USB-TEMP User's Guide - from Measurement Computing
Contents
1. 100 1 24 0 97 100 to 0 0 58 0 31 0 to 100 0 38 0 11 100 to 300 0 39 0 12 300 to 600 0 40 0 12 Note 8 Error shown does not include errors of the sensor itself The sensor linearization is performed using a Callendar Van Dusen linearization algorithm These specs are for one year while operation of the device is between 15 C and 35 C The specification does not include lead resistance errors for 2 wire RTD connections Please contact your sensor supplier for details on the actual sensor error limitations Note 9 Resistance values greater than 660 Q cannot be measured by the device in the RTD mode The 660 Q resistance limit includes the total resistance across the current excitation Ix pins which is the sum of the RTD resistance and the lead resistances Note 10 For accurate three wire compensation the individual lead resistances connected to the Ix pins must be of equal value Thermistor measurement accuracy Table 7 Thermistor measurement accuracy specifications Thermistor Temperature range C Maximum accuracy error C lx 10 pA 2252 Q 40 to120 0 05 3000 Q 40 to120 0 05 5000 Q 35 to120 0 05 10000 Q 25 to120 0 05 30000 Q 10 to120 0 05 Note 11 Error shown does not include errors of the sensor itself The sensor linearization is performed using a Steinhart Hart linearization algorithm These specs are for one year while operation of the device2. TEMP terminal blocks produce an additional thermocouple junction This junction creates a small voltage error term which must be removed from the overall sensor measurement using a cold junction compensation technique The measured voltage includes both the thermocouple voltage and the cold junction voltage To compensate for the additional cold junction voltage the USB TEMP subtracts the cold junction voltage from the thermocouple voltage The USB TEMP has two high resolution temperature sensors that are integrated into the design of the USB TEMP One sensor is located on the right side of the package and one sensor is located at the left side The CJC sensors measure the average temperature at the terminal blocks so that the cold junction voltage can be calculated A software algorithm automatically corrects for the additional thermocouples created at the terminal blocks by subtracting the calculated cold junction voltage from the analog input s thermocouple voltage measurement Increasing the thermocouple length If you need to increase the length of your thermocouple use the same type of thermocouple wires to minimize the error introduced by thermal EMFs Data linearization After the CJC correction is performed on the measurement data an on board microcontroller automatically linearizes the thermocouple measurement data using National Institute of Standards and Technology NIST linearization coefficients for the selected thermocoup
3. Table 9 Throughput rate specifications Number of input channels Maximum throughput 2 Samples second 2 S s on each channel 4 S s total 2 S s on each channel 6 S s total 2 S s on each channel 8 S s total 2 S s on each channel 10 S s total 2 S s on each channel 12 S s total 2 S s on each channel 14 S s total 2 S s on each channel 16 S s total COLA A Nn ASN Note 14 The analog inputs are configured to run continuously Each channel is sampled twice per second The maximum latency between when a sample is acquired and the temperature data is provided by the USB unit is approximately 0 5 seconds Digital input output Table 10 Digital input output specifications Parameter Specification Digital type CMOS Number of I O 8 DIOO through DIO7 Configuration Independently configured for input or output Power on reset is input mode Pull up pull down configuration All pins pulled up to 5 V via 47 kQ resistors default Pull down to ground GND also available Digital I O transfer rate Digital input 50 port reads or single bit reads per second typ software paced Digital output 100 port writes or single bit writes per second typ Input high voltage 2 0 V min 5 5 V absolute max Input low voltage 0 8 V max 0 5 V absolute min Output low voltage IOL 2 5 mA 0 7 V max Output high voltage 3 8 V min OH 2 5 mA Note 15
4. relative to GND pins 9 19 28 38 0 03 V min Note 18 The device has four current excitation outputs with I1 dedicated to the CHO CHI analog inputs I2 dedicated to CH2 CH3 13 dedicated to CH4 CHS and 14 dedicated to CH6 CH7 The excitation output currents should always be used in this dedicated configuration Note 19 The current excitation outputs are automatically configured based on the sensor thermistor or RTD selected Environmental Table 17 Environmental specifications Parameter Specification Operating temperature range 0 C to 70 C Storage temperature range 40 C to 85 C Humidity 0 to 90 non condensing Mechanical Table 18 Mechanical specifications Parameter Specification Dimensions L x W x H 128 52 x 88 39 x 35 56 mm 5 06 x 3 48 x 1 43 ft User connection length 3 m 9 84 ft max Signal connector Table 19 Signal connector specifications Parameter Specification Connector type Screw terminal Wire gauge range 16 AWG to 30 AWG 25 USB TEMP User s Guide Specifications Table 20 Screw terminal pinout Pin Signal Name Pin Description Pin Signal Name Pin Description 1 Hu CHO0 CH1 current excitation source 27 14 CH6 CH7 current excitation return 2 NC No connection
5. All ground pins pins 9 19 28 38 are common and are isolated from earth ground If a connection is made to earth ground when using digital I O and conductive thermocouples the thermocouples are no longer isolated In this case thermocouples must not be connected to any conductive surfaces that may be referenced to earth ground Memory Table 11 Memory specifications Parameter Specification EEPROM 1 024 bytes isolated micro reserved for sensor configuration 256 bytes USB micro for external application use 23 USB TEMP User s Guide Specifications Microcontroller Table 12 Microcontroller specifications Parameter Specification Type Two high performance 8 bit RISC microcontrollers USB 5V voltage Table 13 USB 5V voltage specifications Parameter Specification USB 5V VBUS input voltage 4 75 V min to 5 25 V max range Power Table 14 Power specifications Parameter Condition Specification Supply current USB enumeration lt 100 mA Supply current Continuous mode 140 mA typ Note 16 5V output voltage range pins 21 Connected to self powered hub Note 17 4 75 V min to and 47 5 25 V max 5V output current pins 21 Bus powered and connected to a self powered hub Note 17 10 mA max and 47 Isolation Measurement system to PC 500 VDC min Note 16 This is the total current requirement for the device which includes up to 10 mA for t
