GE Industrial Solutions ZBTSCTH SERIES 100 - 4000 AMPS User Manual
Page 5
ZBTSCTH Operation and Maintenance Manual (46R-7000)
Zenith Controls, Inc.
3
SECTION I - INSTALLATION
(Continued)
4. POWER CONNECTIONS
Zenith transfer switches are supplied with UL
listed solderless screw type terminals as
standard for the Normal, Emergency, and Load
power connections. Table 1 lists the number and
sizes of the cable lugs supplied as standard for
each switch amp rating.
Connect the Normal, Emergency, and Load
conductors to the clearly marked terminals on
the transfer switch. Remove surface oxides from
cables by cleaning with a wire brush. Verify that
Tightening Torque for Lugs
Socket Size
Torque
Across Flats
Lb.-In.
Lb.-Ft.
1/8
45
4
5/32
100
8
3/16
120
10
7/32
150
12
1/4
200
17
5/16
275
23
3/8
375
31
1/2
500
42
9/16
600
50
Tightening Torque for Bus Bars
Bolt Size
Torque Bolt (Grade 5)
Lb.-In.
Lb.-Ft.
1/4-20
72
6
5/16-18
132
11
3/8-16
300
25
1/2-13
720
60
Table 2
Table 3
Table 1
Screw Type Terminals for External Power Connections
Normal, Emergency & Load Terminals
Fully Rated Neutral Bar (When Required)
Switch Size
(Amps)
Cable Per Pole
Range of Wire Sizes
Number of Cables
Number of Cables
100
1
#14 to 1/0 AWG
3
#14 to 1/0 AWG
150
1
#8 to 3/0 AWG
3
#6 AWG to 300 MCM
225
1
#6 AWG to 250 MCM
3
#6 AWG to 300 MCM
260
1
#6 AWG to 350 MCM
3
#6 AWG to 300 MCM
400
1
#4 AWG to 600 MCM
4
#6 AWG to 300 MCM
600
2
#2 AWG to 600 MCM
8
#2 AWG to 600 MCM
800
1000
1200
4
#2 AWG to 600 MCM
12
#2 AWG to 600 MCM
1600
2000
3000
4000
Line and load terminals are located in
rear and arranged for bus bar
connection.
12
3/0 AWG to 750 MCM
all connections are correct before tightening
the lugs. All cable lug connections must be
tightened to the proper torque values as shown
in Table 2.
Do not run cables or wiring behind front-
connected transfer switches.
In cases where the Normal, Emergency, and
Load connections are made to a rear connected
bus bar, a compression washer, flat washer, and
a minimum grade 5 bolt must be used and
torqued to the values in Table 3.