A
If disconnect box is mounted to corner post, be careful not to drill any screws into the condenser coil.
Routing Through Bottom of Unit Ð If wiring is brought in through bottom of unit, use
Use strain relief going into control box through
Install conduit connector in unit basepan or side panel open- ings provided. Route power and ground lines through con- nector to connections in unit control box as shown on unit wiring diagram and Fig. 13.
Routing Through Side of Unit Ð Route power wiring in
Use
Bring
After wiring is in control box, make connection to proper terminals on terminal blocks (see Field Control Wiring sec- tion on this page).
IMPORTANT: THE VAV (variable air volume) units incorporate VFD (variable frequency drives) which gen- erate, use, and can radiate radio frequency energy. If units are not installed and used in accordance with these instructions, they may cause radio interference. They have been tested and found to comply with limits of a Class A computing device as de®ned by FCC (Federal Communications Commission) regulations, Subpart J of Part 15, which are designed to provide reasonable protection against such interference when operated in a commercial environment.
The unit must be electrically grounded in accordance with local codes and NEC ANSI/NFPA 70 (National Fire Protection Association).
Operating voltage to compressor must be within voltage range indicated on unit nameplate. On
Use the formula in Table 4 to determine the percentage of voltage imbalance.
IMPORTANT: If the supply voltage phase imbalance is more than 2%, contact your local electric utility com- pany immediately.
Unit failure as a result of operation on improper line volt- age or excessive phase imbalance constitutes abuse and may cause damage to electrical components.
On
1.Remove cap from red (208-v) wire.
2.Remove cap from spliced orange
3.Cap orange wire.
4.Splice red wire and black unit power wire. Cap wires.
IMPORTANT: Be certain unused wires are capped. Failure to do so may damage the transformers.
FIELD CONTROL WIRING Ð Install either a Carrier- approved accessory thermostat or a CCN (Carrier Comfort Network) compatible temperature sensor. Thermostats are used on CV (constant volume) units only. Control box diagrams are shown in Fig. 14 and 15.
Thermostat Wiring (CV Only) Ð Install a
Route thermostat cable or equivalent single leads of col- ored wire from subbase terminals to
NOTE: For wire runs up to 50 ft, use no. 18 AWG (Ameri- can Wire Gage) insulated wire (35 C minimum). For 50 to 75 ft, use no. 16 AWG insulated wire (35 C minimum). For over 75 ft, use no. 14 AWG insulated wire (35 C minimum). All wire larger than no. 18 AWG cannot be directly con- nected to the thermostat and will require a junction box and splice at the thermostat.
Set heat anticipators settings to 0.1 for all voltages. Set- tings may be changed slightly to provide a greater degree of comfort for a particular installation.
Sensor Wiring (CV or VAV) Ð The temperature sensor is wired into the unit control board. See Fig. 17.
The unit is controlled with a T55, T56 (CV only), or T57 zone sensor. Terminal TH on the sensor is connected to T1 of the base module board. Terminal COM on the sensor is connected to T2 on the base module board. If a T56 set point override sensor is used, the override connection SW on the sensor is connected to T3 on the base module board.
VAV units using Version 1.0 of the unit control software may operate without a space temperature sensor during oc- cupied schedules, but unit will not provide unoccupied heat- ing or cooling.
VAV Units Ð VAV units require a
Remote Field Control (Units Running Version 1.0 of Unit Control Software) Ð A switch closure across terminals R
and Y1 on
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