14
COSYS R 12H Regulator - Ref.: 539972A
Error Possible cause Corrective action
1 The regulator is not operating.
No display on the screen.
No mains voltage. Check that the regulator has the
correct feed.
2 The display shows U=0
and is flashing.
Regulator measurement voltage too
low.
Check the measurement voltage
connection is correct.
3 The regulator is not responding to
manual activation (Feed and display in
good condition).
Activation delay not taken into consi-
deration.
If the display indicates for
example "1.ON", wait for the
regulator to engage the first
stage.
Manual mode not confirmed. Press the "aut/man" button until
the "manual" LED flashes
4 Stages indicated as activated whereas
the switches are not activated.
Control badly connected or control
voltage missing.
Check the wiring against the
connection diagram. Check the
fuses.
5 The regulator remains in the automatic
recognition procedure.
Unstable network (large fluctuations in
cos phi).
Wait for more stable network
conditions. Enter the c/k values
and connection type manually.
6 During the automatic measurement
procedure, the display shows C=0.
Error in the control loop (The switches
are not engaging).
Check the wiring against the
connection diagram. Check the
fuses.
Missing or defective fuses. Check there is voltage at the
capacitor terminals after they are
engaged.
CT badly positioned. Check the installation of the CT.
7 The display indicates "I=0" and is
flashing.
CT connection faulty or short circuiting. Check the measurement current
value (Imin>0.02A)
The measurement current is too low. Fit a smaller rated CT
Faulty CT. Check the CT operates correctly
8 Under automatic operation and with an
inductive load, no activation is taking
place.
The parameter settings of the c/k, time
delay or discharge settings are too
high.
Change the programmed values.
Modify as required.
The c/k value is not recognised in auto-
matic operation.
Conform the connection of the
control against the wiring diagram
and reinitiate the procedure.
Several measurement instruments
(for example ammeters) connected in
parallel to the regulator.
Install the different measurement
instruments in series.
9 Under automatic operation, a stage is
regularly engaged and disengaged.
Strong variations in load; time delay
too low.
Increase the time delay.
The c/k value programmed for the
regulator is too low.
Enter the c/k value in compliance
with the table.
TROUBLESHOOTING