6. closes the installation is complete The USB LED should blink and then remain on This indicates that communication is established between the USB TEMP and your computer Caution Do not disconnect any device from the USB bus while the computer is communicating with the USB TEMP or you may lose data and or your ability to communicate with the USB TEMP USB TEMP User s Guide Installing the USB TEMP If the LED turns off If the LED is on but then turns off the computer has lost communication with the USB TEMP To restore communication disconnect the USB cable from the computer and then reconnect it This should restore communication and the LED should turn back on Configuring the hardware All hardware configuration options on the USB TEMP are programmable with software Use InstaCal to set the sensor type for each channel The configurable options dynamically update according to the selected sensor category Configuration options are stored on the USB TEMP s isolated microcontroller in EEPROM which is non volatile memory on the USB TEMP module Configuration options are loaded on power up Default configuration The factory default configuration is Disabled The Disabled mode disconnects the analog inputs from the terminal blocks and internally grounds all of the A D inputs This mode also disables each of the current excitation sources Warm up Allow the USB TEMP to warm up for 30 minutes before taking measur
7. constitute a channel pair although it is permissible to mix thermocouple types The USB TEMP provides two integrated cold junction compensation CJC sensors for thermocouple measurements and built in current excitation sources for resistive sensor measurements An open thermocouple detection feature lets you detect a broken thermocouple An on board microprocessor automatically linearizes the measurement data according to the sensor category The USB TEMP is a standalone plug and play module which draws power from the USB cable No external power supply is required All configurable options are software programmable The USB TEMP is fully software calibrated USB TEMP User s Guide Introducing the USB TEMP Functional block diagram USB TEMP functions are illustrated in the block diagram shown here USB 2 0 Microcontroller Isolated zea E 5V DC DC 500 V Isolation Barrier Precision 5V Ref Screw Terminal 12 12 24 bit A D B et Screw Terminal 24 bit A D CH6 CH7 gt Figure 1 Functional block diagram Connecting a USB TEMP to your computer is easy Installing a data acquisition device has never been easier The USB TEMP relies upon the Microsoft Human Interface Device HID class drivers The HID class drivers ship with every copy of Windows that is designed to work with USB ports We use the Microsoft HID because it is a standard and its performance del
8. ea neon ea bera epa be re ehe TTT HOL aea ense s npe ehe dee E hey Throughput Tate EE Digital input output s Rr E Bee RR E UE E EET EE e a Meh heehee USB specifications Current excitation outputs IXE 4 ee a irte tere A RO EE EE N NRS STTS rT MAIER ea aao Ea Seana VERVE a eaa ATE r en TH Signal connector ee ot EU eode ui EET cit io EU E Rie enter Declaration of Conformity eeeeeeeeeeeeeiies esses eese eene nnns enn snnt nnn tn asina nasa aio assa nass sisse nnn baye 27 Preface About this User s Guide What you will learn from this user s guide This user s guide describes the Measurement Computing USB TEMP data acquisition device and lists device specifications Conventions in this user s guide For more information Text presented in a box signifies additional information related to the subject matter Caution Shaded caution statements present information to help you avoid injuring yourself and others damaging your hardware or losing your data bold text Bold text is used for the names of objects on a screen such as buttons text boxes and check boxes italic text Italic text is used for the names of manuals and help topic titles and to emphasize a word or phrase Where to find more information Additional information about USB TEMP hardware is available on our website at www mccdag com You can also contact Measurement Computing Corporation with specific questions Kno
9. list price I O boards face some harsh environments some harsher than the boards are designed to withstand Contact MCC to determine your product s eligibility for this program 30 Day Money Back Guarantee Any Measurement Computing Corporation product may be returned within 30 days of purchase for a full refund of the price paid for the product being returned If you are not satisfied or chose the wrong product by mistake you do not have to keep it These warranties are in lieu of all other warranties expressed or implied including any implied warranty of merchantability or fitness for a particular application The remedies provided herein are the buyer s sole and exclusive remedies Neither Measurement Computing Corporation nor its employees shall be liable for any direct or indirect special incidental or consequential damage arising from the use of its products even if Measurement Computing Corporation has been notified in advance of the possibility of such damages Trademark and Copyright Information Measurement Computing Corporation InstaCal Universal Library and the Measurement Computing logo are either trademarks or registered trademarks of Measurement Computing Corporation Refer to the Copyrights amp Trademarks section on mccdaq conylegal for more information about Measurement Computing trademarks Other product and company names mentioned herein are trademarks or trade names of their respective companies 2014 Measuremen
10. require an excitation current to produce a voltage drop that can be measured differentially across the sensor The USB TEMP measures the sensor resistance by forcing a known excitation current through the sensor and then measuring differentially the voltage across the sensor to determine its resistance After the voltage measurement is made the resistance of the RTD is calculated using Ohms law the sensor resistance is calculated by dividing the measured voltage by the current excitation level Ix source The value of the Ix source is stored in local memory Once the resistance value is calculated the value is linearized in order to convert it to a temperature value The measurement is returned by software as a 32 bit floating point value in either temperature or resistance Data linearization An on board microcontroller automatically performs linearization on RTD and thermistor measurements RTD measurements are linearized using a Callendar Van Dusen coefficients algorithm you select DIN SAMA or ITS 90 Thermistor measurements are linearized using a Steinhart Hart linearization algorithm you supply the coefficients from the sensor manufacturer s data sheet USB connector The USB connector provides 5V power and communication No external power supply is required LED The LED indicates the communication status of the USB TEMP It uses up to 5 mA of current The table below lists the behavior of the LED LED Illumin
