Installation
Automatic Transfer Switch Owner’s Manual
7
Section 3: Installation
Introduction
This equipment has been wired and tested at the factory.
Installing the switch includes the following procedures:
•
Mounting the enclosure.
•
Connecting power source and load leads.
•
Connecting the generator start and sensing circuit.
•
Connecting any auxiliary contact (if needed).
•
Testing functions.
Mounting
Mounting dimensions for the transfer switch enclosure
are in this manual. Enclosures are typically wall-
mounted. See
.
This transfer switch is mounted in a UL type 3R
enclosure. It can be mounted outside or inside and
should be based on the layout of installation,
convenience and proximity to the utility supply and load
center.
Install the transfer switch as close as possible to the
electrical loads that are to be connected to it. Mount the
switch vertically to a rigid supporting structure. To prevent
switch distortion, level all mounting points. If necessary,
use washers behind mounting holes to level the unit.
Connecting Power Source and Load Lines
Installation and interconnection diagrams are provided in
this manual.
NOTE:
All installations must comply with national, state
and local codes. It is the responsibility of the installer to
perform an installation that will pass the final electrical
inspection.
The utility supply connection is made at the utility service
disconnect circuit breaker terminals. The generator and
customer load connections are made at the transfer
switch mechanism, inside the switch enclosure.
Conductor sizes must be adequate to handle the
maximum current to which they will be subjected, based
on the American Wire Gauge (AWG) 167°F (75°C)
column of tables, charts, etc. used to size conductors.
The installation must comply fully with all applicable
codes, standards and regulations.
All power cables can enter the enclosure through the
knockouts provided. If not using the knockouts, conduit
entry into the enclosure above the level of uninsulated
live parts shall use fittings listed for use in wet locations
to maintain the Type 3R rating. Conduits should be
arranged to provide separation between the Utility and
Generator supply conductors inside the enclosure.
NOTE:
If aluminum conductors are used, apply corrosion
inhibitor to conductors. After tightening terminal lugs,
carefully wipe away any excess corrosion inhibitor.
Tighten terminal lugs to the torque values as noted on the
decal located on the inside of the door. After tightening
terminal lugs, carefully wipe away any excess corrosion
inhibitor.
Connect power source and load conductors to clearly
marked terminal lugs on transfer mechanism as follows:
1.
Connect utility (normal) power source cables to
utility service disconnect circuit breaker.
2.
Connect the generator (standby) source power
cables to transfer switch terminals E1, E2., and E3
3.
Connect customer LOAD leads to switch terminals
T1, T2, and T3.
Connecting Start Circuit Wires
Control system interconnections may consist of N1, N2,
and T1, and leads 23 and 194. The generator control
wiring is a Class 1 signaling circuit. Reference the
Installation Manual of the specific generator for wiring
connection details. Recommended wire gauge sizes for
this wiring depends on the length of the wire, as
recommended in the following chart:
Exception:
Conductors of AC and DC circuits, rated
1000 volts nominal or less, shall be permitted to occupy
the same equipment, cable, or conduit. All conductors
shall have an insulation rating equal to at least the
maximum circuit voltage applied to any conductor within
the equipment, cable, or conduit. See NEC 300.3(C)(1).
NOTE:
An RTS series transfer switch without a T1/
Fused connection must use a 120VAC protected circuit
from the panel board to power the battery charge circuit
(dedicated 15/20 amp circuit).
(000119)
Equipment malfunction. Installing a dirty or damaged
transfer switch will cause equipment malfunction and
will result in death or serious injury.
DANGER
Electrocution. Turn utility and emergency
power supplies to OFF before connecting
power source and load lines. Failure to do so
will result in death or serious injury.
(000116)
DANGER
Maximum Wire Length
Recommended Wire Size
1–115 ft (1–35 m)
No. 18 AWG
116–185 ft (36–56 m)
No. 16 AWG
186–295 ft (57–89 m)
No. 14 AWG
296–460 ft (90–140 m)
No. 12 AWG
(000120)
CAUTION
Equipment damage. Verify all conductors are
tightened to the factory specified torque value.
Failure to do so could result in damage
to the switch base.
