Emerson Model 398R Retractable pH/ORP Sensor Instruction Manual

Instruction Sheet PN 51A-398R/rev.H January 2011 Model 398R Retractable pH/ORP Sensor For additional information, please visit our website at www.emersonprocess.com/raihome/liquid/. SPECIFICATIONS MODEL 398R Measurements and Ranges pH: 0-14; ORP: -1500 to 1500 mV* Available pH ACCUGLASS Types GPHT hemi bulb or GPLR flat bulb Wetted Materials Titanium, Tefzel® , glass, choice of Kalrez® , Viton® , or EPDM (platinum: ORP only) Process Connection None, use 1 inch process connector or ball valve kit (1-1/2 inch or 1-1/4 inch — sold separately) Temperature Range 0 to 100°C (32 to 212°F) Pressure Range - Hemi bulb 100 to 1825 kPa (abs) (0 to 250 psig) Pressure Range - Flat bulb 100 to 790 kPa (abs) (0 to 100 psig) Maximum Pressure at Retraction or Insertion Code 21: 542 kPa (abs) (64 psig) Code 25: 343 kPa (abs) (35 psig) Minimum Conductivity 75 µS/cm, nominal Preamplifier Options Remote 1 *PERCENT LINEARITY FOR MODEL 398RVP pH range GPHT Hemi bulb GPLR Flat bulb 0-2 94% 93% 2-12 99% 98% 12-13 97% 95% 13-14 92% — ATEX DIRECTIVE Special Conditions for safe use 1. All pH/ORP sensors have a plastic enclosure which must only be cleaned with a damp cloth to avoid the danger due to a build up of an electrostatic charge. 2. All pH/ORP sensor Models are intended to be in contact with the process fluid and may not meet the 500V r.m.s. a.c. test to earth. This must be taken into consideration at installation. 1 1 WARNING Retractable sensors must not be inserted nor retracted when process pressures are in excess of 64 psig (542kPa) for option 21 or 35 psig (343 kPa) for option 25. WARNING System pressure may cause the sensor to blow out with great force unless care is taken during removal. Allow sufficient room for safe retraction and insertion of the sensor. Personnel should have room for stable footing while performing removal or insertion of the sensor. CAUTION SENSOR/PROCESS APPLICATION COMPATIBILITY The wetted sensor materials may not be compatible with process composition and operating conditions. Application compatibility is entirely the responsibility of the user. STORAGE ELECTRODE PREPARATION 1. It is recommended that electrodes be stored in their original shipping containers until needed. 2. Do not store at temperatures below -5°C (23°F). 3. Electrodes should be stored with a protective cap containing KCl solution (PN 9210342). 4. For overnight storage, immerse the sensor in tap water or 4 pH buffer solution. 5. A pH glass electrode does have a limited shelf life of one year. 1. Remove electrode from shipping container. 2. Remove the protective boot covering the electrode bulb. 3. Rinse away salt film with clean water, then gently shake the electrode so that the internal solution fills the bulb, thus removing any air trapped there. 1 Tefzel, Viton and Kalrez are registered trademarks of DuPont Performance Elastomers. CAUTION The buffer in the protective boot may cause skin or eye irritation INSTALLATION MAINTENANCE FOR pH ELECTRODES For sensor dimensions, see Figures 1 and 2. For sensor orientation and installation, see Figures 3 - 5. For wiring, see Figures 6 - 32. Electrodes should respond rapidly. Sluggishness, offsets, and erratic readings are indicators that the electrodes may need cleaning or replacement. pH SENSOR CALIBRATION AND MAINTENANCE TWO POINT pH BUFFER CALIBRATION Select two stable buffer solutions, preferably pH 4.0 and 10.0 (pH buffers other than pH 4.0 and pH 10.0 can be used as long as the pH values are at least two pH units apart). NOTE A pH 7 buffer solution reads a mV value of approx. zero, and pH buffers read approximately ± 59.1 mV for each pH unit above or below pH 7. Check the pH buffer manufacturer specifications for millivolt values at various temperatures since it may affect the actual value of the buffer solution mV/pH value. 