9030 Plus™ CORRATER INSTRUMENT USER MANUAL
Contents
1. 5 LK f 2 ie X po HT z j HT 5 pen TE LK LK UNT c F A LK f A gt 3LK f Only required for CORRO TE RATER pr Figure 3 5 Probe Cable Color Connections To minimize pickup of electromagnetic interference care should be taken to route cables clear of heavy current cables and devices Routing probe cables inside grounded conduit tubing provides the best immunity against EM interference For conduit installations AC power wires should not be in the same conduit as the probe cables 14 9030 Plus Reference Manual 4 20 Loops Data Logger Setpoint Relay and AC Power Connections Refer to Figure 3 2 the electrical wiring diagram for the various cable connections required to interface the 9030 Plus The six 4 20 milliamp loops are accessible via the twelve pin connector P1 located on the circuit board From top to bottom the loops are identified loop 1 through loop 6 Loop 1 is closest to the corner ofthe circuit board CAUTION The 9030 Plus instrument sources current to these loops and no external loop power should be applied The Data Logger is accessible through the 3 pin RS232 connector Ifthe set point relay function is used connect an external alarm circuit to the PA connector Common and Normally Closed NC or the Common and Normally Open2. ReadDate Rate 10 10 2007 2 43 12 PM 5 0400 100 1000 10 10 2007 3 13 12 PM 5 0400 100 1000 10 10 2007 3 43 12 PM 5 0400 100 0000 10 10 2007 4 13 12 PM 5 0400 100 1000 10 10 2007 4 43 12 PM 5 0400 100 0000 10 10 2007 5 13 12 PM 5 0500 100 0000 10 10 2007 5 43 12 PM 15 0500 100 0000 10 10 2007 6 13 12 PM 5 0500 100 0000 10 10 2007 6 43 12 PM 5 0500 100 0000 10 10 2007 7 13 12 5 0500 100 0000 10 10 2007 7 43 12 PM 5 0500 100 0000 10 10 2007 8 13 12 PM 5 0400 100 0000 ojojojojojojojojojojo 1011 2007 If you wish to accept the batch Click Close then Batch The program will ask Accept Batch x Click Yes to accept the data You should see the following 44 9030 Plus Reference Manual 115 CORRDATA Plus Demo Site oj Eile View Preferences Window Help 22 This list below represents batch data which has been received from the device Please select an action to perform for each of the items requiring review Merged Data 1 Batch Batch Group Unit Readina Last Recorded __ Status Reject All Accept Batch Reject Batch Current Site C Program Files ACS CORRDATA PLUS Demo SIT 1101122007 2 Now the data is in Merged Data 1 Batch Note the data is uploaded to computer the old data from the 9030 Plus is erased So be sure to save the batch if
3. Select Method drop down box and click a blue check mark in the left hand box as shown below 5 CORRDATA Plus Demo Site CIE x Ele View Preferences Window Help 22v 0890449 Select Device Configure Device C RDC Select Method 3030 Plus Probe 1 Close 9030 Plus Select a Complete Group or an Individual Probe from the list below by clicking in the first column 9030 Plus Probe 1 Demo Location 9030 Plus Probe 2 Demo Location Configuring an RCS 9030 Plus Probe 1 10 10 2007 2 39 Now press the Data Log key on the front of the 9030 press the Up arrow on the front of the unit to select Probe 1 then click Configure Device on the Corrdata Plus screen The 9030 will display COMMUNICATING PLEASE WAIT You may see this screen if Probe 1 was configured before Corrdata Plus Device Configuration X RDC is already configured Click to proceed to halt operation F Cancel Click to have the unit accept the new configuration Corrdata Plus Device Configuration X 1 RDC will be configured with the time from the a eres 1 CORRDATA Plus Demo Site 900 adress e Select Device Mate onn C BDC Configuring a 9030 Plus Probe 1 9030 PL ped Select a Fetching tag data Configuring 1 selected devices Inbox
4. NO terminals Relay connections Common to NC open circuit when either the corrosion rate or imbalance set points are exceeded and relay connections Common to NO close circuit when either set point is exceeded Ifthe AC power to the instrument is to be applied through conduit tubing the factory installed AC power cord will have to be removed Damage to the instrument could result if the AC power is not wired correctly The important thing to remember is that the ground terminal ofthe 3 wire power cable connects to the center terminal of P6 located inside the instrument The white wire is connected to the left terminal and the black wire is connected to the right terminal closest to the corner of the board Refer to figure 3 2 for further information 15 Chapter 4 Operation GENERAL The 9030 Plus is intended for continuous corrosion monitoring of cooling water systems and therefore does not require operator actions for operation other than those required for initial setup Once the initial instrument setup is performed the selections remain in effect until changed on the front panel by the operator If the power to the unit is lost or switched off the operational settings are stored in non volatile memory so that the unit configuration parameters will not need resetting when the power is restored When the data logger function is used the data must be periodically retrieved by a personal computer for analysis When the instrument is swi
5. 3 Probe Orientation Relative to 12 3 4 Probe Orientation at Tee Spe de 12 3 0 Probe Cable Color Connections ais US Ste 13 Table Page 5 1 CORRATER Multiplier 22 Appendix A Page 1 Equivalent Circuit of LPR Probe sil tesa ae Re aea gore qu rib cb ups ade S Ud 47 2 Typical LPR Current vs Time Decay Curve Pa dened 48 A 3 Operating Rate of LPR Instruments Corrosion Rate vs Solution Conductivity ss 49 A 4 Rohrback Cosasco 3 Electrode Probe set ec bed A Re de ne CN 50 Chapter 1 Introduction GENERAL The 9030 Plus single or two channel CORRATER instrument is a field installed corrosion monitor for cooling process or potable water systems The 9030 Plus CORRATER system 15 designed to help improve facility operations by enabling the user to directly monitor corrosion rate imbalance and temperature all automatically and continuously without operator intervention The display on the unit is autoranging to maintain high sensitivity regardless ofthe parameter being measured The information may also be data logged when CORRDATA Plus software is used to configure the instrument and retrieve data Figure 1 1 Front View of 9030 Plus Unit 2 9030 Plus Reference Manual CORRATER systems operate on the fundamental principle that a metal corroding through oxidation will generate a small e
6. CDA 687 Alum Brass Arsenical C70610 CDA 706 90 10 Copper Nickel 180 71500 CDA 715 70 30 Copper Nickel EN 41300 AISI 4130 Alloy Steel EN L50045 Lead N04400 Monel 400 Nickel 16 N05500 Monel K 500 Nickel E N06022 Hastelloy C22 os N06600 Inconel 600 Nickel oss NEN oo 1 1 1 1 1 1 1 1 0 0 N08020 Carpenter 20 CB3 SST 0 0 N08800 Incolloy 800 9 8 0 6 6 4 6 8 0 5 0 8 9 9 8 8 8 0 7 8 8 2 0 0 0 7 3 4 5 b 8 9 8 N08825 Incolloy 825 531803 2205 Duplex Stainless Steel 532750 2507 Duplex Stainless Steel Ces ec je Chapter 5 Maintenance 23 Electrodes should be replaced when the diameter is reduced 1 32 inch 0 794 mm or more CORRATER electrodes nominally 3 16 inch 4 76 mm diameter and 1 1 4 inch 31 75 mm long when new As corrosion occurs on the electrodes their diameter decreases and begins significantly affecting corrosion readings accuracy Do not use pliers to install new or cleaned electrodes on a standard probe body The electrodes should be screwed on the mounting studs only finger tight slightly compressing the O rings at the base ofthe studs Handle the electrodes with a clean cloth or paper towel to avoid body oil contamination If contamination occurs use a suitable degreaser to clean the electrodes Electrode Pretreatment Electrode pretreatment may be necessary in some instances but only recommended if using the s
