Most of the Conductivity/Resistivity electrodes used with the 2850 can be installed into standard 3 /4 in. (NPT or ISO 7-R 3 /4) fittings.

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1 InLine Installation Most of the Conductivity/Resistivity electrodes used with the 850 can be installed into standard /4 in. (NPT or ISO 7R /4) fittings. The 8505X models are designed for integral systems, where the electronics are attached directly to the sensor. Tank Installation While the 8505X and 8506X electronics cannot be submerged, either model will accommodate tank installation. Select any electrode with a 5 m (5 ft) cable. The cable may be cut to length, but it CANNOT BE EXTENDED. The universal adapter included with 8506X models can be attached to the top of a tank or mounted to a surface near the tank. Adapt the 8505X models to tank installations by attaching a clamp to the conduit. The preferred installation for inline applications directs fl ow straight into the electrode. This confi guration reduces the probability of entrapped air bubbles, and provides the best continuous sampling of the fl uid content. If the electrode is mounted vertically in a tee, do not recess the electrode orifi ces inside the tee. Mounting upside down may help prevent air entrapment. An oversized tee or fl ow cell may be helpful for inline installations. At least 4 threads (ANSI B.0.) must be engaged to meet the pressure rating as published in the specifi cations. Use the 8506X models for inline installations where the electronics must be separated from the electrode. Conductivity electrodes with sanitary fl ange fi ttings must be installed using this option Conductivity/Resistivity Sensor Electronics

2 4 to 0 ma Wiring Maximum length of 4 to 0 ma loop is 00 meters (000 ft) 9 VDC to 6 VDC ma Loop Output V 4 Sensr Gnd (SHIELD) 4 Temp. IN (WHITE) SW D Signal RTN (BLK) Signal IN (RED) Digital (S L) Wiring The Digital (S L) output is compatible with the Signet 8900 MultiParameter Controller and the Signet 9900 Transmitter. Refer to the wiring sections of the 8900 or 9900 manual to determine cable length limitations. IMPORTANT: Provide Earth Ground as indicated by symbol. I/O Module X Freq. (Red) GND (Shield) Freq. (Red) OR S L S L (Red) GND (White/Shield) +5VDC (Black) S L S L (Red) GND (White/Shield) Analog Output Analog Output C Gnd Data SW 4 D Sensr Gnd (SHIELD) Temp. IN (WHITE) Signal RTN (BLK) Signal IN (RED) Note: The 898 and 8984 sensors can connect directly to the 9900 via the 9900's optional Direct Conductivity/Resistivity Module ( ) S L GND DATA SHLD DC Power Loop Voltage White Red Black H COMM Module Dual Digital (S L) Wiring Dual is available on Digital (S L) output model 8506 only, for use with the Signet 8900 MultiParameter Controller. Sensors may be the same or different cell constants. If the Dual model is used with a single sensor, connect the sensor to and set all of the switches to OFF (OPEN). I/O Module X Freq. (Red) GND (Shield) Freq. (Red) OR S L S L (Red) GND (White/Shield) +5VDC (Black) S L (Red) GND (White/Shield) Analog Output + Analog Output + Dual applications usually include one sensor with a smaller cell constant and one sensor with a larger cell constant. Place the larger cell constant on. S L C Gnd Data SW 4 4 D Sensor Sensor This allows periodic recalibration of the larger cell by simply turning OFF (OPEN). IMPORTANT: Provide Earth Ground as indicated by symbol. 850 Conductivity/Resistivity Sensor Electronics 5

3 Cell Constant Selection Single 850 Electronics (8505, 8505, 8506, 8506) Single input models use only SW. Use SW # to select the cell constant for the fi rst sensor. Use SW #4 to disable the PT000 Temp Compensation function in the 850 (as required for USP applications). Recommended: Make all switch settings before supplying power. Switch changes made after supplying power will take 5 to 0 seconds before becoming effective. D SW SW 4 SW SW Integral 850 Systems (Single ) The 8505XX and 8505XX are shipped from the factory with the custom cell constant and temperature offset programmed into the singleinput electronics. SW will be preset to "Custom cell constant". No additional modifi cations are required. Replacing Integral System Electrode or Electronics When installing a new conductivity electrode or replacing System Electronics, the SW switches must be confi gured to select the appropriate cell constant. See Single section above. Leaving SW in the custom cell constant confi guration will effect accuracy. Use calibration standards to calibrate (see page 8). Dual 8506 Electronics Switch banks SW and SW4 are used to select the cell constant of the electrodes. Use SW # to select the cell constant for the fi rst sensor. Use SW #4 to disable the PT000 Temp Compensation function in the 850 (as required for USP applications). This disables the function for BOTH INPUTS. Use SW4 # to select the cell constant for the second sensor. Set SW4 #4 to OPEN to disable. Recommended: Make all switch settings before supplying power. Switch changes made after supplying power will take 5 to 0 seconds before becoming effective. D 4 4 SW4 NOTE: Dual applications usually include one sensor with a smaller cell constant and one sensor with a larger cell constant. Place the larger cell constant on. This allows periodic recalibration of the larger cell by simply turning OFF (OPEN). 4 4 NOTE: To work correctly with the 9900, the 850 must be set for the custom cell constant or the actual electrode cell constant and the 9900 set for a.0 cell constant. SW or SW4 Custom Cell Constant 4 0.0/cm 4 0./cm 4.0/cm 4 0.0/cm 4 0.0/cm 4 Examples SW = Cell Constant and Temperature Compensation # # # #4 Cell Constant C C C O Custom C O O O 0.0 cm O C O O 0. cm C C O O.0 cm O O C O 0.0 cm C O C O 0.0 cm #4: (O) = Temp Comp ACTIVE (C) = Temp Comp INACTIVE SW4 = Cell Constant and # # # #4 Cell Constant C C C O Custom C O O O 0.0 cm O C O O 0. cm C C O O.0 cm O O C O 0.0 cm C O C O 0.0 cm #4: (O) = INACTIVE (C) = ACTIVE.0 cell constant, temp comp Active 4.0 cell constant, temp comp Inactive Conductivity/Resistivity Sensor Electronics

