Siemens ET200B 4AO module

nedunche

Member
Join Date
Oct 2007
Location
SINGAPORE
Posts
4
I have a Siemens analog output module 0 to 10V(6ES7135-0HF01-0XB0) which is connected to a analog meter 0 to 10v. this meter sometimes shows erratic readout due to noise. How can I eliminate the erratic behaviour of this?
 
I'm not an expert on Siemens, but two things come to mind:

Shielded and/or Twisted pair cable between AO and Meter

Have a look at your program, is there any way the parameters that give the AO can cause the change?
If you are making some math on that value this might be the problem.

Michal Rudbeck-Rønne
M2R
 
Thanks Michal for your reply. I am using the Twisted shield pair for the analog meter and the shield cables and ground cables are properly grounded. This is a stand alone system and When this system is run alone the meter works fine and correctly. It's only when some other systems are run then it causes the meter to behave erratically.
 
Hmmm,

Could it be the meter that is not EMC safe?

It's been quite some time since I had to do with EMC correct grounding, but I remember something about closing the ground loop and not closing it and in the latter case in what end of the cable should it be grounded. But I would say normally ground the cable in the end at the PLC, but then again that could make the cable work as an antenne for noise that is then "broadcast" in the ungrounded end i.e. at the mater. You'll have to ask the expert about when to use what method, as I never really got that part under my skin.

Michal
 
Thanks Michal for your reply


Yes, I checked with some people and they said shielding of cables are done only on the PLC end. As I had mentioned before, this erratic behaviour occurs only due to its surrounding(inductive coupling.)I've confirmed that all the shield and ground are connected accordingly.

I was wondering if there is somekind of barrier that can be installed before the meter to solve this problem.
 
Is there any vsd's in the vacinity? If so make so that they are connected properly with shielded cables. We had alot of problems with vsd and the switching frequencies. On some drives you can lower the switching frequencies. Hope this helps
 
Hello,

I have exactly the same problem that you describe with a Siemens ET200b analog output module, also with a 1-10 volt meter.

Was your problem resolved, and if so, what was the cause?

Albert
 
What are you doing with the signal? If it does not have to do anything fast like a PID loop then look into smoothing. In the hardware config select the analog module and look in properties. Then look at smoothing. You should have 3 different levels of smoothing that should help with noise.

edit:
sorry I was thinking inputs not outputs. I am unsure if outputs have smoothing but it would be something to check on.
 
Last edited:

Similar Topics

I was curious if anyone has ever in their experience come across and issue similar to mine with the same hardware. Basically this remote i/o...
Replies
3
Views
2,936
OK. You guys helped me out a bunch with my first Siemens question. I found a bunch of issues with integrity checking the PLC programs I was...
Replies
3
Views
104
Hi, I have a 1214 on ip 192.168.0.100. This is connected to other modules through a switch on same network. I need to connect this to a company...
Replies
1
Views
95
Hello. I appreciate the insights here and the willingness to share. I've got a lot of Rockwell experience, but my Siemens experience is...
Replies
6
Views
130
Kindly, has anyone tried to control Lenze servomotors with Siemens S120 drives ? Any special hints ? Have some concerns for the resolver and servo...
Replies
5
Views
178
Back
Top Bottom