Hallo ,
Which transducer should I use to connect an ORP probe to an analog port Logo 8?
Thank you in advance​

Hello Jeden;

I beleive what ixo65 is looking for is a range value for the output of your ORP probe.

If I remember an old project we worked on, the ORP probe we used produced an output voltage of ± 100mV.

To convert such a signal to 0-10 V for the analo input of a Logo!, you could use (as an example) a signal conditionner such as this one:

https://www.automationdirect.com/adc/shopping/catalog/process_control_-a-_measurement/signal_conditioners/dc_voltage,_current_or_potentiometer_input/fc-b34

So we need to know the output range of the ORP probe you will use, in order to provide better help.There are many manufacturers of signal conditionner with many different offerings, such as Phoenix Contacts, Omega, and of course Automation Direct, as shown above. Do your research based on your requirements.

Just remember that the output of an ORP probe is highly non-linear, so you will have to us caution when you interpret the voltage value coming from the signal conditionner.

Hope ths helps,

Daniel Chartier

We need to know what output gives your sensors then will be much more easy to know what to do.

But i find in aliexpress module converting from variuos voltage to 0-10 enter in google like this:

Positive and negative voltage small signal conversion module weighing conditioning 0-20mv/5V/10V/20MA bipolar high bandwidth

thanks everyone for the effort.
I can only measure microampere. 
So I will have to amplify this signal first