Table 7-8.--Controls and Indicators for the AC Control Panel
No.
NOMENCLATURE
DESCRIPTION
FUNCTION
1
PHASE SEQUENCE
Indicating light with
Glows brightly if phase sequence of ac input is
ABC
white lens
A to B to C.
2
HOUR METER
Elapsed time totalizing
Indicates accumulated time during which
counter
control power is active in load bank.
3
PHASE SEQUENCE
Indicating light with
Glows brightly if phase sequence of ac input is
CBA
white lens
C to B to A.
4
FREQUENCY
Frequency meter
Indicates frequency of ac input.
5
AC LOAD PROGRAM
3-position rotary switch Selects ac loading program: continuous, 5-min
SELECTOR
timed, or 5-sec timed.
6
OVERVOLTAGE
Spring-loaded,
Manually resets control circuits and ac loading
RESET
2-position toggle
circuits after an ac overvoltage cutout, provided
switch
that phase A to neutral voltage is 125 V or less.
7
POWER FACTOR
Power factor meter
Indicates power factor of applied load in phase
determined by METER PHASE SELECTOR
switch.
8
4-position rotary switch Selects current range indicated by AC AMPS
WATTMETER RANGE
meter and power range indicated by SINGLE
SELECTOR
PHASE KW meter. Ranges are:
0 to 200A and 0 to 20 KW,
0 to 400A and 0 to 40 KW,
0 to 800A and 0 to 80 KW,
0 to 1600A and 0 to 160 KW.
9
SINGLE PHASE KW
AC wattmeter
Indicates single phase wattage of ac load
applied to phase selected by METER PHASE
SELECTOR switch in four ranges as
determined by AMMETER-WATTMETER
RANGE SELECTOR switch.
10
UNDERFREQUENCY
Spring-loaded,
Manually resets control circuit and ac loading
RESET
2-position toggle
circuit after an underfrequency cutout, provided
switch
that phase A frequency is 377 Hz or greater.
11
METER PHASE
3-position rotary switch Selects phase of ac input for indication by all
SELECTOR
meters on ac control panel except
HOURMETER.
12
AC AMPS
AC ammeter
Indicates ac loading of ac input phase selected
by METER PHASE SELECTOR switch in four
ranges as determined by AMMETER-
WATTMETER RANGE SELECTOR switch.
13
SINGLE PHASE VOLTS
AC voltmeter
Indicates line-to-neutral voltage of ac input
(L-N)
phase selected by METER PHASE SELECTOR
switch.
14
CONTROL FUSES
Three 10A fuses
Protect three phases of ac control circuits.
15
METER FUSES
Three 1A fuses
Protect PHASE SEQUENCE lights ABC and
CBA and SINGLE PHASE VOLTS (L-N)
meter.
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