Issue with fluctuating Analog Output

Pegaia

The module being used is 6es7532-5hd00-0ab0 (AQ 4xUI/ST).

I don't understand what the issue is since the code seems to work all right, and the terminals are wired?

Thanks for the help.

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Hi,

some details of your description are not 100% clear to me:

Hi all,

I'm having trouble with an Analog Output module. I'm using the unscale block for the 1500 and the value given by it is correct (0 - 200 bar, when I enter 100 it gives me 13824 as the output, which is half so that is correct).
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OK, there is no conversion problems.

I understand that these 2follow entries are relactive with full program. Am I right?


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When I measure the output channel, I get values that fluctuate between 4.7 to 4.91V.
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The fluctuation between 4.7 to 4.91V happens when I load the entire program to the PLC. I checked and the channel for that output is only used at the end of the programOB1 and only once.
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Am I right?

and

I understand that it is a test without your user program, just with these two lines of code:


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I tried doing the following test, downloading the code: L 13824 T PQW88 to the PLC, and when I measure the output, I get 4.99V for 10 seconds, then it goes down to 4.84V for other 10 seconds, and after that it goes up to 4.99 and the cycle continues.
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Am I right?


What is strange your description, is that we could be lead to think that it is a hardware (intern / extern) problem (like load capacitance, problems in meter, load too small, etc.), but the behavior changes with the user program (??!)



My suggestions:

1 - Check if the test with the "test program" happens without any other user logic.
2 - Check if your voltimeter /load is ok. If possible remove all relevant load wire, and uses just a voltimeter. Test also wiring the AO to a AI, without any other thing in paralell.

I am sorry this is not clear:

1. When I load the full user program where I use that analog output only one time, the value fluctuates between 4.6 and 4.9V.

2. After checking this I did a test with 2 lines of code (load and transfer only and coded in OB1) and the value fluctuated between 4.84 and 4.99V.

3. What happened before lead me to believe that it may be a grounding issue, which is what I'm going to check the next time I am on site. I'm asking here because I'd like to be there with as much information as possible. Also, with the full user program there are other analog inputs and outputs used, which will also mean that manipulating these may interfere with the analog output where the error occurs. I just tried to detail every test done.

Thanks again for your help!