7. Installation 11 L 4 C Fi ps gi rn mt I4 rc a a Mas a a C a a a nm a a 158 E a acs A L a 7 HITE a 2 BLACH a amu E mum EEN BLACK AY E LACK HITE LACH F 4 OMM ET POINT AC POWE ELA Figure 3 2 Installation Wiring Connections CORRATER Probes The 9030 Plus is intended to be used with any standard 2 electrode CORRATER probes Three electrode probes can also be used but for simplicity and economy it is recommended that 2 electrode probes be used Probes with replaceable cylindrical electrodes are generally referred to as standard probes and probes with disc electrodes are referred to as flush probes because the electrodes are flush with the end surface ofthe probe The probes are available in many designs including fixed adjustable retractable and retrievable mounting configurations 12 9030 Plus Reference Manual Also probe electrodes are availabl
8. The imbalance anodic cathodic and SRC Solution Resistance Compensation measurements are each allocated a portion of the cycle time The factory default is 5 0 minutes An automatic cycle time may also be selected The AUTO cycle time is recommended for use with lower conductivity waters i e less than 10 micromhos uS MULTIPLIER The alloy correction multipliers independently set for each probe are adjustable from 0 25 to 3 0 in 0 01 increments The factory default is 1 00 PROBE TYPE The available selections are 2 3 electrode CORRATER probes without temperature 2 3 ELEC NO TEMP and 2 3 electrode CORROTEMP CORRATER probes with temperature 2 3 ELEC WITH TEMP The factory default is 2 5 ELEC NO TEMP PROBE ELEMENT STYLE The available selections are STANDARD and FLUSH The factory default is STANDARD PROBE RATE 4 20 LOOP F S This defines the full scale for the 4 20 mA loop associated with the probe The full scale settings are 1 2 5 10 20 50 100 200 500 or 1000 MPY or the metric equivalents The factory default is 20 MPY PROBE IMBALANCE 4 20 LOOP F S This defines the full scale for the 4 20 mA loop associated with the probe The full scale settings are 1 2 5 10 20 50 100 200 500 or 1000 imbalance units The factory default is 20 IU Imbalance Units PROBE RATE SETPOINT If the measured corrosion rate on a channel exceeds the programmed setpoint it causes the setpoint relay to close and the displayed rate to fla
9. analyze graph and report the data Use these sections as required 26 9030 Plus Reference Manual Helpful Hints Please remember the data logger is configured separately from the 9030 Plus For example when you change the multiplier in the 9030 Plus front panel configuration to be 2 0 and correspond to copper the same change must be made to the probe configuration in the CORRDATA Plus Software Important When retrieving data from the 9030 Plus CORRDATA Software the Read from Device box must be checked ON before dumping the data Also when configuring the 9030 Plus from C ORRDATA Plus Software the Configure Device box must be checked ON before configuring the unit 27 setting Up Corrdata Plus for 9030 Plus Data Logging NOTE Corrdata Plus sets up the Data Logging portion of the unit ONLY Some data logging set ups may need changes to the unit set up via the unit s front panel To set up a 9030 Plus for data logging using Corrdata Plus First create a new site 1 CORRDATA Plus Bl x File Help uv usse 2 29 Open an Existing Site Create a New Site Question and Answer Select an option from the choices above Enter a descriptive name for this site Demo Site The site name given will appear in the Site Name box of Select an Existing Site Screen Cancel lt Back ETIN Finished 28 9030 Plus Reference Manual Then be sure that the corre
10. during this period After the stabilization period it is recommended that cycle time be set to automatic The automatic mode looks at the signal decay characteristic and takes a reading as soon as it stabilizes A manual override of cycle time is also available After noting the corrosion rate reading reduce the cycle time to 5 minutes Ifthe corrosion rate reading is not significantly higher than the first reading the cycle time may be left at 5 minutes If the second reading is significantly higher than the first reading it is recommended that the cycle time be re set sequentially to 10 15 20 etc until the corrosion rate reading reaches its minimum value See Appendix A 20 9030 Plus Reference Manual Multiplier Selection The 9030 Plus calibration has been normalized to use a multiplier value of 1 0 when standard carbon steel probe electrodes are used Normal size electrodes are 5 square centimeters for standard electrodes and 0 5 square centimeters for flush electrodes If alternate electrode sizes are used or other alloys the multiplier value will need to be appropriately changed to provide accurate corrosion rate readings Table 5 1 lists the recommended multiplier settings when using normal size electrodes for various commonly used electrode materials The multiplier should be set to the value nearest the recommended setting If electrodes other than RCS standard 5 cm or flush 0 5 cm electrodes are used
11. the data is good Also the 9030 Plus screen will display STANDBY TO READ after re configuration and after data upload Once the cycle time that was set on the front panel is complete the unit will then display probe readings To upload the data for Probe 2 if the unit is set up for 2 probe operation 155 CORRDATA Plus Demo Site File View Preferences Window Help 12 5 9 082906 58 82 4 Receive Data C Mate C 9030Plus C Manual Entry Bead from Device Select Method 04 Close Receive Data To Group Demo Current Site C Program Files RCS CORRDATA PLUS Demo SIT 45 Press the Data Log key then press Down arrow Probe 2 Then click Read From Device The 9030 will display COMMUNICATING PLEASE WAIT When complete the computer should display the following Corrdata Plus X 1 9030 Plus Probe 2 Data reception complete The following should appear 15 CORRDATA Plus Demo Site Iof x File View Preferences Window Help gn 082904 44 amp Receive Data Manager This list below represents batch data which has been received from the device Please select an action to perform for each of the items requiring review Merged Data Batch Group Unit Readina Last Recorded Accept All 1 Demo 2 Clean data Reject All Accept Batch Reject Batch View Batch Repeat the Batch Vie
12. the multiplier can be adjusted to compensate for the size Generally the multiplier value is inversely proportional to the electrode area For example if 9 cm electrodes were used with the probe type set to standard the alloy multiplier value should be adjusted to the listed value x 5 9 For example for 9 cm electrode in carbon steel set the multiplier to 0 55 Normal alloy multiplier 1 00 x 5 9 0 55 The multipliers given in the table are based on the common corrosion reactions that occur with the constituent elements of those alloys In certain environments these reactions may be different and possibly require a different multiplier In the absence of other information the multiplier may be calculated empirically by comparing corrosion rate on the electrodes determined by weight loss with the average indicated corrosion rate from the instrument over the same period The existing multiplier used on the unit is then modified by the ratio Corrosion rate by weight loss Average corrosion rate from instrument 21 Chapter 5 Maintenance INTRODUCTION Routine maintenance of the 9030 Plus is not required The instrument fuse should it need replacement is located inside a fuse holder mounted on the printed circuit board in the unit A small screwdriver can be used to remove the fuse cover after power has been removed from the instrument CAUTION The ON OFF switch located next to the fuse holder DOES NOT disconnect the fuse from AC
