device to the ST8. Wiring
and Slave Relay shown for clarity only.
The Figures below show typical customer switch wiring for the ST8.
Switch wiring should be run separately from other wires; DO NOT
route switch wires with AC power wires since voltages, that may
be induced into the switch wires, may exceed rating and cause
damage to circuits or cause false trips.
Figure 1 shows the wiring for a normally open (N.O.) SWICH-
GAGE
®
connected between terminal B and the negative power input.
A metal jumper is connected between A and B. When the SWICH-
GAGE
®
closes the shutdown/alarm circuit will be initiated.
Figure 2 shows the wiring for a normally closed (N.C.) switch
connected to input terminals A and B. The factory installed
metal link must be removed to use this wiring. When the switch
opens the shutdown/alarm will be initiated.
Figure 3 shows the wiring for a N.O. SWICHGAGE
®
which is the
same as Figure 1 except two wires are run from terminals A and B to
the SWICHGAGE
®
. This Closed Loop™ wiring circuit monitors the
wires as well as the switch. If the circuit is opened due to a loose
connection or broken wire or the SWICHGAGE
®
closes, the shut-
down/alarm circuit will be initiated.
Figure 4 shows the ST8 internal SPDT relay in the “run” or operat-
ing mode.
Typical Wiring
Below is a typical wiring diagram for the ST8 TATTLETALE
®
.