1. Immerse sensor in the first buffer solution. Allow sensor to equilibrate to the buffer temperature (to avoid errors due to temperature differences between the buffer solution and sensor temperature) and wait for reading to stabilize. Value of buffer can now be acknowledged by analyzer/transmitter. 2. Once the first buffer has been acknowledged by the analyzer/transmitter, rinse the buffer solution off of the sensor with distilled or deionized water. 3. Repeat steps 1 and 2 using the second buffer solution. 4. The theoretical slope value, according to the Nernst equation for calculating pH, is approximately 59.17 mV/pH. Over time the sensor will age, both in the process and in storage, and will result in reduced slope values. To ensure accurate readings, it is recommended that the electrode be replaced when the slope value falls below 47 to 49 mV/pH. RECOMMENDED pH SENSOR STANDARDIZATION For maximum accuracy, the sensor can be standardized on-line or with a process grab sample after a buffer calibration has been performed and the sensor has been conditioned to the process. Standardization accounts for the sensor junction potential and other interferences. Standardization will not change the sensor’s slope but will simply adjust the analyzer’s reading to match that of the known process pH. 2 1. To remove oil deposit, clean the electrode with a mild non-abrasive detergent. 2. To remove scale deposits, soak electrodes for 30 to 60 minutes in a 5% hydrochloric acid solution. 3. Temperature effect on life expectancy: If glass electrode life expectancy is 100% @ 25°C (77°F), then it will be approximately 25% @ 80°C (176°F). ORP SENSOR CALIBRATION AND MAINTENANCE CALIBRATION 1. After making an electrical connection between the sensor and the instrument, obtain a standard solution of saturated quinhydrone. This can also be made quite simply by adding a few crystals of quinhydrone to either pH 4 or pH 7 buffer. Quinhydrone is only slightly soluble, therefore only a few crystals will be required. 2. Immerse the sensor in the standard solution. Allow 1-2 minutes for the ORP sensor to stabilize. 3. Adjust the standardize control of the instrument to the solution value shown in the table below. The resulting potentials, measured with a clean platinum electrode and saturated KCl/AgCl reference electrode, should be within +/- 20 millivolts of the value shown in the table below. Solution temperature must be noted to ensure accurate interpretation of results. The ORP value of saturated quinhydrone solution is not stable over long periods of time. Therefore, these standards should be made up fresh each time they are used. 4. Remove the sensor from the buffer, rinse, and install in the process. ORP of Saturated Quinhydrone Solution (millivolts) pH 4 Solution pH 7 Solution Temp °C 20 25 30 20 25 30 mV Potential 268 264 260 94 87 80 MAINTENANCE FOR ORP ELECTRODES Electrodes should respond rapidly. Sluggishness, offsets, and erratic readings are indicators that the electrodes may need cleaning or replacement. 1. To remove oil deposit, clean the electrode with a mild non-abrasive detergent. 2. To remove scale deposits, soak electrodes for 30 to 60 minutes in a 5% hydrochloric acid solution. 