Tap-Changer Operation Troubleshooting - Eaton Cooper Power Series Installation, Operation And Maintenance Instructions

Tap-changer operation troubleshooting

The regulator will not operate manually or
automatically
Connect a voltmeter between TB
1.
the CONTROL FUNCTION switch on Manual.
Toggle the Raise switch and measure the voltage
2.
between terminals R
The voltage reading should approximate the set voltage
setting.
Place the voltmeter hot lead on TB
3.
the Lower switch.
Measure the voltage between terminals L
4.
terminal board TB . The voltage reading should approxi-
1
mate the set voltage value.
5. If correct voltage readings are obtained in Steps 2 and 4,
the trouble may be in the position indicator, junction box,
control cable, or motor capacitor. Refer to the junction
box troubleshooting section of Service Information
MN225008EN VR-32 Voltage Regulator with Quik-Drive
Tap-Changer Installation, Operation, and Maintenance
Instructions.
6. If there is no voltage measurement in either Step 2 or
4, make a corresponding measurement (R
L to G) on lower terminal board TB
3
7 . If the voltages measured in Step 6 are approximately
the set voltage value, then the fault is likely a loose
connection or a faulty terminal between TB
8. If Steps 2, 4, and 6 do not provide voltage readings,
measure the voltage between VM and G on terminal
board TB . The reading should approximate the set
2
voltage value.
9. If Step 8 does not yield a voltage measurement, check
the voltage between PD
voltage disconnect knife switch.
10. If Step 8 does not yield a voltage measurement, check
the voltage between PD
voltage disconnect knife switch.
A. If the set voltage value is approximately obtained,
the V disconnect or the ratio-correcting transformer
1
(RCT ) of the rear panel signal circuit is probably faulty.
1
B. If voltage is not obtained, the trouble is in the
control cable, junction box, or regulator tank. Refer to
the junction box troubleshooting section of Service
Information MN225008EN VR-32 Voltage Regulator
with Quik-Drive Tap-Changer Installation, Operation,
and Maintenance Instructions. If the junction box
checks are satisfactory, the trouble is in the regulator
tank. See Service Information S225-12-1 QD3 Quik-
Drive Voltage Regulator Tap-Changer Manual and
Service Information S225-10-19 Voltage Regulator
Quik-Drive T875 Tap-Changer Switch; Operating,
Maintenance, Troubleshooting and Parts Replacement
Instructions for troubleshooting methods.
104 CL-6 SERIES CONTROL INSTALLATION, OPERATION, AND MAINTENANCE INSTRUCTIONS MN225016EN January 2016
-R and TB
1 1
and G on terminal board TB
1
-L
, then toggle
1 1
and G on
1
to G and
3
.
2
and TB
1
-1 (V1) and ground (G) at the
1
-1 (V1) and ground (G) at the
1
Motor capacitor problem
A problem in the motor capacitor can prevent a regulator
from operating manually or automatically. To check the
motor capacitor, use the following steps:
-G. Set
1. Connect a voltmeter from TB
1
2. With the control powered up, place the Auto/
Remote/Manual switch on Manual.
.
1
3. Using the Raise/Lower Switch, give a Raise signal.
4. The voltmeter reading should approximate the set
voltage.
5. With the voltmeter still connected to TB
a lower signal.
6. The voltmeter should read a capacitive voltage. This
voltage could be somewhere between 60 and 90 Vac.
A voltage reading on TB
7 .
reading is a sign of a bad capacitor.
To double check, place the voltmeter lead on TB
8.
9. Use the Raise/Lower switch, and give a Lower signal.
10. The voltmeter reading should approximate the set voltage.
11. With the voltmeter still connected to TB
a Raise signal.
12. The voltmeter should read a capacitive voltage. This
voltage could be somewhere between 60 and 90 Vac.
13. A voltage reading on TB
.
2
reading, is a sign of a bad capacitor.
14. If both the raise and lower circuit reads 0 V, or a mV
reading, when there should be a capacitive voltage,
then the motor capacitor is open. The capacitor will
need to be replaced.
Operation counter does not indicate tap change
If the operation counter does not indicate tap changes,
check the following:
The voltage signal at TB
1.
mately 120 Vac when a tap change is made. When this
voltage signal is applied, the control panel operation
counter will be updated.
Measure the voltage at TB
2.
changer is given a command to tap, in manual mode,
by the Raise/Lower toggle switch. If the voltage
signal is present, the problem is either in the control
connector or the control.
3. If the voltage signal is not present at TB
the problem could be in the back panel wiring harness
connections at TB
tion box connections, or the holding switch on the tap
changer.
4. Check the voltage signal at TB
is not present at these points; keep tracing the signal
back through the components back into the regulator.
-R to G.
1 1
-R
1
-R to G of 0 V or a mV
1 1
-L
1
-L to G of 0 V, or a mV
1 1
-R and L
should be approxi-
2 3 3
-R or L
when the tap-
2 3 3
-R
2
-R or L
, the control cable, junc-
1 1 1
-R or L . If the signal
1 1 1
to G, give
1
-L to G.
1 1
to G, give
1
or L ,
3 3