SEPAM relay with MET1482 module displaying RTD fault and **** or _**** for temperature readings.

Issue
The front display shows a RTD Fault and the temperature reading is **** or _****.

Product Line
SEPAM MET148-2

Environment
Wiring RTDs

Cause
The RTD module is not reading the RTDs correctly from the motor, generator, or transformer.

Resolution
An "RTD FAULT" alarm is generated whenever one of the RTDs is detected as being short-circuited or disconnected (absent).
Since the alarm is common to the 8 channels of the module, go to the temperature measurement display screen to determine which channel is affected by the fault.
Measurement displayed:
Tx.x = -**** = RTD disconnected (T > 205 °C (401 °F))
Tx.x = **** = RTD short-circuited (T < -35 °C (-31 °F))

To resolve the issue try the steps below:
1. Shield for RTD is connected on both ends.  The RTD shield needs to only be connected on one end not both.  The RTD shield is recommended to be connected at the MET1482 module only.
2. The RTD sensor is not configured correctly. The RTD sensor is set in SFT2841 by clicking the ... box next to the MET1482 enable section under the SEPAM configuration tab (below screenshot is from a SEPAM M20 relay).

3. The RTD's are two wire with a shield and not three wire with a shield. While this is not supported it may be made to work by jumpering terminals 1 and 2 for each RTD.
4.  The RTD wires are loose.

Publicado para:Schneider Electric Portugal