King Electric Transformer Silent Relay - Manual (Page 2)

SERIES
www.king-electric.com
King Electrical Manufacturing Company / 9131 10th Avenue South, Seattle, WA 98108 / phone 206.762.0400 / fax 206.763.7738
Basic Silent Operator components are a line-to-low voltage transformer,
a low voltage bi-metal heater, an ambient compensating bi-metal and a
normally open single pole single throw line voltage snap-action switch.
In operation a circuit is completed through the bi-metal heater as the
low voltage room thermostat closes its contacts. In approximately 45
seconds the warping action of the heater closes the line voltage snap-
action to energize the heating load. When the thermostat opens its
contacts the bi-metal heater cools for approximately 45 seconds before
the line voltage switch opens to de-energize the heating load.
USING ONE THERMOSTAT AND TWO OR MORE SILENT OPERATORS TO “SEQUENCE” LOADS
Figure 3 shows how several Level-Temp Silent Operators can be used
to “sequence on” separate heating loads. This may be accomplished
by “jumpering” the thermostat leads of the additional silent operators,
and wiring them in careful conformance to the recommended wiring
diagram. Note that only one silent operator is in the thermostat circuit.
Therefore, set the adjustable heater in thermostat at .2A, or use a
thermostat with a .2A fixed heater.
SEQUENCE OF OPERATIONS: A circuit is completed through the
bi-metal heater of the first silent operator as the contacts of the low
voltage thermostat close. In approximately 45 seconds, the line voltage
snap-switch of this operator closes, energizing heating load #1 and the
transformer primary of silent operator #2. Since the thermostat leads
of this operator are “jumpered”, its bi-metal heater immediately begins
its’ warping action. In approximately 45 seconds the line voltage switch
of operator #2 closes to energize heating load #2 and the transformer
primary of silent operator #3. This “sequence on” pattern continues
until all successive silent operators and heating loads have been
energized. When the single Level-Temp room thermostat opens its
contacts each separate heating load will be “sequenced off” in intervals
of approximately 45 seconds.
Fig. 4. Typical wiring diagram to operate two or more loads simultaneously
OPERATION
tranformer relays