On Siemens S5 PLC systems and peripherals, a DB15
connector is used for serial communications. This connector is present
on CPUs, communication processors and operator panels, and in all cases
the used pins and functionality slightly differ. The picture and table
below show the general pin assignment of the Siemens S5 DB15 connector.
Although the pin assignment on the various DB15 connectors on Siemens S5 devices is consistent, the availability of specific signals varies a lot. The TTY
20 mA current loop input and output are available on all devices, but
the current source to power this communication is only found on the CPUs
and a few of the other devices. RS232 signals on the
other hand are not available directly on the CPU programming port, but
most communication processors and operator panels provide them.
Even more cables…
The Siemens operator terminals can be programmed using a normal
serial cable. The following cable can be used to program the OP series
of operator displays.