3. ORP (metallic) electrodes should be polished with moistened baking soda. INCH MILLIMETER NOTE: ADD FIVE (5) INCHES TO DIMENSION A IF MOUNTING A SENSOR HEAD JUNCTION BOX ONTO THE SENSOR. FIGURE 1. Dimensional Drawing: Model 398R with Optional Ball Valve PN 23240-00 INCH MILLIMETER FIGURE 2. Dimensional Warning Label and Sensor Diagram 3 FIGURE 3. Exploded View of Ball Valve Kit PN 23240-00 used with process connector PN 23166-00 (or PN 23166-01) [Ball Valve Kit includes 1-1/2 in. x 1 in. reducer, 1-1/2 in. close nipple, and 1-1/2 in. ball valve] FIGURE 4. Exploded View of Ball Valve Kit PN 23765-00 JUNCTION BOX IS OPTIONAL FIGURE 5. Mounting Details - Retraction Version 4 Wire Configuration for Code -60 and Standard Cable Options DWG. NO. 40005428 REV. A Wire Configuration for Code -61 and -62 Cable Options FIGURE 7. Wiring Sensor Model 398R-54-62 to Analyzer Models 54 and 54e. FIGURE 6. Wire Configurations Note: Sensor Model 398R-54 can be wired as shown above, but customer must prepare the BNC as shown in Figure 27. NOTES: 1. PLACE 54pH/ORP LOCATION SWITCH TO SENSOR JUNCTION BOX POSITION. 2. SEE FIGURE 30 FOR PREPARATION INSTRUCTIONS FOR CABLE PN 9200273. 3. JUMPER BETWEEN TB1-7 AND TB1-8 SUPPLIED BY CUSTOMER. 4. ADDITIONAL CABLE PREP REQUIRED FOR MODEL 398R-54. DWG. NO. 40005427 REV. A Figure 8. Wiring Details for Sensor Model 398R-54-62 Through Remote Junction Box PN 23555-00 or Through Sensor-Mounted Junction Box PN 23709-00 to Analyzer Models 54 and 54e. Note: Sensor Model 398R-54 can also be wired as shown above, but customer must prepare the BNC as shown in Figure 27. For preparing wires on end of extension cable, use Figure 29. 5 FIGURE 9. Wiring Details for Sensor Model 398R-54-62 to Analyzer/Transmitter Model 81. FIGURE 10. Wiring Details for Sensor Model 398R-54-62 to Analyzer/Transmitter Models 3081, 4081, and 5081. Note: Sensor Model 398R-54 can be wired as shown above, but customer must prepare the BNC as in Figure 27. Note: Sensor Model 398R-54 can be wired as shown above, but customer must prepare the BNC as in Figure 27. FIGURE 11. Wiring Details for Sensor Model 398R-5462 Through Remote Junction Box PN 23555-00 or Model 398R-54-61 Through Sensor-Mounted Junction Box PN 23709-00 to Analyzer Model 81. Note: Sensor Model 398R-54 can also be wired as shown above, but customer must prepare the BNC as shown in Figure 27. For preparing wires on end of extension cable, use Figure 29. 6 FIGURE 12. Wiring Details for Sensor Model 398R-54-62 Through Remote Junction Box PN 23555-00 or Model 398R-54-61 Through SensorMounted Junction Box PN 23709-00 to Analyzer Models 3081, 4081, and 5081. Note: Sensor Model 398R-54 or 398R-54-60 can also be wired as shown above, but customer must prepare the BNC as shown in Figure 27. For preparing wires on end of extension cable, use Figure 29. FIGURE 13. Wiring Details for Sensor Model 398R-50-62 or 398R-54-62 to Transmitter Model 1181. Note: Sensor Model 398R-50 or 398R-54 can also be wired as shown above, but customer must prepare BNC as shown in Figure 27. FIGURE 14. Wiring Details for Sensor Model 398R-50 Through Remote Junction Box PN 23309-03 to Transmitter Model 1181 (also for Models 1050, 1060, 1003, and 1023) 7 FIGURE 15. Wiring Details for Sensor Model 398R-50-60 Through Sensor-Mounted Junction Box PN 23707-00 to Transmitter Model 1181 (also for Model s 1050, 1060, 1003, 1023). FIGURE 16. Wiring Details for Sensor Model 398R-54 to Analyzer Models 1054A, 1054B, and 2054. 8 FIGURE 17. Wiring Details for Sensor Model 398R-54 Through Remote Junction Box 23309-03 to Analyzer Models 1054A, 1054B, and 2054. FIGURE 18. Wiring Details for Sensor Model 398R-54-60 Through Sensor-Mounted Junction Box PN 23708-01 to Analyzer Models 1054A, 1054B, and 2054. 