December 2021
Service Manual
MDE 252 Rev. 1
Troubleshooting
18
Section 2: Troubleshooting
2.2.15
Alarm on Local Display: Request Signal
REQUEST SIGNAL
1.
The analogue 4 - 20 mA signal is not within the preset range (from 4 to 20) and the actuator does not
work in accordance to the sent analogue signal.
2.
The actuator operates in Local mode and in remote hardwired with Open/Close/Stop commands only.
Verify the values (4 - 20 mA) of the analogue control signal sent to the
actuator at terminals B8-B9 on terminal board.
Connect a 4 - 20 mA signal source to terminals B9-B9. Set the signal source at
4 mA. Check that on local LCD display the value R: xxx% reports the value zero
with a tolerance of +/-0,5%.
Please recalibrate the 4 - 20 mA analogue
input; enter the "restricted menu" with the
service password and set the new value of
the parameters.
Connect a 4 - 20 mA signal source to
terminals B9-B9. Set the signal source at
20 mA. Check that on local LCD display the
value R: xxx% reports the value 100 with a
tolerance of +/-0.5%.
Please recalibrate the 4 - 20 mA analogue
input; enter the "restricted menu" with the
service password and set the new value of
the parameters.
If the problem still exist, replace the
4 - 20 mA board.
If the problem still exist, replace the
4 - 20 mA board.
Are values correct?
Are values correct?
Are values correct?
NO
NO
NO
YES
YES
YES
The issue is not related
to the actuator.
Problem
solved.
