Watlow CPC400 - Manual (Page 57)

CPC400 Series User’s Guide Chapter 2: Installation
Doc. 0600-2900-2000 Watlow Anafaze 43
EIA/TIA-485 Interface
To communicate with more than one CPC400 series con-
troller on a controller network, or to use communication ca-
ble lengths greater than 50 feet (15 m) from PC to
controller, you must use EIA/TIA-485 communications.
When using EIA/TIA-485 communications, you must at-
tach a 232-to-485 converter to the computer. Figure 2.31
and Figure 2.32 show the recommended system wiring.
Figure 2.31 Four-Wire EIA/TIA-485 Wiring
Figure 2.32 Two-Wire EIA/TIA-485 Wiring
Personal
Computer
232-to 485
Converter
First
CPC400
Last
CPC400
TXA/TDA/TX-
TXB/TDB/TX+
RXA/RDA/RX-
RXB/RDB/RX+
RXA 25
RXB 23
TXA 26
TXB 24
RXA 25
RXB 23
TXA 26
TXB 24
Do not
connect
shield to
CPC400.
JU1
A
B
JU1
A
B
Personal
Computer
232-to 485
Converter
First
CPC400
Last
CPC400
TXA/TDA/TX-
TXB/TDB/TX+
RXA/RDA/RX-
RXB/RDB/RX+
RXA 25
RXB 23
TXA 26
TXB 24
RXA 25
RXB 23
TXA 26
TXB 24
Do not
connect
shield to
CPC400.
JU1
A
B
JU1
A
B