11. your thermocouple supplier for details on the actual thermocouple error Thermocouples must be connected to the device such that they are floating with respect to GND pins 9 19 28 38 The GND pins are isolated from earth ground so connecting thermocouple sensors to voltages referenced to earth ground is permissible as long as the isolation between the GND pins and earth ground is maintained When thermocouples are attached to conductive surfaces the voltage differential between multiple thermocouples must remain within 1 4 V For best results we recommend the use of insulated or ungrounded thermocouples when possible Semiconductor sensor measurement accuracy Table 5 Semiconductor sensor accuracy specifications Sensor type Temperature range C Maximum accuracy error C LM35 TMP35 or equivalent 40 to 150 0 50 Note 7 Error shown does not include errors of the sensor itself These specs are for one year while operation of the device is between 15 C and 35 C Please contact your sensor supplier for details on the actual sensor error limitations 21 USB TEMP User s Guide Specifications RTD measurement accuracy Table 6 RTD measurement accuracy specifications RTD Sensor Maximum accuracy error C Typical accuracy error C temperature C Ix 210 pA Ix 210 pA PT100 DIN US or 200 to 150 2 85 2 59 ITS 90 150 to
12. 0 628 GND Ground CHO sensor input con 39 Gu C7L CH7 sensor input CHO sensor input co 4 WO 6930 C7H CH7 sensor input CHO CH1 4 wire 2 sensor common 4W01 5 8 G 31 1c67 CH6 CH7 2 sensor common CHO CH1 2 sensor common co 6 Be 632 4W67 CH6 CH7 4 wire 2 sensor common CH1 sensor input C1H 7 S O M33 CBL CH6 sensor input CH1 sensor input C1L 8 8 8 34 Ceu CH6 sensor input Ground GND 9 S G 35 Nc No connection CHO CH1 current excitation return n 10 BS SS 14 CH6 CHT current excitation source CJC sensor PT __ CJC sensor CH2 CH3 current excitation source Sp t S S 13 CH4 CH5 current excitation return No connection NC 12 8 S GND Ground CH2 sensor input C2H 13 S S CSL CH5 sensor input CH2 sensor input C2L 14 S S C5H CH5 sensor input CH2 CH3 4 wire 2 sensor common 4W23 15 8 S IC45 CH4 CH5 2 sensor common CH2 CH3 2 sensor common IC23 16 G S 4W45 CH4 CHS 4 wire 2 sensor common CH3 sensor input C3H 17 WO S C4L CH4 sensor input CHS sensor input c3L 18 MG S C4H CHA sensor input Ground GND 19 SG S NC No connection CH2 CHS3 current excitation return 2 20 HG S 13 CH4 CH5 current excitation source Power output BV 23 89 S 5V 5V output Ground GND 22 HO 8 GND Ground DIO channel 0 DIOO 23 S S DIO7 DIO channel 7 DIO channel 1 Do 24 MG S DIO6 DIO channel 6 DIO channel 2 Do2 25 MO S DIOS DIO channel 5 DIO channel 3 pos 26 9 8 DIO4 DIO channel 4 Figure 2 USB TEMP scre
13. 1 If you move the switch to GND DIOO reads FALSE 0 dt GND Figure 11 Schematic showing switch detection by digital channel DIOO Caution All ground pins on the USB TEMP pins 9 19 28 38 are common and are isolated from earth ground If a connection is made to earth ground when using digital I O and conductive thermocouples the thermocouples are no longer isolated In this case thermocouples must not be connected to any conductive surfaces that may be referenced to earth ground For general information regarding digital signal connections and digital I O techniques refer to the Guide to DAQ Signal Connections available on our website at www mccdaq con signals signals pdf 16 Chapter 4 Functional Details Thermocouple measurements A thermocouple consists of two dissimilar metals that are joined together at one end When the junction of the metals is heated or cooled a voltage is produced that correlates to temperature The USB TEMP hardware level shifts the thermocouple s output voltage into the A D s common mode input range by applying 2 5 V to the thermocouple s low side at the C L input Always connect thermocouple sensors to the USB TEMP in a floating fashion Do not attempt to connect the thermocouple low side C L to GND or to a ground referencing resistor Cold junction compensation CJC When you connect the thermocouple sensor leads to the sensor input channel the dissimilar metals at the USB
14. 28 GND Ground 3 COH CHO sensor input 29 C7L CH7 sensor input 4 COL CHO sensor input 30 C7H CH7 sensor input 5 4WO01 CHO0 CH1 4 wire 2 sensor common 31 IC67 CH6 CH7 2 sensor common 6 IC01 CHO0 CH1 2 sensor common 32 4W67 CH6 CH7 4 wire 2 sensor common 7 C1H CH1 sensor input 33 CBL CH6 sensor input 8 CiL CHI sensor input 34 C6H CHG sensor input 9 GND Ground 35 NC No connection 10 H CHO0 CH1 current excitation return 36 14 CH6 CH7 current excitation source CJC sensor CJC sensor 11 12 CH2 CH3 current excitation source 37 I3 CH4 CH5 current excitation return 12 NC No connection 38 GND Ground 13 C2H CH2 sensor input 39 CBL CH5 sensor input 14 C2L CH2 sensor input 40 C5H CH5 sensor input 15 4W23 CH2 CH3 4 wire 2 sensor common 41 IC45 CH4 CH5 2 sensor common 16 IC23 CH2 CH3 2 sensor common 42 4W45 CH4 CH5 4 wire 2 sensor common 17 C3H CH3 sensor input 43 C4L CH4 sensor input 18 C3L CH3 sensor input 44 C4H CH4 sensor input 19 GND Ground 45 NC No connection 20 I2 CH2 CHG current excitation return 46 I3 CH4 CH5 current excitation source 21 45V Power output 47 45V Power output 22 GND Ground 48 GND Ground 23 DIOO DIO channel 0 49 DIO7 DIO channel 7 24 DIO1 DIO channel 1 50 DIO6 DIO channel 6 25 DIO2 DIO channel 2 51 DIO5 DIO channel 5 26 DIO3 DIO channel 3 52 DIO4 DIO channel 4 26 CE Declaration of Conformity Manufacturer Mea
