VEGA Capacitive electrodes EK 4 … 20 mA - Compact - Manual (Page 37)

Capacitive electrodes EK 4 … 20 mA - Compact 37
22574-EN-020809
28
30
32
+
–
+
–
+
–
mA V
4 … 20 mA 12 … 20 V
Sensor
Diagnosis
5.4 Fault rectification
Fault Rectifying measure
Current value Check the sensor inputs for the following causes of faults:
≥
22 mA - short-circuit on the input
- sensor not connected correctly
- sensor cable interrupted
- supply voltage too low or too high
Measure the current on the connection cable to the sensor.
Under normal conditions, the terminal voltage of the sensor is at least
12 V.
In Ex systems, make sure that the Ex protection is not influ-
enced by the measuring instruments.
Current value > 22 mA
- Check all connections and the connection cable to the sensor.
- Loosen the two small screws with a Phillips screwdriver and remove
the oscillator from the plug connection.
- Measure the current.
• If the current value remains > 22 mA, then the oscillator is
defective. Exchange the oscillator.
• If the current value is < 22 mA, the the electrode is defective.
Return the electrode for repair.
e.g. VEGATOR
12 … 36 mA