Fluctuating Process Values - Siemens SITRANS F M MAG 1100 Operating Instructions Manual

4. Remote mounted transmitter has a 3 core cable with an overall shield continuously from
sensor to transmitter, including junction boxes and terminal rails inside panels.
5. Shield is connected to 0 or to earth terminal (PE) on sensor.
Note
Sensors removed from line
For sensors removed from line with dry bore, use megger between terminal 82 and
compression plate, and 83 and compression plate to show any water ingress behind
electrodes or within enclosure.
See also
Coil resistance (Page 66)
7.3

Fluctuating process values

Question
Why do the displayed process values fluctuate when the electrode cable is moved?
Answer
There are several causes of the fluctuating process values:
● Deposits on electrodes
– Clean the electrodes.
● Defect electrode cable
– Replace the cable
● Incorrect cable connection
– Connect the electrode cable (82, 83, 0 and shield) according to the instructions in
SITRANS F M MAG 1100 sensor
Operating Instructions, 01/2018, A5E03433301-AC
Connecting (Page 33)
Note
Vibrating environments
It is recommended to use special low noise cables for sensor sizes DN 2 and DN 3
installed in vibrating environments.
Troubleshooting
7.3 Fluctuating process values
47