Connecting Start Circuit Wires; Overload Prevention Control Board (Opcb) - Generac RTSR400A3 El Manual Del Propietario

Installation
Figure 2.1 — Typical 2-Pole Transfer Mechanism (400
Amp Shown)
Solderless, screw-type terminal lugs are standard.
The conductor size range is as follows:
Switch Rating
400A
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.
Before connecting wiring cables to terminals, remove any surface
oxides from the cable ends with a wire brush. All power cables
should enter the switch next to transfer mechanism terminals.
If ALUMINUM conductors are used, apply corrosion inhibitor to
conductors. 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.
All power cables should enter the switch next to the transfer
mechanism terminals.
Use a torque wrench to tighten the conductors,

being sure not to overtighten, or damage to the
switch base could occur. If undertightened, a
loose connection would result, causing excess
heat which could damage the switch base.
4
Wire Range
(1) #4-600 MCM or
(2) 1/0-250 MCM
Connect power source load conductors to clearly marked transfer
mechanism terminal lugs as follows:
1. Connect UTILITY (NORMAL) power source cables to switch
terminals N1, N2.
2. Connect EMERGENCY (STANDBY) source power cables to
transfer switch terminals E1, E2.
3. Connect customer LOAD leads to switch terminals T1, T2.
4. Connect neutral conductors of UTILITY, EMERGENCY and
customer LOAD to the neutral block.
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 in the Electrical Data section
consist of UTILITY 1 (N1), 2 (N2), Load (T1) and leads 23 and
194. Recommended wire gauge sizes for this wiring depends on
the length of the wire, as recommended below:
MAXIMUM WIRE LENGTH
1-115 ft (1-35m)
116-185 ft (36-56m)
186-295 ft (57-89m)
296-460 ft (90-140m)
2.5 OVERLOAD PREVENTION CONTROL
BOARD (OPCB)
The OPCB can control an air conditioner (24 VAC) directly or a
separate contactor PPM (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 manufac-
turer. for use with the Overload Prevention Control Board (OPCB)
mounted in the transfer switch. The OPCB is designed and con-
nected to power the PMM contactor operating coil. The OPCB is
supplied by a 24 VAC supply, class 2 power supply 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.
RECOMMENDED WIRE
SIZE
No. 18 AWG.
No. 16 AWG.
No. 14 AWG.
No. 12 AWG.