AERCO Control System (ACS)
CHAPTER 2
: ACS Installation
11/22/2017
AERCO International, Inc.
•
100 Oritani Dr.
•
Blauvelt, New York 10913
Page 23 of 139
OMM-0081_0F
Phone: 800-526-0288
GF-131
Figure 2-6: Location of ACS DIP Switches
AERCO RS485 (MODBUS)
WIRING, BIAS, AND TERMINATION
2.7
The RS485 wiring connections at the AERCO Boilers will depend on the type of AERCO Boilers
and Control Systems being used on the Modbus Network. Benchmark Series and KC1000
Boilers currently utilize C-More Control Systems. Modulex Series Boilers utilize Boiler Control
Modules (BCMs) with E8 Controllers.
2.7.1 RS485 Wiring, Bias, & Termination (BMK & KC1000 Boilers)
RS485 wiring connections are made at the RS485 terminals of each boiler’s I/O Box (Figures 2-
7 or 2-8). However, activating bias and loop termination can be performed using one of two
available methods as described below in
Method A
and on the following page in
Method B
.
Where possible,
Method B
is the preferred method.
Method A:
For Method A, the bias switches in the ACS are left in the deactivated (up) position.
Bias and termination are controlled at the boiler end of the RS485 loop by activating the bias
and termination DIP switches on the PMC board of the last C-More Control Box on the daisy-
chain. Refer to sheet 1 of Figure 2-7 (Benchmark), or Figure 2-8 (KC1000) and proceed as
shown below:
NOTE:
THE BIAS DIP SWITCHES CAN BE ACCESSED FROM
THE WIRING COMPARTMENT WITHOUT REMOVING
THE FRONT PANEL FROM THE UNIT.
WIRING COMPARTMENT
