CONNECTIONS – ELECTRICAL
32
RS485 Communication Cable Connection Procedure
To connect a cable for RS485 communication
to the water heater:
1.
Undo the screw securing the Sunshield
from the Master Controller Module, and set
the Sunshield and screw aside.
2.
Undo the four screws securing the cover
plate to the front of the User Interface
Module, and set the cover plate and
screws aside.
3.
Undo the two screws securing the cable
clamp, and set the cable clamp and screws
aside.
4.
Remove the black rubber grommet and
slide over the end of the cable.
5.
Remove the cable plug from the socket
located on the upper right hand side of the
cavity in the User Interface Module.
6.
Connect the cable wires to the cable plug
ensuring the correct coloured wires are
connected to the connections marked A+,
B+, G.
Note:
It is important to ensure each colour
wire is connected to the equivalent
connection on the plug that connects to the
external control device.
7.
Connect the cable plug into the socket
securely locking into position.
8.
Position the cable, ensuring the cable
insulation is seated in the clamp mould.
9.
Ensure the black rubber grommet is in
position.
10.
Refit the cable clamp, securing into
position with its two screws.
11.
Refit the cover plate, securing into position
with its four screws.
12.
Refit the Sunshield to the Master Controller
Module, securing with its screw.
Note:
The Master Controller Module has a
termination resistor fitted for RS485 multi-drop
applications. The terminator resistor can be
removed from the circuit by the removal of the
jumper, which is located adjacent to the cable
socket connection. The jumper should only be
removed in cases where the water heater is
part of a multi-drop RS485 installation and the
water heater is not the final node on the RS485
drop.
Cable Connection for RS485 Communication
cover plate and screws
cable clamp
and screws
grommet
cable plug for
RS485 connection
cable for RS485
communication
cable
socket
connection
jumper
Master Controller
Module
Sunshield
User Interface
Module