15. USB TEMP Multi sensor Temperature Measurement User s Guide Document Revision 13 January 2014 Fa N PFa MEASUREMENT Copyright 2014 4 N Ra COMPUTING Your new Measurement Computing product comes with a fantastic extra Management committed to your satisfaction Thank you for choosing a Measurement Computing product and congratulations You own the finest and you can now enjoy the protection of the most comprehensive warranties and unmatched phone tech support It s the embodiment of our mission To provide data acquisition hardware and software that will save time and save money Simple installations minimize the time between setting up your system and actually making measurements We offer quick and simple access to outstanding live FREE technical support to help integrate MCC products into a DAQ system Limited Lifetime Warranty Most MCC products are covered by a limited lifetime warranty against defects in materials or workmanship for the life of the product to the original purchaser unless otherwise noted Any products found to be defective in material or workmanship will be repaired replaced with same or similar device or refunded at MCC s discretion For specific information please refer to the terms and conditions of sale Harsh Environment Program Any Measurement Computing product that is damaged due to misuse or any reason may be eligible for replacement with the same or similar device for 50 of the current
16. ation LED state Indication Steady green The device is connected to a computer or external USB hub Blinking green Data is being transferred The LED blinks three times when the device is first connected to a USB port on a computer or external hub Power output The two 5V terminals are isolated 500 VDC from the USB 5V Caution Each 5V terminal is an output Do not connect to an external power supply or you may damage the USB TEMP and possibly the computer 18 Chapter 5 Specifications All specifications are subject to change without notice Typical for 25 C unless otherwise specified Specifications in italic text are guaranteed by design Analog input Table 1 Generic analog input specifications Parameter Condition Specification A D converters Four dual 24 bit Sigma Delta type Number of channels 8 differential Input isolation 500 VDC minimum between field wiring and USB interface Channel configuration Software programmable to match sensor type Differential input Thermocouple 0 080 V voltage range for the RTD 0to 0 5 V been E Thermistor 0to2V categories Semiconductor sensor 0to2 5 V Absolute maximum COx through C7x relative to GND pins 24 V power on input voltage 9 19 28 38 24 V power off Input impedance 5 GQ min Input leakage current Open thermocouple detect disabled 30 nA max Open thermocouple detect enabled 105 nA
17. channels The analog input channels are therefore configured in four channel pairs with CHO0 CHI sensor inputs CH2 CH3 sensor inputs CH4 CHS5 sensor inputs and CH6 CH7 sensor inputs paired together This channel pairing requires the analog input channel pairs be configured to monitor the same category of temperature sensor Mixing different sensor types of the same category such as a type J thermocouple on channel 0 and a type T thermocouple on channel 1 is valid Channel configuration information is stored in the EEPROM of the isolated microcontroller by the firmware whenever any item is modified Modification is performed by commands issued over USB from an external application and the configuration is made non volatile through the use of the EEPROM The factory default configuration is Disabled The Disabled mode will disconnect the analog inputs from the terminal blocks and internally ground all of the A D inputs This mode also disables each of the current excitation sources Compatible sensors Table 3 Compatible sensor type specifications Parameter Specification Thermocouple J 210 C to 1200 C K 270 C to 1372 C R 50 C to 1768 C S 50 C to 1768 C T 270 C to 400 C N 270 C to 1300 C E 270 C to 1000 C B 0 C to 1820 C RTD 100 Q PT DIN 43760 0 00385 ohms ohm C 100 Q PT SAMA 0 003911 ohms ohm C 100 OPT ITS 90 IEC751 0 0038505 ohm
18. d in Chomerics Test Report EMI3876 04 Further testing was conducted by Chomerics Test Services Woburn MA 01801 USA in December 2008 Test records are outlined in Chomerics Test report EMI5215B 08 We hereby declare that the equipment specified conforms to the above Directives and Standards Pw Carl Haapaoja Director of Quality Assurance Measurement Computing Corporation 10 Commerce Way Suite 1008 Norton Massachusetts 02766 508 946 5100 Fax 508 946 9500 E mail info mccdag com www mccdag com
19. e USB TEMP in the thermistor mode The 180 kQ resistance limit includes the total resistance across the current excitation Ix pins which is the sum of the thermistor resistance and the lead resistance 12 USB TEMP User s Guide Sensor Connections Two wire configuration The easiest way to connect an RTD sensor or thermistor to the USB TEMP is with a two wire configuration since it requires the fewest connections to the sensor With this method the two wires that provide the RTD sensor with its excitation current also measure the voltage across the sensor Since RTDs exhibit a low nominal resistance measurement accuracy can be affected due to the lead wire resistance For example connecting lead wires that have a resistance of 1 Q 0 5 Q each lead to a 100 Q platinum RTD will result in a 1 measurement error With a two wire configuration you can connect either one sensor per channel pair or two sensors per channel pair Two wire single sensor A two wire single sensor measurement configuration is shown in Figure 4 rTu r JQ t OHHRSHRHEZ EQRERSCRRGS OGO OO OO OO L Figure 4 Two wire single RTD or thermistor sensor measurement configuration When you select a two wire single sensor configuration with InstaCal connections to C H and C L are made internally Two wire two sensor A two wire two sensor measurement configuration is shown in Figure 5 3t Tutt a OHRRSRHEHZ amp 98829 os o
20. e resistance of the RTD element with temperature A thermistor is a thermally sensitive resistor that is similar to an RTD in that its resistance changes with temperature thermistors show a large change in resistance that is proportional to a small change in temperature The main difference between RTD and thermistor measurements is the method used to linearize the sensor data RTDs and thermistors are resistive devices that require an excitation current to produce a voltage drop that can be measured differentially across the sensor The device has four built in current excitation sources I1 to 14 for measuring resistive type sensors Each current excitation terminal is dedicated to one channel pair The USB TEMP makes two three and four wire measurements of RTDs 100 platinum type and thermistors Use InstaCal to select the sensor type and the wiring configuration Once the resistance value is calculated the value is linearized in order to convert it to a temperature value A 32 bit floating point value in either temperature or resistance is returned by software RTD maximum resistance Resistance values greater than 660 cannot be measured by the USB TEMP in the RTD mode The 660 Q resistance limit includes the total resistance across the current excitation Ix pins which is the sum of the RTD resistance and the lead resistances Thermistor maximum resistance Resistance values greater than 180 kQ cannot be measured by th
