Installation Instructions
2
• Never work on this equipment while physically or mentally
fatigued.
• Keep the transfer switch enclosure door closed and bolted at all
times. Only qualified personnel should be permitted access to
the switch interior.
• In case of an accident caused by electric shock, immediately
shut down the source of electrical power. If this is not possible,
attempt to free the victim from the live conductor but AVOID
DIRECT CONTACT WITH THE VICTIM. Use a nonconducting
implement, such as a dry rope or board, to free the victim from
the live conductor. If the victim is unconscious, apply first aid
and get immediate medical help.
• When an automatic transfer switch is installed for a standby
generator set, the generator engine may crank and start at
any time without warning. To avoid possible injury that might
be caused by such sudden start-ups, the system’s automatic
start circuit must be disabled before working on or around the
generator or transfer switch. Then place a “DO NOT OPERATE”
tag on the transfer switch and on the generator. Remove the
Negative (Neg) or (–) battery cable.
1.1 INTRODUCTION
This manual has been prepared especially for the purpose of famil-
iarizing personnel with the design, application, installation, opera-
tion and servicing of the applicable equipment. Read the manual
carefully and comply with all instructions. This will help to prevent
accidents or damage to equipment that might otherwise be caused
by carelessness, incorrect application or improper procedures.
Every effort has been expended to make sure that the contents
of this manual are both accurate and current. The manufacturer,
however, reserves the right to change, alter or otherwise improve
the product at any time without prior notice.
1.2 UNPACKING
Carefully unpack the transfer switch. Inspect closely for any dam-
age that might have occurred during shipment. The purchaser must
file with the carrier any claims for loss or damage incurred while in
transit.
Check that all packing material is completely removed from the
switch prior to installation.
1.3 EQUIPMENT DESCRIPTION
The automatic transfer switch is used for transferring electrical
load from a UTILITY (NORMAL) power source to a GENERATOR
(STANDBY) power source. Such a transfer of electrical loads
occurs automatically when the UTILITY power source has failed or
is substantially reduced and the GENERATOR source voltage and
frequency have reached an acceptable level. The transfer switch
prevents electrical feedback between two different power sources
(such as the UTILITY and GENERATOR sources) and, for that
reason, codes require it in all standby electric system installations.
The transfer switch consists of a transfer mechanism, UTILITY
SERVICE DISCONNECT circuit breaker, a relay control, fuses, ter-
minal strip, and fuse holder for connection of sensing wires.
This transfer switch is suitable for use as service equipment.
1.3.1 TRANSFER SWITCH MECHANISM
These switches (Figure 1.1) are used with a single-phase system,
when the single-phase NEUTRAL line is to be connected to a
Neutral Lug and is not to be switched.
Solderless, screw-type terminal lugs are standard.
Switch Rating Wire Range
300/400A (1) #4-600 MCM or
(2) 1/0-250 MCM
This transfer switch is suitable for control of motors, electric dis-
charge lamps, tungsten filament and electric heating equipment
where the sum of motor full load ampere ratings and the ampere
ratings of other loads do not exceed the ampere rating of the
switch and the tungsten load does not exceed 30 percent of the
switch rating.
This UL listed transfer switch is for use in optional standby sys-
tems only (NEC article 702).
This transfer switch is suitable for use on a circuit capable of
18,000 rms symmetrical amperes, 240 VAC maximum.
Figure 1.1 — Typical ATS Transfer Mechanism
1.3.2 UTILITY SERVICE CIRCUIT BREAKER
The utility service circuit breaker for the 300/400 amp models are:
• Generac, 300/400AF
• 120/240VAC, 300/400A
• 50/60 Hertz
• Wire range: (1) #4-600 MCM or (2) 1/0-250 MCM
• The conductor tightening torque is 375 in-lbs.
General Information










