IOM 1206-1
19
Electrical Data
Electrical Data
Electrical Data Notes
Notes for Unit Amp Draw:
1
Compressor RLA values are for wire sizing purposes
only. Normal operating current draw at rated capacity
may be less than the RLA value.
Notes for Electrical Data Single- and Multi-Point
1
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.
2
The control transformer is furnished and no separate
115V power is required. For both single- and multi-point
power connections, the control transformer is in circuit
#1 with control power wired from there to circuit #2. In
multi-point power, disconnecting power to circuit #1
disconnects control power to the unit.
3
Wire sizing amps is 15 amps if a separate 115V power
supply is used for the control circuit.
4
Recommended power lead wire sizes for 3 conductors
per conduit are based on 100% conductor ampacity in
accordance with NEC. Voltage drop has not been
included. It is recommended that power leads be kept
short. All terminal block connections must be made with
copper (type THW) wire and aluminum wire.
5
Recommended Fuse Sizes are selected at approximately
175% of the largest compressor RLA, plus 100% of all
other loads in the circuit.
6
Maximum Fuse or breaker size is equal to 225% of the
largest compressor RLA, plus 100% of all other loads.
7
The recommended power wire sizes are based on an
ambient temperature of 86°F (30°C). Ampacity
correction factors must be applied for other ambient
temperatures. Refer to the NEC Handbook.
8
Must be electrically grounded according to national and
local electrical codes.
Notes for Wiring Data
1
Single-point power supply requires a single disconnect to
supply electrical power to the unit. This power supply
must either be fused or use a circuit breaker.
2
Power wiring connections to the chiller may be done
with either copper or aluminum wiring. Wire should be
sized per NEC and/or local codes. Wire sizing and wire
count must fit in the power connection lug sizing starting
on
page 22
.
3
Aluminum wire shall be installed in accordance with
NECA/AA 104-2012,
Standard for Installing Aluminum
Building Wire and Cable
(ANSI).
4
All field wire size values given in table apply to 75°C
rated wire per NEC.
Voltage Limitations:
1
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, 2009 Standard Rev. 1-2010.
Table 16: HSCCR Panel Rating
Table 17: Standard Panel Rating
Circuit Breakers
Factory installed compressor circuit breakers are standard on
units with single point power supply only. This option provides
compressor short circuit protection and makes servicing easier
Electrical Control Center
Operating and equipment protection controls and motor
starting components are separately housed in a centrally
located, weather resistant control panel with hinged and tool-
locked doors. In addition to the MicroTech III controller
described in the next sections, the following components are
housed in the panel:
• Power terminal blocks, multi-point connection standard
• Control, input, and output terminal block
• Control transformer
• Optional disconnect switch (through-the-door handle)
• Compressor motor inherent thermal and overload protec-
tion is standard
• Optional phase voltage monitor with under/over voltage
and phase reversal protection
• Fan contactors with short circuit protective devices.
• Optional ground fault protection
• FanTrol fan staging head pressure control system
• Power connections are per the following table
Power Connections
Table 18: Power Connection Availability
Definitions:
1
Power Block: An electrical device to directly accept field
wiring without any disconnecting means.
2
Disconnect Switch: A molded case switch that accepts
field wiring and disconnects main power to the entire
unit or each main power supply if the multi-point power
supply option is selected. This option does not provide
overcurrent protection.
3
Compressor Circuit Breakers: A manually reset circuit
breaker for each compressor, providing compressor only
short circuit protection and located ahead of contactor.
4
Control Panel High Short Circuit Current Rating:
(Previously "withstand rating"). The entire control panel
is designed for short circuit current rating in
Table 16
. In
the event of a short circuit, the damage is contained
within the control panel enclosure.
AGZ-E Model Size
208V-230V
380V-460V
575V
030-070
65kA
65kA
25kA
AGZ-E Model Size
208V
230V
380V
460V
575V
030-070
5kA
5kA
5kA
5kA
5kA
Power Connection
Power
Block
Disc. Swt.
Comp Circuit
Breakers
Panel
HSCCR
AGZ030E-070E
Optional Single Point
Std
Opt.
Std
Opt
AGZ030E-070E
Standard Multi-Point
Std
Opt.
Not Avail.
Opt.