4 Range Selection for 4 to 0 ma Output The Range selection switch bank (SW) provides eight range selections for each cell constant. Each range can be inverted, making a total of 6 range options. Select a range from the table below and set SW as indicated. 4 SW Example (refer to shaded selections of chart): The electrode installed is the 840V, with a 0.0 cell constant. The required output is 4 to 0 ma = 0 to 00 μs. Set SW switch bank to CCOO. To invert range (4 to 0 ma = 00 to 0 μs), close switch #4. SW 4 SW D 4 SW SW Switch Setting 0.0 Cell 0.0 Cell.0 Cell 0.0 Cell 0.0 Cell # # # #4 Resistivity Ranges in BOLD C C C O 0 to 0 MΩ 0 to μs 0 to 0 μs 0 to 00 μs 0 to 400 μs C C C C 0 to 0 MΩ to 0 μs 0 to 0 μs 00 to 0 μs 400 to 0 μs O C C O to 0 MΩ 0 to 5 μs 0 to 50 μs 0 to 500 μs 0 to 000 μs O C C C 0 to MΩ 5 to 0 μs 50 to 0 μs 500 to 0 μs 000 to 0 μs C O C O 0 to MΩ 0 to 0 μs 0 to 00 μs 0 to 000 μs 0 to 000 μs C O C C to 0 MΩ 0 to 0 μs 00 to 0 μs 000 to 0 μs 000 to 0 μs O O C O 0 to μs 0 to 50 μs 0 to 500 μs 0 to μs 0 to μs O O C C to 0 μs 50 to 0 μs 500 to 0 μs to 0 μs to 0 μs C C O O 0 to 5 μs 0 to 00 μs 0 to 000 μs 0 to μs 0 to μs C C O C 5 to 0 μs 00 to 0 μs 000 to 0 μs to 0 μs to 0 μs O C O O 0 to 0 μs 0 to 00 μs 0 to 000 μs 0 to μs 0 to μs O C O C 0 to 0 μs 00 to 0 μs 000 to 0 μs to 0 μs to 0 μs C O O O 0 to 50 μs 0 to 500 μs 0 to μs 0 to μs 0 to μs C O O C 50 to 0 μs 500 to 0 μs to 0 μs to 0 μs to 0 μs O O O O 0 to 00 μs 0 to 000 μs 0 to μs 0 to μs 0 to μs O O O C 00 to 0 μs 000 to 0 μs to 0 μs to 0 μs to 0 μs NOTE: Switch #4 inverts the loop output range (O) = 4 to 0 ma (C) = 0 to 4 ma 850 Conductivity/Resistivity Sensor Electronics 7

