Moeller ps4-201-mm1, Hardware And Engineering

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Elements
11
04/
99 AW
B
27-
1184 G
B
Programming device interface (PRG)
The RS 232 interface is galvanically isolated from the
CPU. It has the following functions:
Programming the PLC via the PC
Data exchange with partner devices that have a
serial port (printers, terminals, etc.). This type of
communication is used for process data
acquisition, visualization etc. but should not be
used to exchange data for process control (see
also “Function block SCO” in the manual
“Language Elements of the PS4-150/-200/-300
and PS416” in AWB2700-1306GB, chapter 6).
Memory modules
The PS4-200 has an internal, battery-backed,
32 kByte RAM. The memory is subdivided into a data
memory and a user program memory.
Up to 24 Kbyte are available for the user program.
This allocation is dynamic, i.e. if the data memory
requires more than 8 Kbyte, the size of the user
program memory is reduced accordingly.
The memory capacity of the internal RAM can be
expanded with plug-in memory modules. The
available modules are as follows:
The 32 Kbyte RAM module expands the user
program memory. Up to 56 Kbyte can then be
allocated to this memory.