13. the twelve pin connector P1 located on the circuit board From top to bottom the connector pins are identified LOOP 1 LOOP 1 LOOP 2 LOOP 2 LOOP 3 LOOP 3 LOOP 4 LOOP 4 LOOP 5 LOOP 5 LOOP 6 LOOP 6 Loop 1 is closest to the corner of the board 18 9030 Plus Reference Manual A brief description of the 4 20 mA loop calibration procedure follows After pressing the key ZERO ADJ 4 20 LOOP 1 PRESS CFG TO START is displayed While monitoring the loop current with a precision milliammeter press the CONFIGURE key and use the and W keys to adjust the current in Loop 1 to 4 00 milliamperes When the loop current has been adjusted to 4 00 mA press the CONFIGURE key to end the calibration and permanently store the calibration value After pressing the key again 5 ADJ 4 20 LOOP 1 PRESS CFG TO START is displayed While monitoring the loop current with a precision milliammeter press the CONFIGURE key and use the and W keys to adjust the full scale current in Loop 1 to 20 00 milliamperes When the loop current has been adjusted to 20 00 mA press the CONFIGURE key to end the full scale calibration and permanently store the calibration value By pressing the key again the user can step through the calibrations for 4 00 mA and full scale 20 00 mA for each remaining loop Loops 2 and 3 for a single channel unit and Loops 2 3 4 5 and 6 for a two channel unit If t
14. 5 seconds after applying power to the instrument The power toggle switch S2 is on the main board inside the instrument enclosure The message SET UNITS will appear on the display To program the units respond with Y ES by pressing the key Pressing the CONFIGURE key will display ENGINEERING UNITS and the units presently selected either MPY or mmPY will be bracketed by flashing gt and lt Select the desired units with the or W keys and press CONFIGURE to store the selection The factory default is MPY After setting the ENGINEERING UNITS press the key so the temperature units can be set To set the temperature units pressing the CONFIGURE key will display TEMPERATURE UNITS and the units presently selected either Celsius or Fahrenheit will be bracketed by flashing gt and Select the desired units with the or W keys and press the CONFIGURE key to store the selection The factory default is Celsius To return to normal operation press the DISPLAY key and the 9030 PLUS will revert to normal operation If the 9030 PLUS has just been installed and connections have been made to the 4 20 mA loop outputs each loop should be calibrated at 4 00 mA and 20 00 mA to achieve maximum output accuracy To perform the initial loop calibrations press the key and the display will show ACCESS CALIBRATIONS YES UP DOWN Press the key to proceed with the loop calibrations The six 4 20 mA loops are accessible via
15. Electrochemical Current Noise ECN between the two electrodes when the electrodes are connected to a zero impedance ammeter effectively measuring the short circuit current The 9030 Plus measures this current and displays the results in units of 0 50 microamperes per square centimeter of surface area of each electrode Regular electrodes are 5 0 square centimeters and therefore one imbalance or pitting unit is 2 5 microamperes of current The purpose for this scaling is to make Chapter 4 Operation 19 the imbalance reading meaningful when compared to the corrosion rate reading in mils per year It has been found empirically that when the imbalance reading is less than the mils per year corrosion rate reading or close to zero corrosion is general corrosion with insignificant pitting If the imbalance becomes more erratic and similar to or greater than the corrosion rate value this is indicative of increased pitting If the imbalance is up to ten times greater than the corrosion rate or very erratic this is indicative of a significant pitting which should be verified by visual inspection of the probe electrodes Imbalance can be caused by several factors 1 Severe pitting Pitting is generally irregular and non uniform consequently the greater this irregularity or non uniformity the greater is the probability of imbalance between the two electrodes Pitting is generally accompanied by an increase in imbalance and also greater irregularity and fluct
16. Serial Number 9030 Plus CORRATER INSTRUMENT USER MANUAL ROHRBACK COSASCO SYSTEMS INC 11841 E Smith Avenue Santa Fe Springs CA 90670 Tel 562 949 0123 800 635 6898 Fax 562 949 3065 P N 710680 MANUAL Rev E 12 07 2002 Rohrback Cosasco Systems rights reserved CORROSOMETER and are registered trademarks of Rohrback Cosasco Systems Inc No part of this manual may be reproduced or transmitted in any form or by any means electronic or mechanical including photocopying and recording for any purpose without the express written permission of Rohrback Cosasco Systems Inc Contents Chapter 1 Introduction cena ene ce oo suene ceo nahe 1 Chapter 2 Specificat ois eoe ec tee ein ec nn o tetes tente 5 Chapter 3 ce vs nus if nn 9 Chapter en mn 15 Chapter 5 Maimf nallce xa cce senec c atentiedneensste nice 21 Chapter 6 Data Logger Function and Set Up Using Corrdata Plus 25 Appendix A Theory of Operation of CORRATER Systems 46 11 9030 Plus Reference Manual Figures and Drawings Figure Page Vel Pictote Plus QI ost deoa uero use aUa ue ek 1 3 1 Mounting and Unit Dimensions of 9030 9 3 2 Installation Wiring Connections e ea Sees Nei eue TN A 11 3
17. alid measurements of ir and corrosion rate actual time required can vary from a few seconds up to 20 minutes depending upon the metal process combination being measured Choosing too short a polarization time can result in current readings much higher than the true ico thus causing measured corrosion rate to be lower than actual sometimes by a significant amount 48 9030 Plus Reference Manual Resultont Current Profile Applied Potentiol Step Typically 10 mV Current Asymtote 5 s PC 5 VO 5 ot ot an aw IY Time minutes Figure A 2 Typical LPR Current vs Time Decay Curve Solution resistance can also have a significant effect on accuracy if it is relatively high compared to the polarization resistance In most industrial water applications conductivity of the solution is high and solution resistance is low compared to the polarization resistance so imeas is an accurate measure of polarization resistance and therefore corrosion rate A serious problem develops however when the solution resistance increases or the polarization resistance decreases enough to make the solution resistance a significant portion of the total resistance to current flow between the electrodes In these cases the accuracy of the LPR measurement is affected This situation tends to occur at high corrosion rates low polarization resistance and in solutions with low conductivity high solution resistance and is ma
18. ame type of treatment as in the plant whenever installing new material Generally use a full strength sample ofthe treatment chemical Carefully place the new electrodes into the solution for a 6 12 hour period and then thread them onto the probe and put the probe in service Some systems have an initial high level of treatment before the inhibitor rate decreases to a maintenance level The treatment relative to the probe electrodes should be considered Ifthe electrodes are installed without pretreatment the corrosion rate indicated will be that which would occur on new material put in the system This may typically take a few hours to a few days to decrease to the normal on going value Pretreatment may artificially protect the material so that it is unrepresentative of any new material that may be put in the system Correlation with Electrodes as Coupons Weigh the electrodes in the same manner as a coupon would be weighed on a balance scale graduated to 0 0001 gram before placing them in service The coupon should be placed into service at the same time After a 30 60 or 90 day period remove both clean them and analyze them in the same manner The instrument readings averaged over a period of time should correlate with the data from the electrodes and coupons 24 9030 Plus Reference Manual 25 Chapter 6 Data Logger Function and Set Up Using Corrdata Plus GENERAL The 9030 Plus has an internal data logger for each probe This
