3-8 l Installation
Connecting the Power on modelsHTC 180 and 270
The electrical connection consists of bringing power into the control center and
wiring the heater power from the control center to the heater assembly. The incom-
ing power should match the rated nameplate power required on the serial tag on the
control center. This power should be clean and have a voltage variation of no more
than +/- 5% of the nameplate voltage. Unless the actual voltage is equal to the
nameplate voltage,the actual kW output of the HTC will vary slightly. The output
varies with the square of the voltage difference.
CAUTION: Always disconnect and lock out the main power sources before mak-
ing electrical connections. Electrical connections should be made only by quali-
fied personnel.
CAUTION: Check the disconnect with a volt meter to insure that the power is off.
1Disconnect and lock out the main power sources before making electrical
connections. Electrical connections should be made only by qualified personnel.
2Turn the disconnect dial on the control center door to the Off or “O”posi-
tion. Turn the captive screw, and swing the control center door open.
3
Insert the main power
cable through a knockout in the side of the control center.
Secure the power cable with a rubber compression fitting or strain relief or use
conduit. Verify that the incoming power is securely attached to the control center
and there is no strain on the incoming power.
4
Connect the power wires
to the three terminals at the top of the power disconnect
holder.
5Connect the ground wireto the ground lug.
Note:The connection between the heater and control center should be made with
properly sized conductors and properly protected with appropriate conduit (cus-
tomer supplied). The routing should be neat and away from potential mechanical
damage. The terminations should be landed on the terminals in the control center
and heater junction area. These terminations should be regularly checked to pre-
vent loosening and shorting to ground.
✐
IMPORTANT: Always refer
to the wiring diagrams that
came with your heater
before making electrical
connections.
ON
O OFF