Problem receive AI signal with ET200s

Dear All,

I try to receive signal from ET-200S 4wire/2AI module 13bits  (6ES7134-4GB11-0AB0). i connect my AI source to terminal point 5 and 6 and I use my multimeter to check the mA is around 17mA but my PLC show that around 16#10CA. By right it should show more  than 16#4EE5. i try to switch with terminal point 1 and 2 but i still getting the same result.

Is that anything I can do?

for more information, this is distributed IO system. we using profibus and the distance is around 100m. My PLC show that all module is ok and available. 

I try to replace new IO module but getting the same result. So i think is not the hardware issue. Is that any software setting i can do? 

Hello,

On pIn7 and pin8 should be wired the same power supply of current source, shouldn't it?

Best regards,

Hristo Mihalev

UMENCHO

Hello,

On pIn7 and pin8 should be wired the same power supply of current source, shouldn't it?

Best regards,

Hristo Mihalev

 Hi, 

For the pin7 and 8 i try to use multimeter to measure the dc voltage is 24vdc. I think is not necessary to connect same source of the currect source. In my other project pin 7 and 8 is not connected. Furthermore, my current power source is 220vac (this is 4 wire instrument). 

Here attached with the instrument data sheet. This one is the level indicator and i connect the current source from the "DC 4~20mA".

Is that any possible this issue related to the input impedance? 

hi chlooi,

have you checked the mesurement mode? Maybe it is on +/-20mA.

Or like UMENCHO said, there is a potential difference in your system. 

regards,

mopS04

hi chlooi,

have you checked the mesurement mode? Maybe it is on +/-20mA.

Or like UMENCHO said, there is a potential difference in your system. 

regards,

 Hi, 

Will try it tomorrow about the +-20mA. 

Btw, how to solve the potential difference? Pin 7 and 8 connect 24vdc? 

 I Try to connect AI- with pin 8. One channel problem solve but for the other channel problem still same. Will try to find other solution.

This 2 channel connect same type of instrument. But this method only work with one channel. Other channel use this method will cause the instrument error. 

Hello,

You didn't wired correctly. The card is 4wire 4-20mA or +-20mA. Take in consideration the wiring. Just follow the corresponding manual. So, pin5 and pin6 are the current pin7 and pin8 are the current source power supply. The other channel they are pin1 and pin2 are the current, pin3 and pin4 are the current source power supply. 

Make the differences between 2wire and 4 wire current wiring. Here in forum had a discussion about that.

Best regards,

Hristo Mihalev