
NOTICE!
Risk of damaging the terminal base!
Terminal base can be damaged by connecting the power supply terminal block
(L+/M) to COM1.
Make sure that the COM1 terminal block is always connected to the terminal
base even if you do not use COM1 to prevent this.
NOTICE!
Risk of damaging the terminal base!
Excessive current might damage the clamp and terminal base.
Make sure that the current flowing through the removable clamps never
exceeds 8 A (with 1.5 mm
2
conductor).
1.1.1.2.3 Serial Interfaces COM1/COM2
The serial interface COM1 is connected to a removable 9-pin terminal block. It is configurable
for RS-232 and RS-485 and can be used (depending on the processor module) for:
● Online access (RS-232 programming interface for Automation Builder)
● A free protocol
● Modbus RTU, client and server
● CS31 system bus (RS-485), as master only
Chapter 2.6.4.8.2 “Wiring” on page 1283
Pin
Signal
Interface
Description
Terminal
block
removed
Terminal
block
inserted
1
Terminator P
RS-485
Terminator P
2
RxD/TxD-P
RS-485
Receive/Transmit,
positive
3
RxD/TxD-N
RS-485
Receive/Transmit,
negative
4
Terminator N
RS-485
Terminator N
5
RTS
RS-232
Request to send
(output)
6
TxD
RS-232
Transmit data
(output)
7
SGND
Signal Ground
Signal Ground
8
RxD
RS-232
Receive data
(input)
9
CTS
RS-232
Clear to send
(input)
NOTICE!
Unused connector!
Make sure that the terminal block is always connected to the terminal base,
even if you do not use the interface.
Serial Interface
COM1
Pin assignment
Device Specifications
Terminal Bases (AC500 Standard) > TB51x-TB54x
2019/04/17
3ADR010121, 13, en_US
8