21. ely before installing any software or hardware Unpacking As with any electronic device you should take care while handling to avoid damage from static electricity Before removing the USB TEMP from its packaging ground yourself using a wrist strap or by simply touching the computer chassis or other grounded object to eliminate any stored static charge If any components are missing or damaged contact us immediately using one of the following methods Knowledgebase kb mccdaq com Phone 508 946 5100 and follow the instructions for reaching Tech Support Fax 508 946 9500 to the attention of Tech Support Email techsupport mccdaq com For international customers contact your local distributor Refer to the International Distributors section on our website at www mccdaq com International Installing the software Refer to the Quick Start Guide for instructions on installing the software on the MCC DAQ CD This booklet is available in PDF at www mccdaq com PDFEmanuals DAQ Software Quick Start pdf Installing the hardware To connect the USB TEMP to your system turn your computer on and connect the USB cable to a USB port on your computer or to an external USB hub that is connected to your computer The USB cable provides power and communication to the USB TEMP When you connect the USB TEMP to a computer for the first time a Found New Hardware dialog opens when the operating system detects the device When the dialog
22. ements This warm up time minimizes thermal drift and achieves the specified rated accuracy of measurements For RTD or thermistor measurements this warm up time is also required to stabilize the internal current reference Calibrating the hardware The USB TEMP is fully calibrated via software InstaCal prompts you to run its calibration utility when you change from one sensor category to another Allow the USB TEMP to operate for at least 30 minutes before calibrating This warm up time minimizes thermal drift and achieves the specified rated accuracy of measurements Chapter 3 Sensor Connections The USB TEMP supports the following temperature sensor types Thermocouple types J K R S T N E and B Resistance temperature detectors RTDs 2 3 or 4 wire measurement modes of 100 Q platinum RTDs Thermistors 2 3 or 4 wire measurement modes Semiconductor temperature sensors LM36 or equivalent Sensor selection The type of sensor you select will depend on your application needs Review the temperature ranges and accuracies of each sensor type to determine which is best suited for your application Screw terminal pinout The device screw terminals are identified in Figure 2 Between each bank of screw terminals are two integrated CJC sensors used for thermocouple measurements CHO CH1 current excitation source 11 1 S Gu 14 CH6 CH7 current excitation return No connection nc 2M
23. he status LED Note 17 Self Powered Hub refers to a USB hub with an external power supply Self powered hubs allow a connected USB device to draw up to 500 mA Root Port Hubs reside in the PC USB Host Controller The USB port s on your PC are root port hubs All externally powered root port hubs desktop PC provide up to 500 mA of current for a USB device Battery powered root port hubs provide 100 mA or 500 mA depending upon the manufacturer A laptop PC that is not connected to an external power adapter is an example of a battery powered root port hub USB specifications Table 15 USB specifications Parameter Specification USB device type USB 2 0 full speed Device compatibility USB 1 1 USB 2 0 Device power capability Self powered 100 mA consumption max USB cable type A B cable UL type AWM 2725 or equivalent min 24 AWG VBUS GND min 28 AWG D D USB cable length 3 m 9 84 ft max 24 USB TEMP User s Guide Specifications Current excitation outputs Ix Table 16 Current excitation output specifications Parameter Specification Configuration 4 dedicated pairs 11 CHO CH1 12 CH2 CH3 13 CHA CH5 14 CH6 CH7 Thermistor 10 pA typ RTD 210 pA typ Current excitation output ranges Tolerance 5 typ Drift 200 ppm C Line regulation 2 1 ppm V max Load regulation 0 3 ppm V typ Output compliance voltage 3 90 V max
24. imately 40 C to 125 C where an accuracy of 2 C is adequate The temperature measurement range of a semiconductor sensor is small when compared to thermocouples and RTDs However semiconductor sensors can be accurate inexpensive and easy to interface with other electronics for display and control The USB TEMP makes high resolution measurements of semiconductor sensors and returns a 32 bit floating point value in either voltage or temperature Use InstaCal to select the sensor type LM35 TMP35 or equivalent and the sensor input channel to connect the sensor Wiring configuration Connect the semiconductor sensor to the USB TEMP using a single ended configuration as shown in Figure 10 The device provides 5V and GND pins for powering the sensor Figure 10 Semiconductor sensor measurement configuration 15 USB TEMP User s Guide Sensor Connections Digital I O connections You can connect up to eight digital I O lines to the screw terminals labeled DIOO to DIO7 You can configure each digital bit for either input or output All digital I O lines are pulled up to 5V with a 47 kQ resistor default You can request the factory to configure the resistor for pull down to ground if desired When you configure the digital bits for input you can use the USB TEMP digital I O terminals to detect the state of any TTL level input Refer to the schematic shown in Figure 11 If you set the switch to the 5V input DIOO reads TRUE
25. ion connect two sets of sense excitation wires at each end of the RTD or thermistor sensor This configuration completely compensates for any lead wire resistance and temperature change in lead wire resistance Connect your sensor with a four wire configuration when your application requires very high accuracy measurements Examples of a four wire single sensor measurement configuration are shown in Figure 7 and Figure 8 You can configure the USB TEMP with either a single sensor per channel or two sensors per channel pair Four wire single sensor A four wire single sensor connected to the first channel of a channel pair is shown in Figure 7 O EEZ Z O 268606 Figure 7 Four wire single RTD or thermistor sensor measurement configuration 14 USB TEMP User s Guide Sensor Connections A four wire single sensor connected to the second channel of a channel pair is shown in Figure 8 T F sp Q TL GOZ T ETLE OODDODOOOOO Figure 8 Four wire single RTD or thermistor sensor measurement configuration A four wire two sensor measurement configuration is shown in Figure 9 I zitr uo OS3E EZ TXT Z 9585208604 OODDODOOOOO IL Figure 9 Four wire two RTD or thermistor sensors measurement configuration When configured for four wire two sensor mode both sensors must be connected to obtain proper measurements Semiconductor sensor measurements Semiconductor sensors are suitable over a range of approx
