Specifications

33 Catalog WMC-4
Electrical Data
Wiring, fuse and wire size must be in accordance
with the National Electric Code (NEC).
Figure 22, Terminal Box, One Circuit
Important: The voltage to these units must be
within ±10% of nameplate voltage and the voltage
unbalance between phases must not exceed 2%
per
NEMA MG-1, 1998 Standard.
Power Wiring
The standard power wiring connection to WMC
chillers is multi-point, i.e. a separate power supply
to each of the two circuit’s terminal box. Single-
point connection to one terminal box is available
as an option, in which case the individual circuit
breakers for each circuit are retained.
The terminal box (as shown to the right) contains
the circuit breaker/disconnect (standard on multi-
point connection, optional on single-point
connection), a line reactor, and optional radio
frequency (RF) filter.
Power wiring to compressors must be in proper
phase sequence. Motor rotation is set up for
clockwise rotation facing the lead end with phase
sequence of 1-2-3. Care must be taken that the
proper phase sequence is carried through the
starter to compressor. With the phase sequence of
1-2-3 and L1 connected to T1 and T6; L2
connected to T2 and T4; and L3 connected to T3
and T5; rotation is proper.
Table 10, WMC Electrical Connections
Standard Amp Rating
High Short Circuit Current
Rating, HSCC
Power Connection
Power Block Disconnect Power Block Disconnect
Single-point
Terminal Box
Standard Rated
Power Block
Standard Rated Molded
Case Disc. Switch
HSCC Rated
Circuit Breaker
Single-point
Each Compressor
Electric Box
Standard Rated
Circuit Breaker
Standard Rated
Circuit Breaker
Not Available
HSCC Rated
Circuit Breaker
Multi-point
Not Available
(2) Standard Rated
Circuit Breakers
Not Available
(2) HSCC Rated
Circuit Breakers
NOTES
1. Bold type combination is standard offering, all other combinations are options.
2. Circuit breakers have through-the-door disconnect switch handle.
3. When HSCC rating is included, the entire two compressor electric boxes, and single-point box if ordered, are
HSCC rated. HSCCR at 460volts is 65 kA.
Power
Entry
(3)
Trnsfm
Incoming
Lugs
120/24V
Disconnect
Switch
Trnsfm
Line
480/120V
Reactors