Thermcraft XST-3-0-36-3V - Manual (Page 41)

Installation and Operation Handbook Installation
2408 and 2404 Controller 1-11
COMMUNICATION MODULES 1 AND 2
All 2408 and 2404 controllers can be fitted with up to two plug-in communications modules.
Only one of the two modules can be for serial communications and this will normally be
installed in position COMMS 1 (although it is possible to install the serial communications
module in position COMMS 2. Serial communications may be configured for either Modbus
or EI bisynch protocol.
It is also possible to fit a PDS module in one or other of these positions.
Possible module types are shown in the table below.
Communications module 1 Terminal identity (COMMS 1)
Module type HA HB HC HD HE HF
2-wire EIA-485 serial
communications − − −
Common A (+) B (−)
EIA-232 serial
communications − − −
Common Rx Tx
4-wire EIA-485 serial
communications − A ′
(Rx+)
B ′
(Rx −)
Common
A
(Tx+)
B
(Tx −)
PDS Setpoint retransmission − − − −
Signal Common
Communications module 2 Terminal identity (COMMS 2)
Module type JD JE JF
PDS Setpoint retransmission −
Signal Common
PDS Setpoint input −
Signal Common
Table 1-3 Communication modules 1 and 2 connections