Installation Instructions
4
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.
2.3 CONNECTING POWER SOURCE
AND LOAD LINES
Make sure to turn OFF both the UTILITY
(NORMAL) and GENERATOR (STANDBY)
power supplies before trying to connect power
source and load lines to the transfer switch.
Supply voltages are extremely high and dan-
gerous. Contact with such high voltage power
supply lines causes extremely hazardous, pos-
sibly lethal, electrical shock.
Wiring diagrams and electrical schematics 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 DIS-
CONNECT 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 cur-
rent to which they will be subjected, based on the 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 must enter the enclosure through the knockouts
provided. If not using the knockouts, conduit entry into the enclo-
sure must be at or below knockouts to maintain the Type 3R rating.
Conduits should be arranged to provide separation between the
Utility and Generator supply conductors inside the enclosure.
Before connecting wiring cables to terminals, remove any surface
oxides from the cable ends with a wire brush. If ALUMINUM con-
ductors are used, apply corrosion inhibitor to conductors. Tighten
terminal lugs to the torque values on "Utility Service Disconnect
Circuit Breaker", and on the decal located on the inside of the door.
After tightening terminal lugs, carefully wipe away any excess cor-
rosion inhibitor.
Use a torque wrench to tighten the conductors,
being sure not to overtighten, or damage to
the switch base could occur. If not tightened
enough, a loose connection would result,
causing excess heat which could damage the
switch base.
Connect power source load conductors to clearly marked transfer
mechanism terminal lugs as follows
1. Connect UTILITY (NORMAL) power source cables to UTILITY
SERVICE DISCONNECT circuit breaker.
2. Connect the GENERATOR (STANDBY) source power cables to
switch terminals E1, E2.
3. Connect customer LOAD leads to switch terminals T1, T2.
Conductors must be properly supported, of approved insulative
qualities, protected by approved conduit, and of the correct wire
gauge size in accordance with applicable codes.
Be sure to maintain proper electrical clearance between live metal
parts and grounded metal. Allow at least 1/2 inch for 100-400
amp circuits.
2.4 CONNECTING START CIRCUIT
WIRES
Control system interconnections (Electrical Data section) consist
of UTILITY 1 (N1), UTILITY 2 (N2) and LOAD (T1), and leads 23, 0
and 194. Recommended wire gauge sizes for this wiring depends
on the length of the wire, as recommended in the following chart:
MAXIMUM WIRE LENGTH
RECOMMENDED WIRE
SIZE
460 feet (140m) No. 18 AWG.
461 to 730 feet (223m) No. 16 AWG.
731 to 1,160 feet (354m) No. 14 AWG.
1,161 to 1,850 feet (565m) No. 12 AWG.
2.5 OVERLOAD PREVENTION
CONTROL BOARD (OPCB)
The OPCB can control an air conditioner (24 Vac) directly or a
separate contactor (24 Vac or 120 Vac operating coil) which can
control any load connected to it. See Figure 2.2.
The Power Management Module (PMM) is not supplied with
the transfer switch. It can be purchased separately from the
manufacturer. The PMM is for use with the Overload Prevention
Control Board (OPCB) mounted in the transfer switch. The OPCB
is designed and connected to power the PMM contactor operating
coil. The OPCB is supplied by a 24 Vac supply, class 2 power sup-
ply transformer, connected to the LOAD supply in the RTS. (Each
output is limited to 1 amp) The PMM contactor coil connections
are made at the OPCB terminal strip.
Connect the PMM contactor coil to OPCB contactor terminals (1,
2, 3 or 4). The selection of contactor terminal used will depend on
the priority of the load being controlled. This is a 24 Vac circuit and
wiring methods for class 2 should be used. Use ¼” quick connect
terminals to make the contactor coil connections on the PMM. See
Figure 2.3.
A grommet is provided to route Class 2 wiring through. The grom-
met can be used in any knockout for NEMA 1 installations. The
grommet can only be used in the bottom knockouts for NEMA 3R
installations.
Installation