19. ation ofthe unit Each cable is ten feet long and terminated in 6 pin type B connector The type B connector is suitable for direct connection to all CORRATER probes The only exception is interconnection to a Model 6080 High Pressure CORRATER probe where a fixed probe connecting adapter is also required The cable length can be extended up to 2000 feet if desired Since the cables are internally shielded it is not recommended that extender cables be used since the internal shield is not propagated through the standard 6 pin connector Cables of any length can be ordered from the factory with the B connector on one end and the other end stripped and tinned ready for user installation to the instrument See Figure 3 2 The two probe cables are connected through weather proof glands to screw terminal connectors that plug into the circuit board mounted on the inside front cover of the instrument enclosure Using a small flat bladed screw driver the probe cables can be removed The probe cable consists of 3 twisted pairs and one ground shield The schematic diagram below depicts the wire colors and appropriate connector pin assignments The probe connector pin designations connector P3 for Probe 1 and connector P2 for Probe 2 are marked on the printed circuit board silk screen equired for Intrinsic Safety applications only
20. ck Next and setup the Group name rts Add Group X Enter a descriptive name for this group Demo The name you supply for this group will appear in all probe view outlines for this site Clicking on the finished button will create this group Cancel lt Back Next nones Click Finished Now click in the check box to the left of the Group name 1 CORRDATA Plus Demo Site Bl x File View Preferences Window Qn 9 eee Site Probe List Unit ID r Group New E dit Remove New Edit Bemove Current Site C Program Files RCS CORRDATA PLUS Demo SIT 10 10 2007 Now probe set up for data logging can proceed Click New under Probe Click Next 31 Select Corrater for technology Choose probe type from Select Model Number drop down list Add a New Probe X Add this probe to Group Demo Select a Technology Select a Model Number 51 12T 0 K03005 1 ine Einished NOTE 1 Probes with a behind the first 4 numbers indicate a temperature capable probe BE SURE that if that is the correct probe type the Temperature Capable box MUST BE CHECKED NOTE 2 If the instrument was not previously configured for temperature probes from the unit front anel edit the probe configuration t
21. ct measure units are set Create a New Site Determine the Standard Units of Measure for this Site MetalLoss mils Thickness inch Temperature Elevation The system has determined the following default values for this site You can change either one to an appropriate value Site file name Demo SIT Site file directory location Ic Program Files RCS CORRDATA PLUS yl Clicking on the Finished button will add this site to the database Cancel lt Back Next gt Erisnea Make sure the correct site is selected from the Site Name list 1 CORRDATA Plus Demo Site File View Preferences Window 1082906258544 57 Select an Existing Site Site Name CMDL Test CUST SERV Cust Site af Demo Site john ladelljones NALCO Global b E Site Probe List Graph and View Data Device Configuration Event Log Receive Data Site Reports Current Site C Program Files RCS CORRDATA PLLISSDemo SIT 10 10 2007 4 Then click Site Probe List 715 CORRDATA Plus Demo Site _ Elle View Preferences Window Help aaar Site Probe List x sUnit ID Probe Remove New Edit Remove Current Site C Program Files RCS CORRDATS PLUS Demo SIT 10 10 2007 Click New button under Group 30 9030 Plus Reference Manual Cli
22. data logger functions as a CORRDATA Remote Data Collector RDC While the data logger section is powered by the 9030 Plus it operates independently from the 9030 Plus and only records the measured values at the time interval 30 minutes minimum specified through the CORRDATA Plus Software Pressing the DATA LOG key establishes access to the data logger function When this is done the display will prompt the user to press the up arrow key to configure Probe 1 If the instrument has two probes pressing the down arrow key will configure Probe 2 Once the probe 15 selected all configuration and data gathering is performed by a computer running the CORRDATA Plus software The computer must be connected to the 9030 Plus data port using the cable supplied with the 9030 Plus IMPORTANT Please note that after pressing the DATA LOG key to perform the above function there is a one minute period in which the instrument will accept probe configuration or download data After this period the instrument returns to its normal operating condition and is unable to communicate with the computer unless the DATA LOG key is pressed again Data Logging Set Up Using CORRDATA Plus Software Please use the following step by step instructions to set up data logger operation for one or two probes For any specific information regarding details on using Corrdata Plus please refer to the Corrdata Plus Software Users Manual Chapters 7 through 10 explain how to
23. e 600 Ohms NOTE This device sources current for all loops 6 process measurements assigned to 6 analog outputs Loop 1 Probe 1 Corrosion Rate Loop 2 Probe 1 Imbalance Loop 3 Probe 1 Temperature Loop 4 Probe 2 Corrosion Rate Two Channel Instruments Only Loop 5 Probe 2 Imbalance Two Channel Instruments Only Loop 6 Probe 2 Temperature Two Channel Instruments Only Control Alarm Setpoint Relay Maximum current capacity 1 Amp 230 VAC resistive load SPDT Data Logger Isolated RS232 interface to personal computer running CORRDATA Plus Software 9030 Plus Reference Manual Chapter 3 Installation GENERAL The 9030 Plus is a field mountable instrument that is designed to be mounted on a wall bulkhead or other flat surface Mounting tabs fastened to the back panel of the instrument protrude beyond the NEMA 4X enclosure and allow mounting to a flat surface Figure 3 1 provides dimensional information for mounting the unit d EC IRE d um 165mm Rd orn ROHRBACK SYSTEMS INSTRUMENT mm mm a 7 ER Des B E Figure 3 1 Mounting and Unit Dimensions of 9030 Plus Unit 10 9030 Plus Reference Manual Power Th
24. e ON OFF switch for the unit is inside the NEMA enclosure mounted on the printed circuit board near the front of the instrument The fuse holder standing vertically next to the ON OFF toggle switch contains a T500 milliamp 250 volt 5X20mm fuse RCS replacement PN 098003 13 NOTE Fuse must be replaced with the exact type in the unit to maintain CE compliance The instrument is supplied with an 8 foot power cable which is terminated with a standard three prong plug for 115 volt operation or stripped and tinned conductors with standard IEC color code LIVE brown NEUTRAL blue GROUND green yellow for 230 volt operations CAUTION The power supply voltage must correspond to that selected by the slide switch located inside the unit The switch is clearly marked and should be properly set at the factory WARNING To protect operating personnel it is necessary that the instrument be grounded To accomplish this the offset round prong on the furnished power plug must be connected to the facility ground In addition to this when wiring the setpoint relay 4 20mA loops or probe cables it is recommended that power be completely removed from the instrument Even if the ON OFF switch is in the OFF position the AC mains are still connected to some circuitry within the unit and represent a shock hazard Damage to the unit could also occur if operating personnel accidentally touch high voltage circuits with tools during initial wiring setup Chapter 3
