Hello All

I'm trying to read a 0-5v sensor value using a 6ES7-231-4HD32-0XB0 module ( 12bit+1 signed bit, 4 Analog inputs).

and getting some doubts if its al going as it should be because if i disconnect the sensor from the connector (leaving the plc wired) my input word value goes to 12150 leaving me after scaling it not going to 0 what I'm wishing for.

its the first time for me using this module so help is welcome.

what ive done for so far.

- because im using a 0-5v sensor i set the input channel voltage range to +/-5v as its not able to go to 0-5v.

- Using a 3 wire sensor ive conected the sensor like  this :

and programmed it like this :

when i connect the sensor I'm getting the value of 27818, a bit of a overflow but not a problem for now.

as far as i understood i have to use these values on max en min at the Norm_X althow it is a 12+signed bit.

Ive also noticed that when the sensor is disconnected and i'm measuring from analog input connections 0- to 0+ im have 1.0 volts between them, this difference goes away when im disconnecting the mass.

somebody can tell me what I'm missing here ?

Hello,

I'm not sure but I think you need do like this: First I think if you choose +- 5V range so it means then get -5V to your AI card you in program will see 0 then you get +5V you will get 27648, so 0V is at middle -5V and +5V, so half of max value will be 13824, so in NORM_X you need write: MIN 13824=0V; MAX 27648=+5V; if you get less then 13824 you will tract it as wire brake.

Also add your sensor type maybe something wrong in wiring

Mr.V

First I think if you choose +- 5V range so it means then get -5V to your AI card you in program will see 0 <snip>

There's nothing to discover. Everything is described in the manual. 

thanks for your awnser.

it is indeed giving quite a good value..

after this change.

i get this value with no sensor connected and the ai0-  connected to the mass.  so i would sugget it would be the same as 0volts analog output

but as i read the manual  and see this:

i would say that when the voltage range is selected on +/-5 volt.

that no sensor (0volt) should give a value of 0 .

Then the value goes to 0.

This is the moment you tell me my way of testing 0volts due disconnecting the sensor was nog appropriatie as it isnst the same as zero volts from the sensor  because its an undefined signal?