Overload Prevention Control Board (Opcb) - Generac Power Systems RTSR600A3 Owner's Manual

2.5 OVERLOAD PREVENTION CONTROL
BOARD (OPCB)
The OPCB can control an air conditioner (24 VAC) directly or a sepa-
rate contactor PPM (24 VAC or 120 VAC operating coil) which can
control any load connected to it. See Figure 2.1.
The Power Management Module (PMM) is not supplied with the
transfer switch. It can be purchased separately from the manufacturer
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 supply transformer, connected to the LOAD
supply in the RTS. (Each output is limited to 1 amp) The PMM contac-
tor 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 2.1.
A grommet is provided to route Class 2 wiring through. The grommet
can be used in any knockout for NEMA 1 installations. The grommet
can only be used in the bottom knockouts for NEMA 3R installations.
Figure 2.1 — Overload Prevention Control
0 Ground
194 +12V
23 Transfer
Y wire
A/C 1 & LOAD 1
A/C 2 & LOAD 2
LOAD 3
LOAD 4
Control of Air Conditioner Load
1. Route the thermostat cable (from the furnace/thermostat to the
outdoor air conditioner unit) to the transfer switch.
2. Connect the wire to the terminal strip terminals (Air 1) on the
OPCB as shown in Figure 2.1. These are normally closed con-
tacts which open upon load shed conditions. Route thermostat
wire away from High voltage wires.
3. If required, connect the second air conditioner to the terminal
strip terminals (Air 2).
These instructions are for a typical air conditioner installation.
Control of heat pump and 2-stage air conditioners will require
special connections or the use of Power Management Modules
to control the loads.
LOAD
1
SUPPLY
T1
NEUTRAL
LOAD
2
SUPPLY
A/C 1
1
24V
LOAD 1
2
1A MAX
A/C 2
1
24V
LOAD 2
2
1A MAX
1
LOAD 3
2
1A MAX
1
4
LOAD
2
1A MAX
Contact Ratings
Air 1 & 2 24 VAC, 5.0 Amps Max
NOTE:
Supply
PMM #1
Supply
PMM #2
Coil wires
Supply
PMM #3
Supply
PMM #4
Installation
Load #1
Load #2
Load #3
Load #4
5