26. ion seieren M 14 STT TTT 14 Semiconductor sensor measurements ceeeceenceceseceeceeceseceeceecsacceeceecsaceeseeecsaeceeeeecsaecseeecsaeceeeeecsaeeeeeeeenaeeees 15 Wiring configuration 1 iret e eere iei EE rne aee ete be eot ce dtd e 15 Digital l O connections nri ie De Pere re TEDT R E OTRE OTER ESS 16 Chapter 4 Functional Details Thermocouple measurements 4 etre rhe deeper eae ee pepe rte eee EE a eese ES ek ee bene aree pene penne p Cold junction compensation CIC 1 Reel ire Pe eed e ebbe Data linearization sess Open thermocouple detection OTD RTD and thermistor measurements aE R E T K e docegsuevee T A ees WS BaCOnNe ClO Ric ete reete teen een ise ei UM Dl LEA USB TEMP User s Guide Power outpUut optet EOD RUE TET RAT TETE TEE t AREE RERUM ERE choad 18 Chapter 5 SPeCifiCatiONs eec u Analos TnpUt s EEEE ERO ORB EC ER RRAREREREOR NC EREECO T OTRO REOR RERO E E Channel Conf Purations En Compatible sensors hoguea Me EE Thermocouple measurement accuracy sorsas esaea eee ee e ESSEN S e SERRE 2 CHR CH ERN AEREE XR TERR UNDER R sieve vesevanceereveugeoversuneesvterss Semiconductor sensor measurement accuracy RTD measurement accur ys sce vues at E A A A E AEE d eMe rt NERA RE ERN Thermistor measurement accuracy 7 eee etre rre roten eee t
27. is between 15 C and 35 C The specification does not include lead resistance errors for 2 wire thermistor connections Please contact your sensor supplier for details on the actual sensor error limitations Total thermistor resistance on any given channel pair must not exceed 180 kO Typical resistance values at various temperatures for supported thermistors are shown in Table 8 Table 8 Typical thermistor resistance specifications Temp 2252 Q thermistor 3000 Q B KO 10 kQ 30 kQ C thermistor thermistor thermistor thermistor 40 76 KQ 101 KQ 168 kQ 240 kQ Note 12 885 kQ Note 12 35 55 kQ 73 KQ 121 kQ 179 kQ 649 kQ Note 12 30 40 kQ 53 kQ 88 kQ 135 kQ 481 kO Note 12 25 29 kQ 39 kQ 65 kQ 103 kQ 360 kQ Note 12 20 22 kQ 29 kQ 49 KQ 79 kQ 271 KQ Note 12 15 16 kQ 22 kQ 36 kQ 61 kQ 206 kQ Note 12 10 12 kQ 17 kQ 28 kQ 48 KQ 158 kQ 5 9 5 kQ 13 kQ 21 kQ 37 kQ 122 kQ 0 7 4 KQ 9 8 kQ 16 kQ 29 kQ 95 kQ 22 USB TEMP User s Guide Specifications Note 12 Resistance values greater than 180 kQ cannot be measured by the device in the thermistor mode The 180 KQ resistance limit includes the total resistance across the current excitation Ix pins which is the sum of the thermistor resistance and the lead resistances Note 13 For accurate three wire compensation the individual lead resistances connected to the Ix pins must be of equal value Throughput rate
28. ivers full control and maximizes data transfer rates for your USB TEMP No third party device driver is required The USB TEMP is plug and play There are no jumpers to position DIP switches to set or interrupts to configure You can connect the USB TEMP before or after you install the software and without powering down your computer first When you connect an HID to your system your computer automatically detects it and configures the necessary software You can connect and power multiple HID peripherals to your system using a USB hub You can connect your system to various devices using a standard four wire cable The USB connector replaces the serial and parallel port connectors with one standardized plug and port combination You do not need a separate power supply module The USB automatically delivers the electrical power required by each peripheral connected to your system Data can flow two ways between a computer and peripheral over USB connections 7 Chapter 2 Installing the USB TEMP What comes with your shipment The following items are shipped with the USB TEMP Hardware USB TEMP USB cable Software MCC DAQ CD Documentation In addition to this hardware user s guide you should also receive the Quick Start Guide This booklet provides an overview of the MCC DAQ software you received with the device and includes information about installing the software Please read this booklet complet
29. le type The measurement data is then output as a 32 bit floating point value in the configured format voltage or temperature Open thermocouple detection OTD The USB TEMP is equipped with an open thermocouple detection for each analog input channel With OTD any open circuit or short circuit condition at the thermocouple sensor is detected by the software An open channel is detected by driving the input voltage to a negative value outside the range of any thermocouple output The software recognizes this as an invalid reading and flags the appropriate channel The software continues to sample all channels when OTD is detected Input leakage current With open thermocouple detection enabled 105 nA max of input leakage current is injected into the thermocouple This current can cause an error voltage to develop across the lead resistance of the thermocouple that is indistinguishable from the thermocouple voltage you are measuring 17 USB TEMP User s Guide Functional Details You can estimate the error voltage with this formula error voltage resistance of the thermocouple x 105 nA To reduce the error reduce the length of the thermocouple to lower its resistance or lower the AWG of the wire by using a wire with a larger diameter With open thermocouple detection disabled 30 nA max of input leakage current is injected into the thermocouple RTD and thermistor measurements RTDs and thermistors are resistive devices that
