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2 Wiring
Refer to the wiring diagrams in Section 7.
Note:
Low voltage wiring must enter the enclosure
above the power relays to ensure separation of
circuits per NEC requirements.
Route the low
voltage wiring to avoid contact with: 1) line
voltage field wiring to the relays; 2) live parts of
the relays; and 3) and all insulated lead wires to
the relays – contacts and coil.
2.1 Power Relay Load Connections
The customer can either wire directly into terminal
blocks in the Load Control Module or utilize a pre-landed
wire harness that connects all of the power relays to the
distribution panel and the respective branch circuit
breakers.
The pre-wired harness contains seventeen #8 AWG
stranded wires inserted into a two foot section of
liquid-tight flexible conduit. Each wire is 90 inches long
and has one end terminated in a ring terminal. Wires are
marked per the designations shown in Figure 9. The
ground wire is green. Appropriate elbows and fittings
connect the conduit to the Load Control Module
enclosure and the customer’s electrical distribution
enclosure.
2.2 HVAC Connections
The air conditioner control scheme involves splicing into
the existing building low voltage wiring from the
thermostat to the air conditioner/furnace. In a typical
four wire scheme, connect the cooling wire (Y) in series
to the respective terminal block on the LCM. See the
wiring diagrams in Section 7.
Connect the more
important air conditioner to HVAC A. Connect the less
important air conditioner, if applicable, to HVAC B.
Use 18-14 AWG solid or stranded wires from the
thermostat/HVAC system to the 6-position terminal
block on the LCM circuit board. See the wiring diagrams
in Section 7 for connections.
2.3 120 VAC Power Supply
Connect 120 VAC power to the terminal block labeled
120 VAC in the lower left corner of the LCM enclosure.
The circuit must be protected by a 15 amp fuse or circuit
breaker (not provided). See Figure 28 and the wiring
diagrams in Section 7.
2.4 Generator Controller Interface
Connection
Connect a twisted-pair communication line from P10 on
the LCM circuit board to the DC2/RDC2 controller. One
pair carries the communication signal, the other pair
supplies DC voltage to the board.
Use Belden cable #9402 or equivalent 20 AWG
shielded,
twisted-pair
cable
from
the
generator
controller to the four-position terminal block on the LCM.
The terminal block is rated for 5 A at 300 VAC. See
Figure 12 for cable specifications.
Controller Communication Interconnection
Pin
Designation
Description
1
A
RBUS Communi
2
B
RBUS Communication -
3
PWR
12VDC Power +
4
COM
12VDC Power -
RBUS: RS-485 proprietary communication.
Figure 11
Controller Interface Connections
If a transfer switch other than the Model RXT is used, the
transfer switch does not connect to the RBUS
communication circuit. See Figure 14. Connect engine
start leads 3 and 4 as shown, and be sure to install the
current transformer on the emergency source lines and
connect it to the LCM.
See Figure 13 through Figure 18 for connection options
with up to three accessory modules.
Accessory
modules can include one Model RXT transfer switch,
one programmable interface module (PIM), and/or one
load control module (LCM).
See Figure 12 for the maximum total cable length with 1,
2, or 3 accessory modules per cable run.
D
Use Belden #9402 (4-conductor) or equivalent 20
AWG shielded, twisted-pair cable. Note the shield
connections shown in Figure 13.
D
If longer cable runs are required, #12--14 AWG wire
can be used for the COM and PWR connections. The
maximum total cable length is the value shown for
#12 or #14 AWG wire in Figure 12.
