Siemens Analog input wiring problem

[Amr Hassan]

Dear All

i am using a siemens 6ES7331-1KF01-0AB0 card as ana anlog input


my sensor uses seperate power supply so i have 2 wires with +,- 24 v and two wires connected to th ai card (pin 2,5) for example.

i noticed that if we disconnect the -24 volt wire of one sensor , all chanels fail


what should i do ?

 

[PeterMalt]

Hi there,


What type of signals do you havenand how did you configure the
6ES7331-1KF01-0AB0 ?

When connecting voltage and current sensors, ensure that the maximum permissible common mode voltage U​

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CM of 2 V is not exceeded between the inputs. To prevent incorrect measurements being made, you should therefore connect the different M– connections to each other.
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When measuring resistances and resistance thermometers, the M​

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– connections do not have to be interconnected.
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Maybe you can get information here http://www.ad.siemens.com.cn/download_test/manual/en/as/manual/PI_RHB_e.pdf
​

de M-analog is not isolated from other channels, this gives sometimes strange behavior.

 

[neman]

check if ur power and sensor gnd or -ve r common or not

 

[apuskas1986]

Possible problem to your wiring is if you have a current input (4-20mA) and if your input is programed as current input and wire break fail is active. In that case when you remove the supply AI card will register fault as 0mA is at input.