there are three selector switches on the front of my plc one labeled rn in one position and st in the other. the other is labeled nr,re,and or.the last one is the power switch. does any one know what these other two for. also I am asuming that you require a 25 to 9 pin adaptor for the 6es5 734-1bd20 cable aswell if communicating with your serial port.

 

Hi,

the first 2 are run, stop the next 2. I'm not sure what the letters mean but depending on where and how you operate and this switch with the run, stop switch gives you a couple of restart options. maybe cold restart and warm restart, also a complete memory clear.

hope this sort of helps,
cheers rota

 

Hello, Daniel;

The 3-position switch controls the retentive behavior of different memory zones of the CPU (Counters, Timers, Flags, System Flags) after restart:
NR: non-retentive
RE: Retentive (as set in System data word RS120)
OR: Overall Reset

ASnd you do need a DB9 to DB25 converter to connect the 734-1BD20 cable to a PC COM port.

Download the S5-115U manual from the Siemens website for more information:

http://www4.ad.siemens.de/WW/llisapi.dll?func=cslib.csinfo=en&objID=4000024

Hope this helps,
Daniel Chartier

 

> there are three selector switches on the front of my plc
> one labeled rn in one position and st in the other. <

RN means RUN, ST means STOP, this controls the CPU mode selector.

> the other is labeled nr,re,and or. <

NR means NonRetentive presetting, you do NOT get flags,counters and timers that stay on with power off, RE means REtentive presetting, you DO get flags that stay on with the power off, OR means Overall Reset.

> the last one is the power switch. <

There may also be a switch to reset low backup battery alarm (on the power supply).

> also I am asuming that you require a 25 to 9 pin adaptor for the 6es5 734-1bd20 cable aswell if communicating with your serial port. <

YES!

Meeuwis Bouw
Flamco, NL

 

Hi,

The first switch: rn -Run, st - Stop
Second switch: nr - Non retentive (Flags cleared)
re - Retentive
or - Overall Reset (Program cleared)

Hope this helps!

 

hey danial that link doesn't seem to work could you double check that and email me at [email protected]