Operator's Manual

Operator’s Manual ASCO 336 / 337
381333-427 A ASCO Power Technologies Page 3
Automatic Control System
The 336 / 337 is an automatic control system that may start
and/or stop generators and operate the transfer switch at any
time to maintain power to the load.
Proper precautions must be taken, including tag out
/ lock out procedures, to ensure personnel safety.
Installation
The system is factory wired and tested. Installation requires
mounting, connecting service cables, and connecting generator
control and generator circuit breaker control circuits.
System installation and startup by ASCO Power
Technologies is recommended.
An experienced licensed electrician must install the system.
Supporting Foundation
The supporting foundation for the enclosure must be level and
straight. Refer to the applicable enclosure outline drawing
included with the system for all mounting details including
door opening space.
If bottom cable entry is used, the foundation must be prepared
so that the conduit stubs are located correctly. Refer to the
enclosure outline drawing for specified area and location.
Provide cable bending space and 1 inch minimum clearance to
live metal parts. When a concrete floor is poured, use
interlocking conduit spacer caps or a wood or metal template
to maintain proper conduit alignment.
Mounting
Refer to the outline and mounting diagram and mount the
transfer switch according to details and instructions shown on
the diagram. Mount it vertically to a rigid supporting
structure. Level all mounting points by using flat washers
behind the holes to avoid distortion of the transfer switch.
Protect the transfer switch from construction grit
and metal chips to prevent malfunction or
shortened life of the transfer switch.
Line Connections
Refer to the wiring diagram provided with the transfer switch.
All wiring must be made in accordance with the National
Electrical Code and local codes.
De-energize the conductors before making any line
or auxiliary circuit connections. Be sure that the
Generator 1 and Generator 2 line connections are
in proper phase rotation. Place the engine
generator starting controls in the OFF position.
Make sure engine generators are not in operation.
Testing Power Conductors
Do not connect the power conductors to the transfer switch
until they are tested. Installing power cables in conduit, cable
troughs, and ceiling-suspended hangers often requires
considerable force. The pulling of cables can damage
insulation and stretch or break the conductor’s strands. For
this reason, after the cables are pulled into position, and before
they are connected, they should be tested to verify that they
are not defective or have been damaged during installation.
Connecting Power Cables
After the power cables have been tested, connect them to the
appropriate terminal lugs (if provided) on the transfer switch
as shown on the wiring diagram provided with the transfer
switch. Make sure that the lugs are suitable for use with the
cables being installed. Be careful when stripping insulation
from the cables; avoid nicking or ringing the conductor.
Remove surface oxides from cables by cleaning with a wire
brush. When aluminum cable is used, apply joint compound
to conductors. Tighten cable lugs to the torque specified on
rating label.
DANGER
!
NOTIC
E
NOTIC
E
WARNING
!