10
8850-3 Conductivity/Resistivity Transmitter
Display Condition
Suggested Solutions
Possible Causes
"- - - -"
Value Must be less
than 3
Value must be greater than 0
"Value must be
400 or less"
Display erratic, shows "0" or
"------"
intermittently
"Too much Error
Check Sensor"
Display is over range. This may be a
normal condition if your process operates
at/near the limits of the sensor range.
k
Ω
or M
Ω
units selected and sensor is
open.
The PPM factor must be a value from
0.00 to 3.00.
Custom cell constant cannot be set to 0.
Pulse Rate cannot be greater than 400.
Aux Power not connected.
• Defective or dirty/coated sensor.
• Wiring error.
• Fluid conductivity too low.
• Defective temp element.
• Check sensor for correct range.
• Check Decimal setting in OPTIONS menu.
Check Calibrate menu settings for incompatible
SOURCE and RANGE values.
Set a PPM value less than 3.
Set cell constant to a value greater than 0.
Set a pulse rate value less than 400.
Wire 8850 according to diagram (Section 3.1).
• Clean or replace sensor.
• Check and correct wiring.
• Replace sensor.
Troubleshooting
If a Current Loop is locked at 3.6 mA, the problem is related to the temperature circuit:
This occurs only if the 8850 detects a resistance from the temperature sensor that is less than 250
or greater than 2800
.
• Check the sensor wiring for open/short or poor connections on white (TEMP IN) and black (ISO GND)wires.
• The PT1000 temperature device in the sensor is defective.
• The transmitter is defective.
Auxiliary Power (terminals 1 and 2) must ALWAYS be connected for the 8850 to operate.
Technical notes
