ROHRBACK COSASCO SYSTEMS CORRATER 9020, User Manual

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9
Verification of Instrument Operation
To verify the proper operation of the 9020-OEM or 9020 instrument, the P/N 710920 Test
Probe is used. The test probe should be connected to the connector on the end of the probe
cable and the switches on the transmitter set in accordance with the following:
Switch
Position Value
CORROSION
RANGE 2 20 MPY
IMBALANCE RANGE
2 20 Imbalance Units
CYCLE TIME RANGE
0 5 Minutes
ALLOY
MULTIPLIER 1,0,0 1.00
STANDARD/FLUSH STANDARD
Apply power to the 4-20 mA. loop and observe the loop current after the measurement cycle
has been completed (approximately 5 minutes). The CORROSION RATE loop current
should be 8.00
∀
0.25 mA. and/or the IMBALANCE loop current should be 4.00
∀
0.1 mA.
Note that the above settings include the switch settings for the transmitter used for monitoring
both CORROSION RATE and IMBALANCE, however it is not necessary to power the second
loop in order to complete the verification testing.
Selection of Parameters for Corrosion Rate Monitoring
To place the transmitter into operation, disconnect the Test Probe and connect the cable to
the CORRATER

probe to be monitored.
Set the CORROSION RANGE switch to the position that exceeds the maximum corrosion
rate to be expected, i.e. Position 2 (20 MPY) if the maximum expected rate is 12 MPY. Set
the IMBALANCE RANGE to 0 (No Measurement) if this function is not used.
Set the IMBALANCE RANGE switch to the position that exceeds the maximum imbalance
reading that is expected. The scale factor for this measurement is 0.5 microamperes (
Φ
A.)
per square centimeter of electrode area. Standard electrodes are 5 square centimeters in
surface area, therefore one imbalance unit is 2.5
Φ
A.
Set the CYCLE TIME RANGE for the desired measurement cycle time. For water with
conductivities greater than 100
Φ
S., any cycle time of 5 minutes or more should be
satisfactory. For lower conductivity water, or when filming type inhibitors are in use, it is
recommended that the 20 minute cycle time be selected first. After consistent readings are