can supply only 40mA on each 12 and 12V power line The only reason to use the differential output with the Etna is to take advantage of its superior common mode rejection in a high noise environment and in this case the unit can only power a single ES U directly For two or three units either a separate power supply or the single supply option powered from the Etna s 12V should be used Makalu The 3 Channel Makalu formerly known as the Everest recorder can power three ES Us connected in any configuration and the 6 Channel Makalu recorder can power six ES Us in any configuration When connecting to the Makalu the units should be configured with the 20V differential input to maximize system noise performance In its lowest power configuration 2 5V single ended output the EpiSensor can be used with the normal Kinemetrics cable P N 700277 for distances up to 1 000 feet with a variety of
44. op One way allowed resistance at full scale output V IR 47 Q Table 7 Typical Cable Length Calculation Cable Resistance per Low power 2g 2 5V Single ended 1000 Feet Maximum Cable Run in Feet 20 10 90 Q 4300 feet 35 36 DocuMENT 301925 REVISION A User Supplied Cable If you are using your own cable be sure that is has sufficient conductors of the required wire gauge for the installation and that it provides adequate shielding to maintain the noise performance of the EpiSensor The conductors used for the signals and the control signals Cal and CCE carry little current The previous section showed examples of the resistance and calculated voltage drop for a cable when using an Altus recorder You can substitute your own values to calculate the allowed cable length for different configurations and cable wire gauges To calculate the maximum current for different EpiSensor configurations use Table 8 To exceed these lengths use a power supply that supplies more than 11 6V but less than 15V Calculate the voltage drop in the cable at the maximum supply current and make sure that it meets the minimum operating voltage for the chosen configuration WARNING Potential lethal voltages With long cables potentially lethal voltages can exist between the conductors on the cable or the exposed metal parts of the EpiSensor These occur due to differences in ground potential between the location of the recorder and
45. or response test consult the Kinemetrics website EpiSensor Configuration EPISENSOR ES U USER GUIDE This section describes how to configure the EpiSensor by placing 2 pin jumpers on specific headers on the oscillator board located directly beneath the lid These jumpers are normally configured by Kinemetrics at the time of manufacture If your EpiSensor is set to the correct range the following instructions for re configuring are unnecessary However if you wish to change the settings it is possible to do so ina laboratory environment 19 DOCUMENT 301925 REVISION A Kinemetrics recommends that you do not attempt to change these jumpers in the field where debris or water could get into the unit To access these jumpers and the headers to which they connect the EpiSensor lid must be removed Opening the EpiSensor Case Caution Potential electrostatic discharge ESD hazard to equipment Wear a grounded wrist strap with impedance of approximately 1 M Q when handling the EpiSensor circuit boards to protect components from damage 1 Remove the four screws on top of the case 2 Gently lift the lid off the EpiSensor 3 Set the screws and the RFI gasket aside in a safe place J umper Selectable Options The features that are controlled by the jumpers on the top board are Full scale range Output voltage level of 2 5V or 10V Differential or single ended output The jumpers can be installed or removed
46. rding applications Inside the waterproof anodized aluminum housing is one EpiSensor force balance accelerometer module The EpiSensor has user selectable full scale recording ranges of 4g 2g 1g 1 2g or 1 4g Its bandwidth of DC to 200 Hz is a significant improvement over earlier generations of sensors The output voltage levels are user selectable at either 2 5V or 10V single ended or 5V or 20V differential The EpiSensor is normally powered with a 12V or 15V external DC power source It is optionally available with a single 12V supply option Full specifications for the unit can be found in Chapter 6 DOCUMENT 301925 REVISION A Inspecting the EpiSensor Carefully remove the EpiSensor from its shipping container Note If you expect to ship the EpiSensor again save the shipping container and packing material Although Kinemetrics takes every precaution in packing its systems shipping damage can still occur If you find a problem note the condition of the shipping container Then contact the freight forwarder and Kinemetrics as soon as possible Please contact Kinemetrics before returning a damaged unit Caution Damage to sensors Dropping the EpiSensor onto a hard surface can damage the sensors Figure 1 EpiSensor ES U Ore of four screws Examine the EpiSensor The case should appear securely sealed showing no sign of dents or scratches EPISENSOR ES U USER GUIDE DOCUMENT 301925 REVISION A 2 Ins
47. rnt Sein wo es dann m glich sein k nnte dass durch besch digte AC Wiring oder Hohe Erdbewegungen ein Spannungsunterschied besteht Es ist daher unbedingt notwendig dass alle angeschlossenen Instrumente am gleichen Spannungspotential geerdet sind Bitte folgen Sie den vom Hersteller gegebenen Empfehlungen VERKABLUNG UND ERDUNG VOM SENSOR Wenn das Kabel an einem End geerdet ist kann ein verh ltnism ssig grosser Unterschied in der Voltage bestehen welcher sehr gef hrlich ist Bitte beachten Sie Diese Gefahr und wenn n tig ziehen Sie das Gutachten eines qualifizierten Elektrikers Ein NICHT IN EXPLOSIONSGEF HRDETE UMGEBUNG GEBRAUCHEN Der EpiSensor hat keinen Explosions schutz von statischen Entladungen oder funkgef hrdeten Bauteilen Benutzen sie die Ger te nicht in Umgebungen mit explosiven Gasen SAFETY 4 EPISENSOR ES U USER GUIDE Seguridad Simbolos amp Terminos Ir gt EPISENSOR ES U USER GUIDE Estos simbolos podrian aparecer en los equipos Kinemetrics o en este manual Significa poner atencion Cuando Usted vea este simbolo en el instrumento referirse a las partes de este manual marcadas similarmente Antes de intentar cualquier servicio en este instrumento Usted tiene que leer las partes relevantes de este manual Si Usted ve este simbolo ponga atenci n cuidadosamente Significa un polo a tierra de bajo ruido El item referido debe estar polarizado a tierra para asegurar la operaci n a bajo ruido y a
