The Instruction for Use of PC/MPI Adapter
PC / MPI adapter is also known as PC adapter. It’s physical
interface is the conversion from RS232 interfaces to the
RS485,including the conversion from RS232 to MPI protocol
(MultiPoint Interface).And it is used for the connecting between
the PC COM (RS232) and MPI (RS485) of Siemens S7-300PLC.This
product is non-isolate, choose PC / MPI + if you need an
electro-optical isolation.
Main technical parameters：
RS232 Port baud rate：19.2Kbps
MPI Port baud rate：187.5Kbps
With the data received and sent indicator light
Temperature：0～75℃
Total length of cable：5m
STEP7 Software settings：
1、 Go into STEP7 the main software programming interface（SIMATIC
Manager）click Set PG/PC Interfacewhich is under the Options” menu,
and the get to the PG/PC setting interface
2、 Double-click on PC Adapter（Auto）”orPC Adapter（MPI）”to go into
the interface setting of parameters of RS232 and the MPI. The
adapter does not support "PC Adapter (PROFIBUS)" option.
3、 Click on the "Local Connection" option to set the interface
parameters of RS232, to choose the right computers COM mouth
(RS232), change the RS232 communication baud rate to 19200 bps.
4、 Click the "MPI" option (if it's on "PC Adapter (MPI)" method) to
set MPI interface parameters for the adapter, as the MPI interface
of the adapter gets the baud rate fixed at 187.5 Kbps, so here can
only be set to 187.5 Kbps.
If it is "PC Adapter (Auto)" method the choice should be "Address:
0" and "Timeout: 30s".
After the settings above the adapter can be set up on-line
communication with the PLC, now you should pay attention to thatyou
shouldn’t change the factory default of the MPI port baud rate
187.5Kpbs on the CPU which is under the Network Settings”.
Since the baud rate of the MPI port of the adapter is fixed at
187.5Kbps, if it is set at other figures, the adapter will not work
with PLC! Make sure that the baud rate of the MPI port on your
S7-300PLC’s CPU is fixed at 187.5Kpbs.Otherwise,you have to use the
Siemens's programming communication facility to set that baud rate
to 187.5Kpbs,in order to make the adapter work correctly.
