Control Calibration
All controls are factory-calibrated and should not need to
be recalibrated by user. However, calibration can be per-
formed for both the voltage and current circuits as follows:
Voltage Calibration
.
Connect an accurate true-RMS-responding voltmeter
to the voltmeter terminal. This voltmeter should have a
base accuracy of at least 0.1% with calibration trace-
able to the National Bureau of Standards.
2 .
Connect a stable 50/60 Hz voltage source (with less
than 5% harmonic content) to the External Source ter-
minals.
3 .
Set the
POWER
switch to
External
.
4 .
Adjust the voltage source to provide 120.0 V to the
control, as read on the reference voltmeter.
5 .
Before calibration can be performed, Security Level 3
must be activated by entering the proper security code
at FC 99, Security Code.
Function
,
99
,
Enter
;
32123
(default),
Enter
.
6 .
The display will show the voltage applied to the control.
This should correspond to the reading on the reference
voltmeter. If the control reading is significantly different,
the calibration can be altered by pressing
Edit
, keying
in the correct voltage as displayed on the reference
meter, and pressing
Enter
. The voltage circuit is now
calibrated.
Current Calibration
.
Connect an accurate true-RMS-responding ammeter
in series with the current source.
2 .
Connect a stable 60/50 Hz current source (with less
than 5% harmonic content) to the reference ammeter
and to the current input terminals
C
and
C3
on fan-
ning strip
TB2
(C1 is identified by a red wire, and C3 is
identified as the green wire).
3 .
To power the control, connect a 120 V ac voltage
source to the
EXTERNAL SOURCE
terminals.
4 .
Place the power switch on
External
.
5 .
Adjust the current source to provide 0.200 A to the
control, as read on the reference ammeter.
6 .
Before calibration can be performed, Security Level 3
must be activated by entering the proper security code
at Function Code 99, Security Code.
Function
, 99,
Enter
, 32123 (default),
Enter
The proper level is now activated.
7 .
Access Function Code 48, Current Calibration.
Function
,
48
,
Enter
.
8 .
The display will show the current applied to the control.
This should correspond to the reading on the reference
ammeter. If the control reading is significantly differ-
ent (greater than 0.6 mA error), the calibration can be
altered by pressing
Edit
, then entering the correct cur-
rent as displayed on the reference meter, followed by
Enter
. The current circuit is now calibrated.
CL-6 Control Panel
Troubleshooting
No Power
Check the 6 A fuse on the control front panel. Remove the
motor fuse from the control and check for continuity across
the fuse. Spare fuses are shipped with each control and
are located in the control box.
Note:
Use only 250 V ac fuses of the proper current rating.
Failure to do so may cause unnecessary fuse operation
or insufficient protection of the regulator and control.
If the fuse has blown, the tap-changer motor will not run.
If the 6 A fuse is okay, set the front-panel power switch to
Internal Power
and check the following :
.
With a voltmeter, check
Tb
2
-V
S
to
G
. The voltage
should approximate the set voltage. If the voltage is
present at
Tb
2
-V
S
, then the problem is in the control.
Replace the control.
2 .
Check the voltage-disconnect knife switch
V
1
,
V
6
(if
present), and the current shorting knife switch
C
of
the back panel in the control enclosure. Close the
V
1
and
V
6
voltage switches if open. Open the CT shorting
switch if closed.
33
S225-10-30
!
SAFETY
FOR LIFE
CAUTION:
Equipment Damage. Be mindful of polar-
ity when using an external source. Polarity reversal will
result in control damage.
VR-T201.0
WARNING:
Explosion Hazard. Verify that both
the neutral light and the position indicator hand
indicate neutral when the tap-changer is physically in the
neutral position. Lack of synchronization will cause an
indefinite indication of NEUTRAL. Without both indica-
tions of neutral, bypassing of the regulator at a later time
will not be possible, and the line must be de-energized
to avoid shorting part of the series winding. Failure to
comply can result in serious personal injury or death and
equipment damage.
VR-T212.0