25. e compared to other major LPR probes because they utilize a closely spaced electrode Figure 4 Rohrback Cosasco 3 Electrode Probe Configuration A better way to deal with this problem however is to directly measure and compensate for the solution resistance Rohrback Cosasco has exclusive patent rights to the Solution Resistance Compensation SRC technique incorporated in most of the CORRATER range of instruments In this method a high frequency a c voltage signal is applied between the electrodes short circuiting R through the double layer capacitance thereby directly measuring the solution resistance The state of the art patented SRC technology also eliminates the need for a third electrode even in low conductivity solutions Consequently Rohrback Cosasco s two electrode probes have become the standard RCS offering with the three electrode probe available on special order only Appendix A 51 The above points are clearly indicated in ASTM Standard Guide G96 which quotes 3 2 8 Two electrode probes and three electrode probes with the reference electrode equidistant from the test and auxiliary electrode do not correct for effects of solution resistance without special electronic solution resistance compensation With high to moderate conduc
26. e in many element and alloy materials The material selected should closely match the material of construction ofthe pipe or vessel for which corrosion information is desired Probes should be installed where corrosion is most likely to be greatest so that readings will truly represent the most aggressive system corrosion rates Preferably they should be located where the liquid flow velocity past the electrode exceeds 1 foot per second 0 3 m sec if it is required to measure corrosion rates representative of a flowing environment Alignment of the electrodes relative to the direction of process flow is important to obtain reliable corrosion rate measurements Proper alignment is with the imaginary line connecting the center lines of the two electrodes perpendicular to the direction of the process flow Refer to Figure 3 3 With this orientation one electrode does not shade the other electrode and both are subject to nearly the same corrosive environment If a probe is installed in an elbow fitting where flow changes direction position the probe so that the electrodes face the oncoming flow Refer to Figure 3 4 Flow Flow he Recommended Not Recommended ZI AN ASS N N N Figure 3 3 Probe Orientation Relative Figure 3 4 Probe Orientation at to Flow a Tee Fitting Chapter 3 Installation 13 Probe Connection The 9030 Plus is supplied with either one or two probe cables dependent on the configur
27. ependent data logger function for each probe operates with CORRDATA Plus Software through isolated RS232 interface from personal computer 1023 readings per channel 511 readings for temperature capable CAT probe Minimum time between readings with logger is 30 minutes ENVIRONMENTAL Instrument Operating Temperature 32 F 122 F 0 50 Storage temperature 4 F to 131 F 20 C to 55 Enclosure One circuit card housed in a 6 x 6 x 4 inch NEMA enclosure Mechanical Size See Figure 3 1 Unit Weight 6 Lbs Probe to Instrument Cable Length Without Barrier 2000 feet 610 m maximum With Barrier 1300 feet 396 m maximum Barrier type Compatibility MTL 755 and 761 See Figure 3 5 Display Vacuum Fluorescent Technology Blue Chapter 2 Specifications 7 INTERFACE Probe 10 foot integral probe cable with type B connector compatible with all CORRATER probes and type C or type probe connecting adapters for MODEL 6080 high pressure probes Power Requirements Switch selectable 115 or 230 volt operation 47 63 Hz factory set as specified by user Instrument power consumption is 15 watts nominal 105 125 VAC or210 250 VAC 8 foot power cable with stripped and tinned conductors with standard IEC color code Isolated Analog Outputs Six 4 20 mA current drivers which can be calibrated at the 4 and 20 mA endpoints Maximum load resistanc
28. ew Preferences Window Help Qn ease eee ite Probe List L Group Group New Edit Remove E Remove Current Site C Program Files RCS CORRDATA PLUS Demo SIT 10 10 2007 z Now Corrdata Plus has the setup for the 9030 Probe 1 stored in its database 35 For units with 2 probes repeat the above steps Click a check mark next to Demo under Group File View Preferences Window Help Fi E Aa 24 v RRIEK Description Unit ID 9030 Plus Probe 1 Demo Location Group New E dit Remove Current Site C Program Files RCS CORRDATA PLUS Demo SIT 10 10 2007 Then under Probe select New and repeat the steps used for Probe 1 for the addition of Probe 2 However when arriving at the Select Collection Device screen set up as follows Select the Collection Device LY lt Back gt Finished 36 9030 Plus Reference Manual Keep going until arriving at the following screen then fill in the tag as 2 Add New Probe X Unit ID 2 Technology CORRATER Enter Unit Tag ID Enter Date Installed fi 0 10 2007 1 26 56 PM Enter Probe Notes Then click Next and Finished Add a New Probe X Unit ID 2 Unit Tag ID 2 Group Demo Device 9030 Plus Probe 2 Clicking on the Finished button wi
29. gram the desired selection The unit is now back in the Configure selection mode Use the arrow keys to scroll to edit another parameter or press DISPLAY to return to the display mode and V Keys These keys are used to scroll through the parameters list They are also used in conjunction with the CONFIGURE key to edit specific selections and or parameter values 16 9030 Plus Reference Manual Initial setup requires the operator to choose various parameters specific to the process being measured Becoming familiar with the following parameter list will identify which parameters can be changed and provide information about the instrument s capabilities Parameter List The parameter lists all have a similar format The top line displays what parameter will be edited and for probe specific parameters what probe is selected The second line is the selection parameter value which can be changed with the and W keys A brief description of the parameter list follows Global Parameters ENGINEERING UNITS The corrosion rate measurement units are either mils per year MPY or millimeters per year mmPY The factory default is MPY TEMPERATURE UNITS The temperature measurement units are either degrees Fahrenheit or Celsius The factory default is Celsius Probe Specific Parameters CYCLE TIME cycle time is independently set for Probe 1 and or Probe 2 Cycle Time is adjustable from 3 0 to 30 0 minutes in 0 5 minute increments
30. he user wants to reset the unit to the factory default settings press the key multiple times until RESET FACT DEFAULTS PRESS CFG TO START is displayed To reset all settings including the 4 20 mA loop calibrations to the factory defaults press the CONFIGURE key After a two second delay the unit will display RESET TO DEFAULTS COMPLETE To return to normal operation press the DISPLAY key Setting Probe Specific Parameters To set probe specific parameters in the 9030 PLUS press the CONFIGURE key ENABLE PROBE 1 YES UP NO DOWN will be displayed Press the key and SETUP PROBE 1 YES UP NO DOWN will be displayed Press the key and PR 1 TYPE will be displayed along with the current selection To select and set a Probe Specific Parameter press CONFIGURE and the selected parameter will be bracketed by flashing gt and To set the displayed parameter press the CONFIGURE key To select and set a different parameter use the and W keys to select the parameter and the CONFIGURE key to set the parameter Each of the Probe Specific Parameters can be selected and set by using the and W keys and following the procedure in the paragraph above i e CONFIGURE select parameter CONFIGURE revert to normal instrument operation press the DISPLAY key Interpretation of Operating Parameters and Readings Imbalance Readings Imbalance is often referred to as pitting tendency It is actually a sample of