9 FIGURE 19. Wiring Details for Sensor Model 398R-54-62 to Transmitter Model 2081. Note: Sensor Model 398R-54 can also be wired as shown above, but customer must prepare BNC as shown in Figure 27. FIGURE 20. Wiring Details for Sensor Model 398R-54 Through Remote Junction Box PN 23309-03 to Transmitter Model 2081. 10 FIGURE 21. Wiring Details for Sensor Model 398R-54-60 Through Sensor-Mounted Junction Box PN 23708-01 to Transmitter Model 2081. FIGURE 22. Wiring Details for Sensor Model 398R-54-62 to Analyzer Model 1054. Note: Sensor Model 398R-54 can also be wired as shown above, but customer must prepare BNC as shown in Figure 27. 11 FIGURE 23. Wiring Details for Sensor Model 398R-54 Through Remote Junction Box PN 23309-03 to Analyzer Model 1054. FIGURE 24. Wiring Details for Sensor Model 398R-54-60 Through Remote Junction Box PN 23708-01 to Analyzer Model 1054. 12 FIGURE 25. Wiring Sensor Model 398R-54-62 to Analyzer Model 2700. Note: Sensor Model 398R-54 can also be wired as shown above, but customer must prepare BNC as shown in Figure 27. FIGURE 26. Wiring Sensor Model 398R-54-62 to Analyzer Model SoluComp. Note: Sensor Model 398R-54 can also be wired as shown above, but customer must prepare BNC as shown in Figure 27. FIGURE 27. BNC Preparation Instructions 13 FIGURE 28. Wiring to Model 1055-01-10-22-32 FIGURE 29. Wiring Model 398R-54-61 to Model Xmt 14 FIGURE 30. Wiring Model 398R-54-62 to Model Xmt FIGURE 31. Extension Cable Preparation FIGURE 32. Model 1056 wiring diagram 15 RETRACTION CAUTION WARNING WARNING System pressure may cause the sensor to blow out with great force unless care is taken during removal. Make sure the following steps are adhered to. Failure to withdraw the sensor completely may result in damage to the sensor when the valve is closed. 4. A. Model 398R-21 (21” tube) 1. Be certain system pressure at the sensor is below 64 psig (542 kPa) before proceeding with the retraction. It is also recommended that the personnel wear a face shield and have a stable footing. Push in on the sensor end or the top of the J-box and slowly loosen the hex nut (B) of the process end male connector (A). B. Model 398R-25 (36” tube) 2. Be certain that pressure at the sensor is below 35 psig (343 KPa) before proceeding with the retraction. It is also recommended that the personnel wear a face shield and have a stable footing. Push in on the sensor end or the top of the J-box and slowly loosen the hex nut (B) of the process end male connector (A). WARNING Before removing the sensor from the ball valve, be absolutely certain that the ball valve is fully closed. Leakage from the male connector threads may indicate that the male connector is still under pressure. Leakage through a partially open valve could be hazardous, however with the ball valve closed, some residual process fluid may leak from the connector's pipe threads. 5. CAUTION If the male connector leaks during insertion or retraction, replace the O-ring (PN 9550099) in the male connector A. When the hex nut is loose enough, slowly ease the sensor back completely until the retraction stop collar is reached. The right people, the right answers, right now. The Male Connector Body (A) may now be completely unthreaded from the reducing coupling and the sensor removed for servicing. CAUTION Do not remove nut at this time. 3. Close the ball valve slowly. If there is resistance, the valve may be hitting the sensor. Double check that the sensor has been retracted to the retraction stop collar. ON-LINE ORDERING NOW AVAILABLE ON OUR WEB SITE http://www.raihome.com Specifications subject to change without notice. 8 Credit Cards for U.S. Purchases Only. Emerson Process Management 2400 Barranca Parkway Irvine, CA 92606 USA Tel: (949) 757-8500 Fax: (949) 474-7250 http://www.raihome.com © Rosemount Analytical Inc. 2011