30. max Normal mode rejection fix 60 Hz 90 dB min ratio Common mode rejection fiw 50 Hz 60 Hz 100 dB min ratio Resolution 24 bits No missing codes 24 bits Input coupling DC Warm up time 30 minutes min Open thermocouple detect Automatically enabled when the channel pair is configured for thermocouple sensor The maximum open detection time is 3 seconds CJC sensor accuracy 15 C to 35 C 30 25 C typ 30 5 C max 0 C to 70 C 1 0 C to 0 5 C max 19 USB TEMP User s Guide Specifications Channel configurations Table 2 Channel configuration specifications Sensor Category Condition Max number of sensors all channels configured alike Disabled Thermocouple 8 differential channels Semiconductor sensor 8 differential channels RTD and thermistor 2 wire input configuration with a single sensor per channel pair 4 differential channels 2 wire input configuration with two sensors per channel pair 8 differential channels 3 wire configuration with a single sensor per channel pair 4 differential channels 4 wire input configuration with a single sensor per channel pair 4 differential channels 4 wire input configuration with two sensors per channel pair 8 differential channels Note 1 Note 2 Note 3 Internally the device has four dual channel fully differential A Ds providing a total of eight differential
31. n feature is available for each analog input which automatically detects an open or broken thermocouple Use InstaCal to select the thermocouple type J K R S T N E and B and one or more sensor input channels to connect the thermocouple 11 USB TEMP User s Guide Sensor Connections Wiring configuration Connect the thermocouple to the USB TEMP using a differential configuration as shown in Figure 3 O Z EQERES amp 8G x a Figure 3 Typical thermocouple connection The USB TEMP GND pins are isolated from earth ground so connecting thermocouple sensors to voltages referenced to earth ground is permissible as long as the isolation between the GND pins 9 19 28 38 and earth ground is maintained When thermocouples are attached to conductive surfaces the voltage differential between multiple thermocouples must remain within 1 4 V For best results we recommend the use of insulated or ungrounded thermocouples when possible Maximum input voltage between analog input and ground The absolute maximum input voltage between an analog input and the isolated GND pins is 25 VDC when the USB TEMP is powered on and 40 VDC when the USB TEMP is powered off If you need to increase the length of your thermocouple use the same type of thermocouple wires to minimize the error introduced by thermal EMFs RTD and thermistor connections A resistance temperature detector RTD measures temperature by correlating th
32. ooooooooOo Figure 5 Two wire two RTD or thermistor sensors measurement configuration When you select a two wire two sensor configuration with InstaCal connections to C H first sensor and C H C L second sensor are made internally When configured for two wire mode both sensors must be connected to obtain proper measurements 13 USB TEMP User s Guide Sensor Connections Three wire configuration A three wire configuration compensates for lead wire resistance by using a single voltage sense connection With a three wire configuration you can connect only one sensor per channel pair A three wire measurement configuration is shown in Figure 6 W CH O Z a liu C H C L 4 C H C L GND Figure 6 Three wire RTD or thermistor sensor measurement configuration When you select a three wire sensor configuration with InstaCal the USB TEMP measures the lead resistance on the first channel C H C L and measures the sensor itself using the second channel C H C L This configuration compensates for any lead wire resistance and temperature change in lead wire resistance Connections to C H for the first channel and C H C L of the second channel are made internally Three wire compensation For accurate three wire compensation the individual lead resistances connected to the I pins must be of equal resistance value Four wire configuration With a four wire configurat
33. s ohm C Thermistor Standard 2 252 Q through 30 000 Q Semiconductor IC LM35 TMP35 or equivalent 20 USB TEMP User s Guide Specifications Accuracy Thermocouple measurement accuracy Table 4 Thermocouple accuracy specifications including CJC measurement error Sensor type Maximum error C Typical error C Temperature range C J 1 499 0 507 210 to 0 0 643 0 312 0 to 1200 K 1 761 0 538 210 to 0 0 691 0 345 0 to 1372 S 2 491 0 648 50 to 250 1 841 0 399 250 to 1768 1 R 2 653 0 650 50 to 250 1 070 0 358 250 to 1768 1 B 1 779 0 581 250 to 700 0 912 0 369 700 to 1820 E 1 471 0 462 200 to 0 0 639 0 245 0 to 1000 T 1 717 0 514 200 to 0 0 713 0 256 0 to 600 N 1 969 0 502 200 to 0 0 769 0 272 0 to 1300 Note 4 Thermocouple measurement accuracy specifications include linearization cold junction Note 5 Note 6 compensation and system noise These specs are for one year or 3000 operating hours whichever comes first and for operation of the device between 15 C and 35 C For measurements outside this range add 0 5 to the maximum error shown There are CJC sensors on each side of the module The accuracy listed above assumes the screw terminals are at the same temperature as the CJC sensor Errors shown do not include inherent thermocouple error Please contact
34. source for channel 0 and channel 1 2 is the current excitation source for channel 2 and channel 3 3 is the current excitation source for channel 4 and channel 5 4 4 is the current excitation source for channel 6 and channel 7 Four wire two sensor common terminals 4W01 to 4W67 These terminals are used as the common connection for four wire configurations with two RTD or thermistor sensors Two sensor common terminals IC01 to IC67 These terminals are used as the common connection for two wire configurations with two RTD or thermistor sensors Digital terminals DIOO to DIO7 You can connect up to eight digital I O lines to the screw terminals labeled DIOO to DIO7 Each terminal is software configurable for input or output CJC sensors The USB TEMP has two built in high resolution temperature sensors One sensor is located on the right side of the package and one sensor is located at the left side Power output terminals 5V The two 5V output terminals are isolated 500 VDC from the USB 5V Ground terminals GND The six ground terminals GND provide a common ground for the input channels and DIO bits and are isolated 500 VDC from the USB GND Thermocouple connections The USB TEMP makes fully differential thermocouple measurements without the need of ground referencing resistors A 32 bit floating point value in either a voltage or temperature format is returned by software An open thermocouple detectio