31. hows that the result is a resistance the Polarization Resistance Rp While strictly speaking there are both anodic and cathodic R values which can differ they are usually assumed to be equal The resistance to current flow between anode and cathode on the LPR probe is the sum of both polarization resistance values and the resistance of the solution between the electrodes Rs as shown in Equation 2 meas From Equations 1 and 2 obtaining results from the LPR technique would seem to require only instantaneous readings of resistance In practice however the determination of polarization resistance is 47 complicated a capacitance effect at the metal fluid interface double layer capacitance Figure A 1 15 an equivalent electrical circuit of the corrosion cell formed by the measuring electrodes and the fluid showing the importance of Rs and double layer capacitance effects Test Auxiliary Electrode Electrode Reference Electrode where used Figure 1 Equivalent Circuit of LPR Probe The effect of the double layer capacitance is to require the direct current flow to initially charge up the capacitors resulting in a decaying exponential current flow curve vs time after application of the polarizing potential difference A typical LPR current vs time curve is shown in Figure A 2 Each metal fluid interface has its own characteristic capacitance which in turn determines the amount of time required to obtain v
32. l a MANF My Do 8 IE GO 213PM After that the following screen should appear Corrdata Plus X 1 9030 Plus Probe 1 Configuration is complete Then click Close on the next 2 screens 40 9030 Plus Reference Manual FOR 2 PROBE UNITS If the unit is a 2 probe unit repeat the steps used for Probe 1 but under Select Method select 9030 Plus Probe 2 and click a blue check mark in the left hand box as shown below 155 CORRDATA Plus Demo Site ruf File View Preferences Window Help Se 950 es 2 19 E x Select Device Configure Device C RDC Select Method 030 Plus Probe 2 Close 9030 Plus Select a Complete Group or an Individual Probe from the list below clicking in the first column 9030 Plus Probe 1 Demo Location 3030 Plus Probe 2 Demo Location Configuring an RCS 9030 Plus Probe 2 10 10 2007 Z Now press the Data Log key on the front of the 9030 press the Down arrow on the front of the unit to select Probe 2 then click Configure Device The 9030 will display COMMUNICATING PLEASE WAIT You may see the following screen if the Probe 2 was configured differently Cordata Plus Device Configuration X RDC is already configured Click to proceed to halt operation Click to have the unit accept the new config
33. lectrical current A CORRATER instrument determines the corrosion rate by measuring the current from a small applied potential difference between the two electrodes The 9030 Plus extends the practical solution resistance range for LPR measurements It measures the electrochemical impedance by use of a patented AC technique which automatically compensates for the solution resistance between the corrosion measuring electrodes It does this without resorting to a third electrode or correction curves The 9030 Plus is however compatible with all two or three electrode probes already in use A discussion of the LPR method of corrosion rate measurement is presented in Appendix A of this manual The 9030 Plus performs temperature measurements when reading suitable CORRATER probes These probes measure temperature with a platinum resistance temperature device RTD located inside the probe near the process end By measuring the RTD resistance the 9030 Plus can calculate and display the water temperature present at the probe location The 9030 Plus is designed for the convenience of the user Automatic solution resistance compensation improves the utility convenience and accuracy of corrosion rate measurements The 9030 Plus also monitors a form of Electrochemical Current Noise ECN between the electrodes called imbalance or pitting tendency This is a qualitative and very useful indication of instability in the material surface co
34. ll add this probe to the current site Now the following screen should appear 37 1 CORRDATA Plus Demo Site File View Preferences Window Help IUS 9030 Plus Probe 1 Demo Location 9030 Plus Probe 2 Demo Location New Edit me Bemove Current Site C Program Files RCS CORRDATA PLUS Demo SIT 10 10 2007 A Now the database is set up for 2 probes Now proceed to configure data logging for the 9030 Plus using Corrdata Plus Move the mouse to the computer icon under Help in the title bar You should see the following CORRDATA Plus Demo Site B x File View Preferences Window Help EE Site Probe List 9030 Plus Probe 1 Demo Location 9030 Plus Probe 2 Demo Location New E dit Remove B Bemove Current Site C Program Files RCS CORRDATA PLUS Demo SIT 10 10 2007 Z Click on the icon and you should see the following 38 9030 Plus Reference Manual 1 CORRDATA Plus Demo Site B x 909 880425854 7 Select Device Mate Configure Dey C RDC 9030 Plus Select Method Select a Complete Group or an Individual Probe from the list below by clicking in the first column L Group Description Unt Location 10 10 2007 2 Under Select Device click the 9030 Plus radio button select 9030 Plus Probe 1 in the
35. nifested by the indicated measured corrosion rate being lower than the actual corrosion rate The graph in Figure A 3 shows the effect ofthis limitation on the recommended operating range of LPR instruments Appendix 49 J8 D 5 E uyup Ayyonb Buioo2 Joak Jed J094 sad ww 15 uoquo 8304 40150240 Conductivity umhos cm robe with high frequency for solution resistance p n ve DO On 42 o0 NO 1 E 29 Oo 586 5 99 0 30 of nos 9556 o v s 2 3 9 o ius Q0 ce SOO ges t a 5 o o o N o 9 3 2 Figure 3 Operating Range of LPR Instruments Corrosion Rate vs Solution Conductivity 50 9030 Plus Reference Manual Several techniques have been used over the years to minimize the impact of solution resistance on LPR measurements The most common techniques involved the use of a three electrode probe The effectiveness of the reference electrode in reducing the effect of solution resistance has been shown to be dependent upon the proximity ofthe reference electrode to the measurement electrode Rohrback Cosasco three electrode probes see Figure 4 are uniqu
36. nsistent with pitting or localized corrosion A total of six 4 20 mA current loop drivers are provided to remotely monitor the corrosion rate imbalance and temperature measurements For convenience the loops are designated as follows These six electrically isolated 4 20 mA current sourcing loop outputs provide convenient connection s to other recording and computing devices For local monitoring a vacuum fluorescent display makes it easy to read the measured data or change initial setup parameters An internal relay with programmable set points for both corrosion rate and imbalance is available for external alarm or control circuit connection 3 After installation the operator only needs to perform an initial setup to set the cycle time if other than automatic probe multiplier or other parameters of interest Initial setup is performed via four front panel keys while monitoring the display The operation section of this manual contains a description of user definable parameters In some cases initial setup may not be required since factory defaults have been set A weatherproof NEMA 4X enclosure houses the instrument Four mounting tabs on the rear corners of the instrument enclosure provide permanent mounting All probe cables exit at the bottom of the instrument The unit includes one or two standard 10 foot probe cables and an AC line cord Cables for the 4 20 mA loops and the setpoint relay can be fabricated for specific in
