Operating instructions

IMM AGSB-60 39
Electrical Data Notes
1. Allowable voltage limits
Unit nameplate 460V/60Hz/3Ph: 414V to 506V
Unit nameplate 575V/60Hz/3Ph: 518V to 632V
2. Unit wire size ampacity (MCA) is equal to 125% of the largest compressor-motor RLA plus 100% of
RLA of all other loads in the circuit.
3. Single point power supply requires a single disconnect to supply electrical power to the unit. This
power must be fused.
4. All field wiring to unit power block or optional nonfused disconnect switch must be copper.
5. External disconnect switch(s) or HACR breakers must be field supplied.
Note: A non-fused disconnect switch in the cabinet is available as an option for single-point or multi-
point power connections.
6. All wiring must installed as NEC Class 1 wiring system with conductor rated 600 volts and be done in
accordance with applicable local and national codes.
7. Recommended time delay fuse size or HACR circuit breakers is equal to 150% of the largest
compressor motor RLA plus 100% of remaining compressor RLAs and the sum of condenser fan
FLAs.
8. Maximum time delay fuse size or HACR circuit breakers is equal to 225% of the largest compressor-
motor RLA plus 100% of remaining compressor RLAs and the sum of condenser fan FLAs.
9. If 1) the evaporator heater is to be powered during winter shutdown and 2) it is desired to disconnect
460/575 volt power to the unit, then the unit-mounted 3 KVA control transformer can be unwired and
a field 115-volt, 30-amp power source wired to terminals TB1-1 and TB1-2. The MicroTech II
control must be powered in order for the heaters to work.
Power Limitations:
1. Voltage within ± 10 percent of nameplate rating.
2. Voltage unbalance not to exceed 2% with a resultant current unbalance of 6 to 10 times the voltage
unbalance per NEMA MG-1, 1998 Standard.
Optional Protocol Selectability Connection
Optional Protocol Selectability BAS interfaces. The locations and interconnection requirements for the
various standard protocols are found in their respective installation manuals, obtainable from the local
McQuay sales office and also shipped with each unit:
Modbus IM 743 L
ONWORKS IM 735 BACnet IM 736