5 Calibration All 850 Conductivity/Resistivity Sensor Electronics are factory calibrated for maximum outofthebox accuracy. The EasyCal feature allows calibration to be performed at the sensor. The 8984 Conductivity sensors come with a certifi cate of calibration. This certifi cate provides information regarding the actual cell constant and temperature offset as tested and verifi ed according to NIST standards. This information has been programmed into the 850 electronics as its default factory value. If required, the sensor can be recertifi ed by contacting the GF Signet repair department. a. SW: 4 to 0 ma output range selection switch bank b. Power and Output terminal block: 4 to 0 ma or Digital (S L) Outputs c. SW and SW4: Electrode Cell Constant selection switch banks d. D: LED indicator e. SW: EasyCal Pushbutton f. & : Conductivity Electrode connections b c a SW SW4 SW f NOTE: When the electrode is changed from its original factory provided electrode or the application requires a cell constant change, reset SW or SW4 switches (see page 6). Then perform a wet calibration with calibration standards. d SW D e EasyCal EasyCal is a singlepoint calibration system. During this procedure, if the measured value is within ±0% of any of the test values listed below, the 850 will automatically recognize the test value and calibrate the output to that value. NOTE: The fi rst step (Reset) is recommended each time an electrode is replaced, but is NOT necessary upon initial installation or periodic calibration.. Reset the 850 Sensor to factory calibration: Set all switches on SW (and SW4 for Dual ) to OPEN. Apply power, wait at least seconds, then press and hold SW until the LED (D) comes on steady then goes off again (approx. 0 seconds). When the LED goes off, release SW; reset is complete. Reset SW and SW4 to the proper settings.. Place the electrode/sensor assembly into the conductivity test solution appropriate to your operating range. Shake the electrode to dislodge any air bubbles visible on the surface of the electrode μs, μs, 856 μs (per ASTM D595) 0 μs, 00 μs, 00 μs, 500 μs, 000 μs, 5000 μs, 0,000 μs, 50,000 μs, 00,000 μs. Allow at least minutes for the electrode response to stabilize.. Press and hold SW for approximately 8 to 0 seconds. During this time, the LED will come on steady then go back off. (If the LED blinks several times rapidly, the calibration was not successful. See the troubleshooting section). Calibration is complete. Return the system to service. Dual Calibration Dual 8506 Electronics The 8506 can only be calibrated if both inputs are used, or if is disabled. To disable : Set SW4, #4 to OPEN. Place each sensor into a test solution that represents the operating range of that sensor. When SW is pressed, the 850 will calibrate both inputs simultaneously. Dual applications usually include one sensor with a smaller cell constant and one sensor with a larger cell constant. Place the larger cell constant on. This allows periodic recalibration of the larger cell by simply turning OFF (OPEN) Conductivity/Resistivity Sensor Electronics

6 Maintenance The 850 requires no periodic maintenance. Coatings on the electrode may cause slow response or drift. Clean metallic surfaces with a mild detergent and a nonabrasive brush or cotton swab. Troubleshooting LED and Output Condition Possible Causes Suggested Solutions Current Out: LED off, current output is ma (S L) out: "Check Sensor" During EasyCal, the LED blinks rapidly for 4 seconds. After completing calibration procedure, the output values are inaccurate. The output of the 850 indicates a value that is off by a factor of 0 (e.g. 0x, 00x the correct value) SW and SW4 set to all OPEN (factory setting). No electrode installed. SW (and SW4) not set correctly. System not ready. Measured value of the test solution is outside the ±0% tolerance. The electronics or the electrode is defective. Insuffi cient time allowed for electrode stabilization during calibration procedure. Test solutions are contaminated. EasyCal performed with temp comp Inactive, then temp comp Active for measurement. (or vice versa) The cell constant selection on the 850 (SW or SW4) does not match the actual input. Normal for new system. Install electrode. Set SW and SW4 correctly. Retry (recycle power). Use fresh test solutions and restart the calibration. Replace the electronics or the electrode. Recalibrate and wait at least minutes after placing electrode in solution before pressing SW. Use fresh test solutions and restart the calibration. Match the 850 switch settings to agree with the sensor being used. 850 Conductivity/Resistivity Sensor Electronics 9

7 Electronic Certification Signet offers conductivity simulators in fi ve different values. These tools enable the user to validate the performance of the electronics independently of the electrode. This requirement is defined by ASTM D 595 (Standard Test Methods for Electrical Conductivity and Resistivity of Water) which is commonly used for USP 4 applications. Cond. Resist. 5 C For use with Signet 850 Conductivity NIST Traceable ( ).0 μs ±0.% ( ).5 μs ±0.% ( ) 0.0 μs ±0.% ( ) 8. MΩ ±0.% ( ) 0.0 MΩ ±0.% Before using the Simulator: Before using the simulators, disconnect all electrodes and reset the 850 Electronics to factory calibration:. Set all switches on SW (and SW4 for Dual ) to OPEN. Turn the power on, wait at least seconds. Press and hold SW until the LED (D) comes on steady then goes off again (approx. 0 seconds).. When the LED goes off, release SW. Reset is complete. To validate :. Turn the power off.. Set SW to accept a 0.0 cell constant. Leave SW4 in the allopen position.. Install the simulator into the 850 at the conductivity electrode terminals. 4. Connect the 850 output terminals to the appropriate display instrument. Turn the power on. The display should indicate a conductivity value within ±% of the simulator value. If the output is x0 or x00 of the correct value, recheck step. The 850 is not set to accept a 0.0 cell constant. If the correct value is displayed, the electronics are calibrated to ASTM D 5 specifi cations. Remove the simulator and reset SW to the correct cell constant before reinstalling the electrode. If the correct value is not displayed, contact the factory. To validate :. Turn the power off.. Set SW4 to accept a 0.0 cell constant.. Install the simulator into the 850 at the conductivity electrode terminals. 4. Set SW switches to the allopen position. 5. Turn the power on and repeat step 4. Remember to reset all switches to their correct position before resuming normal operation Conductivity/Resistivity Sensor Electronics