35. surement Computing Corporation Address 10 Commerce Way Suite 1008 Norton MA 02766 USA Category Electrical equipment for measurement control and laboratory use Measurement Computing Corporation declares under sole responsibility that the product USB TEMP to which this declaration relates is in conformity with the relevant provisions of the following standards or other documents EC EMC Directive 2004 108 EC General Requirements EN 61326 1 2006 IEC 61326 1 2005 Emissions EN 55011 2007 CISPR 11 2003 Radiated emissions Group 1 Class A EN 55011 2007 CISPR 11 2003 Conducted emissions Group 1 Class A Immunity EN 61326 1 2006 Table 3 EC 61000 4 2 2001 Electrostatic Discharge immunity EC 61000 4 3 2002 Radiated Electromagnetic Field immunity To maintain compliance to the standards of this declaration the following conditions must be met The host computer peripheral equipment power sources and expansion hardware must be CE compliant All T O cables must be shielded with the shields connected to ground T O cables must be less than 3 meters 9 75 feet in length The host computer must be properly grounded Equipment must be operated in a controlled electromagnetic environment as defined by Standards EN 61326 1 2006 or IEC 61326 1 2005 Declaration of Conformity based on tests conducted by Chomerics Test Services Woburn MA 01801 USA in May 2004 Test records are outline
36. t Computing Corporation All rights reserved No part of this publication may be reproduced stored in a retrieval system or transmitted in any form by any means electronic mechanical by photocopying recording or otherwise without the prior written permission of Measurement Computing Corporation Notice Measurement Computing Corporation does not authorize any Measurement Computing Corporation product for use in life support systems and or devices without prior written consent from Measurement Computing Corporation Life support devices systems are devices or systems that a are intended for surgical implantation into the body or b support or sustain life and whose failure to perform can be reasonably expected to result in injury Measurement Computing Corporation products are not designed with the components required and are not subject to the testing required to ensure a level of reliability suitable for the treatment and diagnosis of people HM USB Temp docx Table of Contents Preface About this User s Guide 0 c cctcc ste eeseeeeeseeessaeeeseeeseneeseeeesaaesesneesesneeseaesusaesasneeessneessaesesnnesaaneeeeenens 5 What you will learn from this user s guide sse sese eee 5 Conventions in this user s guide Where to find more information Chapter 1 Introducing the USB TEMP T 6 Functional block diagram setes entei era e O EE AE A e E a o R E O EE 7 Connecting a USB TEMP to your computer is eas
37. w terminal pin numbers Use 16 AWG to 30 AWG wire for your signal connections Tighten screw terminal connections When making connections to the screw terminals be sure to tighten the screw until tight Simply touching the top of the screw terminal is not sufficient to make a proper connection Sensor input terminals COH COL to C7H C7L You can connect up to eight temperature sensors to the differential sensor inputs COH COL to C7H C7L Supported sensor categories include thermocouples RTDs thermistors or semiconductor sensors Do not mix sensor categories within channel pairs You can mix thermocouple types J K R S T N E and B within channel pairs however 10 USB TEMP User s Guide Sensor Connections Do not connect two different sensor categories to the same channel pair The USB TEMP provides a 24 bit A D converter for each channel pair Each channel pair can monitor one sensor category To monitor a sensor from a different category connect the sensor to a different channel pair input terminals Current excitation output terminals 11 to 14 The USB TEMP has four dedicated pairs of current excitation output terminals I1 to 14 These terminals have a built in precision current source to provide excitation for the resistive sensors used for RTD and thermistor measurements Each current excitation terminal is dedicated to one pair of sensor input channels 1 is the current excitation
38. wledgebase kb mccdaq com Phone 508 946 5100 and follow the instructions for reaching Tech Support Fax 508 946 9500 to the attention of Tech Support Email techsupport mccdaq com Chapter 1 Introducing the USB TEMP The USB TEMP is a USB 2 0 full speed temperature measurement module that is supported under popular Microsoft Windows operating systems The USB TEMP is fully compatible with both USB 1 1 and USB 2 0 ports The USB TEMP provides eight differential input channels that are software programmable for different sensor categories including thermocouple RTDs thermistors and Semiconductor sensors Eight independent TTL compatible digital I O channels are provided to monitor TTL level inputs and to communicate with external devices The digital I O channels are software programmable for input or output You can take measurements from four sensor categories Thermocouple types J K R S T N E and B Resistance temperature detectors RTDs 2 3 or 4 wire measurements of 100 Q platinum RTDs Thermistors 2 3 or 4 wire measurements Semiconductor temperature sensors LM35 TMP35 or equivalent The USB TEMP provides a 24 bit analog to digital A D converter for each pair of differential analog input channels Each pair of differential inputs constitutes a channel pair You can connect a different category of sensor to each channel pair but you can not mix categories among the channels that
39. y sese ee ee eee 7 Chapter 2 Installing the USB TEMP TT 8 What comes with your ShipMent oo eee ee eee 8 Hardware 8 Software es 8 DOCUIMENEALION 5 xas S P 8 Unp ckinp oto oec ERO DEIN p E E E E Pe DER edes 8 Installing the SO tWATe 4i Inm tt RI ERE EG coty EE PSU EH EU ET n ATE PO e Een 8 Instalhing the hardwate ote oU ettet sundown dede pn t iatemd qe ten iiie i ep ere te 8 Configuring the hardware e Uere m tete Eutr ett e E eere co ipenan PUNIRE NP ED E RUMP ERES EUR 9 Calibrating the hardware ettet e cei e E E ce re YE A E Peta eee 9 Chapter 3 Sensor Connect ONS oiiaii teneret on iei Heo TRT S aaae SORTE Screw terminal pinout E Sensor input terminals COH COL to C7H C7L ceccceccsscsesseseesseeseceseeseeesecseceseesecesesseceaeesecesecseceaeesesesecseeeaeeeeeaeeeeeaeeaes Current excitation output terminals 411 to H4 sese Four wire two sensor common terminals 4W01 to 4W67 Two sensor common terminals ICO1 to IC67 Digital terminals DIOO to DIOT ai r o EOT O EE E TO E E E E Ea CJC SENSOTS 25 see eaei eass Power output terminals 5V Ground terna S GND e a a ran a aa ra aa eE eaa aae a e e nees aer an area nean esanak Thermocouple connections seen coves E E E EE E E E E E urna epe ee reden tI 11 Winne Conf TTT eT an RE EE vasa E E T O UU ERE EO EA eae 12 RTD and thermistor connections esrin n a a i a a e et KTT 12 RL TTT STT 13 Thr wire configurat
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