Description
3
Control Panel Arrangement
See Figure 3.
1.
Input circuit breakers, 8 ampere thermal trip, manual
reset. One circuit breaker is installed in each line of the
incoming line cord. The circuit includes an air core
current limiting reactor permanently included in each line
to limit the available short circuit current. In addition to
the current limiting reactors and circuit breaker, the test
set includes static overcurrent and ground fault interrupt
circuitry.
2.
On/Off Switch. This switch controls the input power to
the test set control circuit. This switch must be ON for the
test set to operate with either the internal phase
controlled current source or with an external current
source.
3.
Internal/External Power Selector Switch. This switch
selects the current source for the test current. In the
INTERNAL position the test current is controlled by the
built in phase-controlled current source. In the EXTER-
NAL position the test current is controlled by an external
variable transformer (not supplied with the test set). The
output of the EXTERNAL transformer must be con-
nected to the two binding posts labeled EXTERNAL
POWER INPUT. The ON/OFF switch must be ON for the
test set ammeter, timer and control relays to operate.
The test current is then controlled by adjusting the
external variable transformer; otherwise the operation of
the test set is the
