____________________________________________________________________________________________________________
V2
AC500 Hardware
1-33 System
data
AC500 / Issued: 05.2007
Replacement of modules on the I/O bus
The I/O-Bus is not designed for plugging and unplugging modules while in operation. If a module is
plugged or replaced while the bus is in operation, the following consequences are possible
•
reset of the station or of the CPU
•
system
lockup
Caution:
Removal of energized modules is not permitted. All power sources (supply and process
voltages) must be switched off while working on any AC500 system.
Serial interfaces of the CPU Terminal Bases
Interface standards
The serial interfaces COM1 and COM2 are designed according to the standards EIA RS-232 and EIA
RS-485. Both interfaces can be operated either in RS-232 or in RS-485 mode.
Technical data
Standard of the serial interfaces
EIA RS-232 or EIA RS-485
Interface connectors
COM1: 9-pole removable terminal block
COM2: 9-pole Sub-D connector (female)
Electrical isolation
yes, against the CPU, 500 V DC
Serial interface parameters
configurable by the software
Operating modes
programming or data exchange
Supported protocols
Modbus or serial data exchange using special
software function blocks
COM1 can be configured and terminated for either RS-232 or RS-485 (depending on used terminals).
Please terminate according to the pin-out information for the COM1 port below and follow the
appropriate rules and practices for RS-232 and RS-485 communication.
Serial interface COM1 of the CPU Terminal Bases
L+
M
L+
M
FE
1
2
3
4
5
6
7
8
9
+24 V DC
0 V
+24 V DC
0 V
Functional Earth
Term. P
Term. N
RTS
TxD
SGND
RxD
CTS
COM1 9-pole, terminals
Terminator P
Receive/Transmit, positive
Receive/Transmit, negative
Terminator N
Request To Send (output)
Transmit Data (output)
Signal Ground
Receive Data (input)
Clear To Send (input)
Supply voltage 24 V DC, 5-pole, terminals
UP
UP
ZP
ZP
Terminal block
removed
FE
Terminal block inserted
ZP/UP
COM1
RS-485
RS-485
RS-485
RS-485
RS-232
RS-232
RS-232
RS-232
RxD/TxD-P
RxD/TxD-N
Figure: Serial interface COM1