Problem analog value S7 PLC

Hello,

I am having difficulties setting up an analog measuring system with an S7 319F PLC.
The analog card is a 331-1KFO2-0AB0 13bit.
I have two of these cards in the configuration, both measure exactly the same; the feedback of a current supply, 2 analog values 0-5V.
At first the cards worked fine, but recently I see that the first card is working properly.
I measure the voltage on the connections (ex between 1 and 5) and that is a positive value, but when I check the value of the PEW it is negative?
The settings of both cards are exactly the same; +-5V

Does anyone have any experience with this?

Best regards,
Jeroen

a word can not be negative so your error is in the VAR part.

yes, try with INT instead of WORD

At this point, the problem is gone: after recompiling the hardware and safety and downloading it again, the problem is gone;
I find this very strange, as I have not changed anything in the hardwareparameters.

But still thank you for the reply.

i noticed that in first post you mentioned 0-5V then -+5V.

Jeroen Benoot said:

Hello,

I am having difficulties setting up an analog measuring system with an S7 319F PLC.
The analog card is a 331-1KFO2-0AB0 13bit.
I have two of these cards in the configuration, both measure exactly the same; the feedback of a current supply, 2 analog values 0-5V.

(...)

The settings of both cards are exactly the same; +-5V

Click to expand...

maybe you forgot to recompile and download the new system conf. settings

What I meant to say was that the settings of the input card are +-5V, (there is no 0-5V) and the value from the current supply is 0-5V, this should work like this.

I have experienced some similar, sometimes crazy values, on the same type of AI card.

In this case there was no ground/minus on terminal 10 & 11, do you have that?

Also the "negative" side of the channel must in many cases be grounded, but be careful with you potentials.

I can't remember how to do with +/- 5V or 0-5V, but read the manual. My guess will be yes.