37. nts are not practical because the areas are small Instead current flow between the two metallurgically identical electrodes ofa CORRATER probe under short circuit conditions can be used to indicate pitting tendency Rohrback Cosasco CORRATER instruments include a imbalance pitting reading The user should note that this is a qualitative measurement or index and utilize it accordingly It has proven very useful in many applications e g cooling water treatment and offers information not generally available about a system except by coupons which lag behind actual events and offer no way of detecting upsets If the pitting reading is low compared to the corrosion reading the pitting problem will probably be minimal On the other hand a pitting reading which is high compared to the corrosion reading can indicate that pitting or crevice corrosion will be the main form of corrosive attack When the readings are about equal some pitting is indicated but the pits will probably be broad and shallow
38. o CORROTEMP CORRATER using the front panel switches Select the correct metallurgy type from the drop down list Add a New Probe X Select a Probe Type Standard Select an Alloy Cancel lt Back gt Einished Click Next 32 9030 Plus Reference Manual If the unit has one probe only select 9030 Plus Probe 1 from the drop down list Add a New Probe X Select the Collection Device Enter location of probe if desired Demo Location Add a New Probe X Enter Location of Probe emo Location GPS Coordinates Latitude 90 0000000 Longitude 180 0 0000000 Elevation 00 ft Cancel Back ine Finished 33 Enter the reading interval Note Even though the 9030 can read in a minimum of 3 minutes the minimum reading interval for data logging is 30 minutes Add a New Probe X Unit ID 1 Technology CORRATER Enter Unit Tag ID Cee Enter Date Installed fi 0 8 2007 7 20 56 Enter Probe Notes Cancel lt Back Finished Then click Next 34 9030 Plus Reference Manual Unit ID 1 Unit Tag ID 1 Group Demo Device 9030 Plus Probe 1 Clicking on the Finished button will add this probe to the current site After clicking Finished the following screen should appear 1 CORRDATA Plus Demo Site in x File Vi
39. ode Replacement As supplied from the factory CORRATER electrodes have grit blasted surfaces and require no further cleaning before they are used Probes should be checked at intervals particularly for conductive debris shorting out the electrodes which may be indicated by a very high corrosion rate reading They should be cleaned and polished to a dull shine with an emery cloth After cleaning the electrodes should be 22 9030 Plus Reference Manual thoroughly degreased in a suitable solvent and handled with a clean cloth or paper towel to prevent contamination The important factor is that the electrodes should be REPRESENTATIVE of the conditions to be monitored New electrodes may be more responsive to changes in the corrosivity of the fluid Electrodes which have been in use for some time will be more representative of corrosion rates on the more aged plant material which will have some film build up Table 5 1 CORRATER MULTIPLIER FACTORS NOTE These factors are recommended for use with the 9030 Plus instruments when setting the MULTIPLIER value as described in Section 4 They are based upon use of CORRATER electrodes which have surface areas of 5cm for standard probes and 0 5 cm for flush probes K03005 Pipe Grade Carbon Steel 491100 Aluminum 1100 0 92024 Aluminum 2024 C11000 Copper 110 ETP Comm Pure C44300 CDA 443 Arsenical Admiralty C44500 CDA 445 Phosphorized Adm E C64200 CDA 642 1 Silicon Bronze C68700
40. power Ifa visual inspection or an electrical resistance check of the fuse confirms it is open replace it with a T500 milliamp 250 volt 5X20mm fuse RCS replacement PN 098003 13 NOTE Replace fuse with the exact type originally in the unit to maintain CE compliance Probes however should be inspected at intervals and electrodes replaced when required Ifa problem is suspected with the 9030 Plus instrument the following tests can be performed to verify proper operation of the instrument Instrument and Probe Cable Test The instrument is shipped from the factory with CORROTEMP test probes RCS part number 710617 These test probes have a nominal 5 MPY corrosion rate and a 100 C temperature RTD value simulated by the probe Ifthe test probes give acceptable readings then any problems are likely caused by the process itself or the probe s in service A fouling problem for example can bridge the electrodes and give readings outside the normal instrument measurement range NOTE Be sure to set the multiplier parameter s to 1 0 when measuring the test probe s and reset the multiplier factor s to the previous settings 1f necessary before returning to normal operation Probe Replacement Probe replacement is not required except due to damage or deterioration Replace the probe if there is physical damage or a low resistance less than 1 Meg Ohm between the electrodes when disconnected from the electronics Probe Cleaning and Electr
41. ress the Data Log key then press Up arrow Probe 1 Then click Read From Device The 9030 will display COMMUNICATING PLEASE WAIT The computer should display the following 715 CORRDATA Plus Demo Site 10 x File View Preferences Window Quou29060 85 44 amp 7 Select Device C Mate 9030Plus C Manual Entry Select Method 3030 Plus Probe 1 Receive Data To Group Demo Sending PC Ready 10 11 2007 Then Corrdata Plus X 1 9030 Plus Probe 1 Data reception complete Click You should now see the following screen 43 115 CORRDATA Plus Demo Site O x File View Preferences Window Help MF Kaz ly 2 E This list below represents batch data which has been received from the device Please select an action to Receive Data Manager perform for each of the items requiring review Merged Data _ Group Unit Readina Last Recorded Status Accept All 0 1 Clean data Reject All Accept Batch Reject Batch View Batch 10 11 2007 z Click View Batch to view the data collected 1 CORRDATA Plus Demo Site File View Preferences Window Help 907 View Received Data for Batch ID 0 Unit ID 1 X Received Header Tag fi Interval a0 Mult fi Type m Detail Records lol x
42. sh This setpoint can be turned Chapter 4 Operation 17 OFF or it can be programmed from 0 01 MPY to 1000 MPY or the metric equivalent values The factory default setting is OFF PROBE IMBALANCE SETPOINT Ifthe measured imbalance on a channel exceeds the programmed setpoint it causes the setpoint relay to close and the displayed imbalance reading to flash This parameter can be turned OFFor it can be programmed from 0 01 IU Imbalance Units to 1000 IU or the metric equivalent values The factory default setting is OFF 4 20 LOOP OUTPUTS The 9030 PLUS has the capability to make up to six process measurements A single channel unit can measure Probe 1 Corrosion Rate Probe 1 Imbalance and Probe 1 Temperature A two channel unit will make the same three measurements for each ofthe two measurement channels The following are the 4 20 mA loop output assignments Loop 1 Probe 1 Corrosion Rate Loop 4 Probe 2 Corrosion Rate Loop 2 Probe 1 Imbalance Loop 5 Probe 2 Imbalance Loop 3 Probe 1 Temperature Loop 6 Probe 2 Temperature POWER UP ACCESSIBLE PARAMETERS In addition to the Global Parameters listed above there 15 a set of function parameters that are accessible only during a brief period after power is applied These include calibration of the zero and full scale adjustments for the 4 20 mA loops and resetting the instrument to factory defaults This special calibration menu is accessed by holding down both arrow keys simultaneously for
