Cooper VR-32 Installation, Operation And Maintenance Instructions page 9

Figure 1-8.
Position Indicator.
Setting The Limit Switches
Before setting the limit switches, be sure the new settings
will not conflict with the present tap changer position. Do not
set the switches below the indicated tap changer position.
For example, if the indicator hand is at step 12 and the
change to be made is from plus or minus 10% (step 16) to
plus or minus 5% (step 8), run the tap changer back to step
7 or less, manually. Then set the limit switches for plus or
minus 5% regulation.
Limit switches should be set in anticipation of the maxi-
mum deviation of primary voltage. For example, on a circuit
where 7200 volts is to be maintained, plus or minus 10% will
permit voltages between 6480 and 7920 to be regulated
effectively. For voltages outside of this range, the regulator
will not be able to return the voltage to the preselected level,
in this case 7200 volts. The tap changer will have stepped to
the maximum tap position and will be unable to regulate fur-
ther. Five % regulation would accommodate circuit voltages
between 6840 and 7560, maintaining 7200 volts for all volt-
ages in this range.
To set the limit switches. follow this two-step procedure:
1. Loosen the captive bezel securing screws and swing the
bezel open.
2. Lift the limit switch adjustment lever free of the detent and
slide it to the new setting allowing the lever to snap into
the detent stop.
TABLE 1-2
ADD-AMP Capabilities.
Load Current Ratings (amps)
Rated Rated
Volts kVA
± 10%**
25 100/112
50 200/224
75 300/336
100 400/448
2500 125 500/560
167 668
250 1000/1120
333 1332/1492
416.3 1665/1865
25 50/56
50 100/112
100 200/224
125 250/280
5000 167 334/374
250 500/560
333 668
416.3 833/900
38.1 50/56
57.2 75/84
76.2 100/112
114.3 150/168
167 219/245
7620 250 328/367
333 438/491
416.3 548/614
500 656/668
667 875/900
833 1093/1224
69 50/56
138 100/112
207 150/168
276 200/224
13800 414 300/336
500 362/405
552 400/448
667 483/541
833 604/668
72 50/56
144 100/112
288 200/224
333 231/259
416 289/324
14400 432 300/336
500 347/389
576 400/448
667 463/519
720 500/560
833 578/647
50 25.1/28
100 50.2/56
200 100.4/112
19920 333 167/187
400 200.8/224
500 250/280
667 335/375
833 418/468
o
**55/65 C rise rating on VR-32 regulators gives an additional 12%
increase in capacity if the tap changer's maximum current rating has
not been exceeded. For loading in excess of the above values please
refer to the factory.
S225-10-5
Regulation Range
± 8-3/4% ± 7% ± 6-1/4%
110 120 135
220 240 270
330 360 405
440 480 540
550 600 668
668 668 668
1000 1000 1000
1332 1332 1332
1665 1665 1665
55 60 68
110 120 135
220 240 270
275 300 338
367 401 451
550 600 668
668 668 668
833 833 833
55 60 68
83 90 101
110 120 135
165 180 203
241 263 296
361 394 443
482 526 591
603 658 668
668 668 668
875 875 875
1093 1093 1093
55 60 68
110 120 135
165 180 203
220 240 270
330 360 405
398 434 489
440 480 540
531 580 652
664 668 668
55 60 68
110 120 135
220 240 270
254 277 312
318 347 390
330 360 405
382 416 468
440 480 540
509 556 625
550 600 668
636 668 668
28 30 34
55 60 68
110 120 135
184 200 225
220 240 270
275 300 338
369 402 452
460 502 564
± 5%
160
320
480
640
668
668
1000
1332
1665
80
160
320
400
534
668
668
833
80
120
160
240
350
525
668
668
668
875
1093
80
16
24
32
48
579
64
668
668
80
16
320
37
462
480
555
64
668
668
668
40
80
16
267
32
400
536
668
1-9