Walchem WebMaster, Инструкция по эксплуатации

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Temperature Sensor Error
This error message is caused by the temperature signal being outside the normal range (around
1500-33,000 ohms for contacting conductivity sensors, 15,000 to 330,000 for electrodeless
conductivity sensors, 1000 to 1400 ohms for pH sensors and high temperature conductivity
sensors). Any relay controlled by the faulty sensor will be forced off.
Possible Causes Corrective Actions
Faulty temperature sensor wiring Measure the temperature signal using an
ohmmeter between the green wire and the
green/white wire as close to the sensor as
possible, with the wires disconnected from the
terminal strip. This should be around 8,000
ohms at 85 F, 30 C for a contacting electrode,
80,000 ohms for an electrodeless sensor,
and 1115 ohms for a pH or high temp sensor.
If OK, check this again at the terminal strip of
the circuit board. If OK, make sure that the
wires are connected firmly to the correct
terminals.
Faulty conductivity sensor.
If you measure resistance outside the
acceptable range directly from the sensor,
replace the sensor.
Faulty sensor input board
Go to the Conductivity Input Page and
perform a self test. If this passes, then the
problem is with the sensor or its wiring. If it
fails, then disconnect the sensor from the
circuit board and try the self test again. If it
still fails, replace the circuit board.
Total Alarm Limit
The totalizer for a flow meter input or counter input has exceeded its programmed maximum limit.
Possible Causes Corrective Actions
The system has experienced too high a total Evaluate system
You are getting false contacts.
Go to the appropriate Input Page and verify
that the total is increasing even when the
solution is not flowing.
Disconnect the input’s cable from the
controller and verify that the total stops
increasing. Route the input’s cable away
from any AC voltage and make sure that the
cable is shielded.