HIGH-VOLTAGE Connections

Duct Covers

A05301

Fig. 11 - 50CR with Duct Covers On

1” (25mm) MIN.

TRAP

OUTLET

2” (50mm) MIN.

C99013

Fig. 12 - Condensate Trap

Step 7—Install Electrical Connections

!WARNING

ELECTRICAL SHOCK HAZARD

Failure to follow this warning could result in personal injury or death.

The unit cabinet must have an uninterrupted, unbroken electrical ground to minimize the possibility of personal injury if an electrical fault should occur. This ground may consist of an electrical wire connected to the unit ground screw in the control compartment, or conduit approved for electrical ground when installed in accordance with NEC, ANSI/NFPA American National Standards Institute/National Fire Protection Association (latest edition) (in Canada, Canadian Electrical Code CSA C22.1) and local electrical codes.

The unit must have a separate electrical service with a field-supplied, waterproof disconnect switch mounted at, or within sight from the unit. Refer to the unit rating plate, NEC and local codes for maximum fuse/circuit breaker size and minimum circuit amps (ampacity) for wire sizing (See Table 2 for electrical data).

The field-supplied disconnect may be mounted on the unit over the high-voltage inlet hole (See Fig. 6 and 7).

If the unit has an electric heater, a second disconnect may be required. Consult the Installation, Start-Up, and Service Instructions provided with the accessory for electrical service connections.

Operation of unit on improper line voltage constitutes abuse and may cause unit damage that could affect warranty.

!CAUTION

UNIT COMPONENT DAMAGE HAZARD

Failure to follow this caution may result in damage to the unit being installed.

1.Make all electrical connections in accordance with NEC ANSI/NFPA (latest edition) and local electrical codes governing such wiring. In Canada, all electrical connections must be in accordance with CSA standard C22.1 Canadian Electrical Code Part 1 and applicable local codes. Refer to unit wiring diagram.

2.Use only copper conductor for connections between field-supplied electrical disconnect switch and unit. DO NOT USE ALUMINUM WIRE.

3.Be sure that high-voltage power to unit is within operating voltage range indicated on unit rating plate. On 3-phase units, ensure phases are balanced within 2 percent. Consult local power company for correction of improper voltage and/or phase imbalance.

4.Insulate low-voltage wires for highest voltage contained within conduit when low-voltage control wires are in same conduit as high-voltage wires.

5.Do not damage internal components when drilling through any panel to mount electrical hardware, conduit, etc.

ROUTING POWER LEADS INTO UNIT

Use only copper wire between disconnect and unit. The high voltage leads should be in a conduit until they enter the duct panel; conduit termination at the duct panel must be watertight. Run the high-voltage leads through the power entry knockout on the power entry side panel. See Fig. 6 and 7 for location and size. For single-phase units, connect leads to the black and yellow wires ; for 3-phase units, connect the leads to the black, yellow, and blue wires.

CONNECTING GROUND LEAD TO GROUND SCREW

Connect the ground lead to the chassis using the ground screw in the wiring splice box (See Fig. 14 and 17).

ROUTING CONTROL POWER WIRES

For detailed instruction on the low voltage connections to the User Interface (UI), refer to the UI installation guide.

Form a drip-loop with the control leads before routing them into the unit. Route the low voltage control leads through grommeted, low-voltage hole provided into unit (See Fig. 6 and 7). Connect user interface leads to unit control power leads as shown in Fig. 14.

The unit transformer supplies 24-v power for complete system including accessory electrical heater. A fuse is provided in the 24-v circuit on the control board (See Fig. 19); see the caution label on the transformer. Transformer is factory wired for 230-v operation. If supply voltage is 208-v, rewire transformer primary as described in Special Procedures for 208-v Operation section.