48. schock Gefahr Bedeutet Gleichstromzufuhr von AC Versorgung herkommend Bedeutet Elektrostatisch Sensibeles Element ESD f r dessen Handhabung alle vorbeugende Vorsichtsmassnahmen genommen werden m ssen Folgende Darstellungen werden in diesen Manuel erscheinen Note Darstellung welche Informationen Sie erhalten die besonders beachtet werden m ssen bevor sie zum n chsten Schritt gehen EPISENSOR ES U USER GUIDE SAFETY 3 Caution Darstellung bei dem die Missachtung in der Regel Gefahr f r Defekte und St rungen im Ger t Programm oder Zubeh r besteht WARNING Darstellung bei dem die Missachtung in der Regel Verletzungs oder Lebensgefahr besteht Spezielle vorbeugende Massnahmen Alle vorbeugende Massnahmen m ssen beachtet werden F r Ihre pers nliche Sicherheit und um Sch den im EpiSensor zu vermeiden STROMVERSORGUNG Die EpiSensor muss entweder mit Strom von einem Accelerograph oder Ihrer eigenen Stromquelle 12 15 V versorgt werden Sollten Sie planen die EpiSensor mit Strom von einem Recorder zu versorgen verbinden Sie den Recorder mit unserem Kinemetrics Stromladeger t wie es in unserem User Manuel beschrieben ist Um die EpiSensor direkt mit Strom zu versorgen m ssen Sie ein Ladeger t 12 15 V welches mit allen Sicherheitsbedingunge ausgestattet ist benutzen OPTIONELLES STROMVERSORGUNGS LADEGER T In manchen F llen wird die EpiSensor eine lange Strecke von dem Recorder entfe
49. tallation Basics Requirements for Installation Listed below are the tools supplies and equipment required to install the EpiSensor in a typical configuration remotely from a Kinemetrics recorder and attached to that recorder via a cable However certain installations may require additional tools supplies or equipment depending on specific sites and needs Refer to Chapter 6 for information on long cable runs and other advanced installation options These instructions assume that all civil engineering work concrete pad attachment plate conduit etc have been finished and that the EpiSensor has been correctly configured for your installation at Kinemetrics If you need to change the full scale range output level refer to Chapter 3 before proceeding Required Tools EPISENSOR ES U USER GUIDE m Screwdrivers 1 8 flat blade 1 4 flat blade m 5 64 or 2 mm hex ball driver for zero adjustment E Long nose pliers m Wire strippers Soldering iron heat gun for installation with connector AC powered masonry percussion drill with 1 4 bit for drilling the anchor stud holes or fully charged battery powered drill m 7 16 open end wrench for 1 4 20 bolt DocuMENT 301925 REVISION A Hammer Safety glasses Required Supplies Required Adequate length and appropriate type of cable for connecting the EpiSensor to the recorder If a very long cable is required refer to Chapter 6 We recommend Kinemetrics P N
50. water pipe exposed section of re bar or an AC safety ground will probably be adequate The Grounds for Lightning and EMP Protection by Roger Block second edition published by Polyphaser Corporation provides an excellent practical discussion of grounding techniques Low Noise Operation This isolated configuration used for the EpiSensor will provide the lowest noise in the majority of installations In these cases the power commons are tied to earth ground at a single location in the recorder In high EMI environments depending on the system configuration and noise source the performance may be improved by connecting the power common to the case ground at the sensor In this scheme ground loops can be created that degrade the low noise performance If this occurs a possible solution is to create a hybrid ground This can be done by connecting the power common to the case ground using a 0 1uF 200V film capacitor EPISENSOR ES U USER GUIDE DOCUMENT 301925 REVISION A In sites exposed to very high levels of EMI RFI such as hilltop Antenna Farms additional EMI RFI protection may be required The Kinemetrics Protection Enclosure KMI P N 110480 Powering the EpiSensor If possible apply power to the system without connecting to the connector or pigtail on the EpiSensor and then verify that the power connections are correct Verify that 12V is present on the wire that will connect to Pin E on the optional connector or
51. with tweezers or your fingers Extra jumpers KMI P N 851152 can be obtained from Kinemetrics if it is desired to set additional configurations Setting the Full Scale Range The location of the various headers is shown in the following figures which show jumper positions for various output options and ranges The following table shows the sensitivities available for the jumper selectable ranges 20 EPISENSOR ES U USER GUIDE EI EPISENSOR ES U USER GUIDE DOCUMENT 301925 REVISION A Table 5 Range sensitivity calculations ull scale range 2 5V output 10V output SV output 20V output 1 4g 10 V g 40 V g 20 V g 80 V g 1 2g 5 V g 20 V g 10 V g 40 V g 2 5 Vig 10 Vig 5 Vig 20 Vig 1 25 Vig 5 Vig 2 5 Vig 10 Vig 0 625 V g 2 5 Vig 1 25 V g 5 Vig Voltage values are as measured across each channel s output pin A and B A is and B is either or ground depending on whether configured for a differential or single ended connection to the recorder For best performance a differential connection to the recorder should be used if the recorder supports differential input connections Figure 6 shows the jumper settings for the level of the sensor which determines the full scale range of the sensor Figure 7 shows the jumper settings for the sensor output voltage Figure 6 Jumper settings for sensor g level 21 DOCUMENT 301925 REVISION A Figure 7 Jumper settings for sensor output voltage 25V 10 F
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