43. stallations 9030 Plus Reference Manual Chapter 2 Specifications OPERATIONAL Channels 1 or 2 Channels CORRATER input Probe Compatibility All two electrode CORRATER and CORROTEMP probes with either standard Or flush type electrodes The instrument is also compatible with three electrode probes Corrosion Rate Ranges Autoranging from 0 01 to 1 000 MPY Imbalance Ranges pitting index Autoranging from 0 01 to 1 000 pitting units 1 pit unit 2 5 microamperes Cycle Time Range Independent cycle time for probe channels 1 and 2 Automatic or manually adjustable 3 to 30 minutes in 1 2 minute increments Default is 5 minutes Polarization time is 25 of cycle time Multiplier Range 0 50 to 3 00 in steps of 0 01 The multiplier compensates for the differences between electrode materials electrode sizes and abnormal operating conditions Default multiplier is 1 0 mild steel Temperature Measurement Range 40 C to 260 Accuracy 2 Excluding sensor Repeatability 1 0 C Resolution 0 1 Analog Isolated Output Ranges Corrosion Rate and Imbalance 1 2 5 10 20 50 100 200 500 1000 MPY or pitting units Temperature 40 to 260 C 6 9030 Plus Reference Manual Control Alarm Setpoint Relay Independently set levels for corrosion rate and imbalance Continuously adjustable from 0 to 999 MPY Data Logger Ind
44. tched off it will not record data When the unit is powered up data logging resumes A battery powered Real Time Clock RTC inside the unit provides the time and date stamp at each process measurement interval Initial Setup NOTE If using the Data Logging function please see instructions in Chapter 6 on setting up data logging using Corrdata Plus first This will help prevent header conflicts and erroneous data when uploading from the 9030 Plus to Corrdata Plus Instrument operation is customized via five front panel keys A description of each key and the function it performs follows DISPLAY This key displays the measured corrosion imbalance and temperature data On two channel instruments Probe 1 data is shown on the display top line and Probe 2 data is shown on the bottom line Use this key to display current data after exiting the Configuration mode or Data Logging mode CONFIGURE This places the instrument in the configuration mode where the measurement parameters can be set or changed Use the arrow keys and W to scroll to the parameter to be configured Once the parameter to be configured is displayed press the CONFIGURE key again to enter the edit mode The value displayed will then be bracketed by gt symbols that flash ON and OFF indicating that the parameter is in the edit mode Use the arrow keys to scroll through the values until the desired value is displayed Next press the CONFIGURE key again to pro
45. tivity environments this effect of solution resistance is not normally significant 3 2 9 Three electrode probes compensate for the solution resistance R by varying degrees depending on the position and proximity of the reference electrode to the test electrode With a close spaced reference electrode the effects of can be reduced up to approximately ten fold This extends the operating range over which adequate determination of the polarization resistance can be made 3 2 10 A two electrode probe with electrochemical impedance measurement technique at high frequency short circuits the double layer capacitance Ca so that a measurement of solution resistance can be made for application as a correction This also extends the operating range over which adequate determination of polarization resistance can be made Imbalance or Pitting Index In addition to general or uniform corrosion localized corrosion pitting may occur in a system This can result in much more rapid failure of a structure than a simple measure of corrosion rate would indicate A pit on the metal surface is the result of a localized high anodic current density Positive ions flow away from the pit into the solution and electrons flow away from the pit into the surrounding metal If it were possible to place a zero impedance ammeter between the pit and the nearby metal surface the current in the anode cathode system of the pit could be measured Individual measureme
46. uation of the reading 2 Improper or inadequate inhibitor film formation Where filming inhibitors are used and are not established due to inadequate flow or quantity of inhibitor imbalance is greater and shows greater fluctuation This will often anticipate an increasing corrosion rate with reducing inhibitor film 3 Differential scaling or fouling of the electrode 4 Damage to an electrode or loosened electrode NOTE Imbalance readings will typically increase when corrosion rate values increase There should be concern for pitting when the imbalance increases significantly without a similar increase in corrosion rate Cycle Time Selection The cycle time setting when properly set allows sufficient settling time to make accurate polarization resistance measurements on the probe The chemistry of the process determines the time required for proper settling In order that measurements are not made on the slope of some curve it is better to have a cycle time greater than that required in order to provide for some margin in the event that the process shifts in direction Corrosion rate measurements on new electrodes may not be representative of corrosion in the system until the probe has been exposed to the flowing fluid for several hours up to one or two days This length of time is required to allow the electrode surfaces to stabilize or age to that similar to the material of the plant New material typically corrodes at a higher rate
47. uration Corrdata Plus Device Configuration X 1 RDC will be configured with the time from the Click The Fetching Tag Data screen will appear then the next screen should appear Corrdata Plus 1 9030 Plus Probe 2 Configuration is complete 41 Let the unit take about 3 hours to get 5 6 readings Now the unit is ready to upload data to the computer by using the steps below Click the Receive Data box in the Corrdata Plus screen 703 CORRDATA Plus Demo Site nl xj File View Preferences Window Help 927 085509 58 454 7 Select an Existing Site Site Name 2 CMDL Test CUST SERV Cust Site d af Demo Site john ladelljones NALCO Global mairana Site Probe List Graph and View Data Device Configuration Event Log Receive Data i Site Reports Current Site C Program Files RCS CORRDATA PLUS Demo SIT 10 10 2007 Set up the Receive Data screen to look like the one below 1 CORRDATA Plus Demo Site 9 x Elle View Preferences Window Help 7 ester Mate RDC S030Plus Manual Entry Read from Device Select Method Close r Receive Data To Group Demo Current Site C Program Files RCS CORRDATA PLUS Demo SIT 10 10 2007 42 9030 Plus Reference Manual For the 9030 Plus to upload data P
48. w section as described for Probe 1 Now the Graph and View Data section can be used to view the probe data in table form and or graphed for viewing and or printing 46 9030 Plus Reference Manual Appendix A Theory of Operation of CORRATER Systems systems measure the instantaneous corrosion rate of a metal in a conductive fluid using the linear polarization resistance LPR measurement technique Corrosion is an electrochemical process in which electrons are transferred between anodic and cathodic areas on the corroding metal resulting in oxidation corrosion of the metal at the anode and reduction of cations in the fluid at the cathode Sterns and Geary originally demonstrated that the application of a small polarizing potential difference AE from the corrosion potential Eco of a corroding electrode resulted in a measured current density imeas Which is related to the corrosion current density icorr by equation 1 b b me 2 303i b b 1 corr where ba Anodic Tafel Slope b Cathodic Tafel Slope Since the Tafel coefficients are more or less constant for a given metal fluid combination imeas 1S proportional to icorr which is proportional to the corrosion rate Equation 1 and the entire LPR technique are only valid when the polarizing potential difference is very low typically up to 20 mV In this region the curves are linear hence the term LPR Inspection of Equation 1 s
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