AERCO Electronic Controls System (ECS) - Manual (Page 20)

Electronic Control System (ECS) and Type CXT-E Valve
2. INSTALLATION
Page 20 of 82
AERCO International, Inc. • 100 Oritani Dr. • Blauvelt, New York 10913 • Phone: 800-526-0288 VD2: 02/28/14
OMM-0003_0D AC-105
CAUTION!
DO NOT route Modbus communication wiring in the same
conduit as power wiring. Attempting to do so may result in
excessive noise on the signal lines. Also, ensure that the RS232
or RS485 signal cable connections do not exceed the following
lengths:
RS232 Cable: 50 feet maximum
RS485 Cable: 4,000 feet maximum
8) To permit Modbus control of the ECS, refer to Table 2-1 and connect the appropriate wire
leads to the Temperature Controller terminals listed. Refer to the Temperature Controller
(Eurotherm 2408) pinouts shown in Figure 2-6 to locate the required terminals. Also, refer
to Appendix A for a listing of active Modbus data addresses for the 2408 Controller. In
addition, the Eurotherm documents referenced in this Appendix provide additional
communication information related to Modbus.
NOTE:
The complete wiring diagram for the Electronic Control System is
provided in Appendix B of this Instruction Manual. In addition, the
wiring connections for Terminal Blocks TB-1 and TB-2 are provided
for reference purposes.
NOTE:
AERCO recommends that shielded, twisted-pair cable be used for
communication wiring. Examples of suitable wiring are: Belden 9841,
8761, 3105A, or equivalent.
Table 2-1. Modbus Communication Signal Connections
2408 TEMP. CONTROLLER
COMPUTER CONTROL CABLE
RS232/9-PIN RS232/25-PIN RS485
SIGNAL NAME PIN NO. SIGNAL NAME PIN NO. PIN NO. PIN NO.
GROUND HD GROUND 5 7 GROUND
RECEIVE HE TRANSMIT 3 2 A (-)
TRANSMIT HF RECEIVE 2 3 B (+)