AERCO Modbus Communications Manual for ECS - Manual (Page 6)

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Table 1. MODBUS Communication Signal Connections
2408 TEMPERATURE
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+
1A HA
1B HB
1C HC
2A
2B
1D
HE
HF
HD
3B
3D
3C
2D
3A
2C
JD
JF
JE
JB
JC
JA
LA
LB
LC
AA
AB
AC
VI
V+
V-
In1
In2
C
2408 CONTROLLER
L
N
Figure 1. Temperature Controller (Eurotherm 2408) Terminal Connection Diagram
4. MODBUS COMMUNICATION INFORMATION
The Eurotherm 2400 Controller supports the MODBUS RTU mode of transmission. The default settings
are as follows:
• 9600 baud rate
• One start bit
• Eight data bits
• One stop bit
• No parity