Detect current direction in water

[hackhard]

a bowl is filled with tap water .electric current is made to flow due to electrodes attached to rim of bowl(opposite sides of bowl)
i have 2 sense pins inserted into the water between the electrodes .
how can i convert this analog signal(vd across sense pins) to a digital signal to detect direction of current through water and use the signal in a logic circuit?
the 2 sense pins are fixed in water whereas polarity of supply electrodes is varying with time
electrode vd is max 5v min -5V. ammeter reads 700 microamps current flowing through water

 

[cnh1995]

a bowl is filled with tap water .electric current is made to flow due to electrodes attached to rim of bowl(opposite sides of bowl)
i have 2 sense pins inserted into the water between the electrodes .
how can i convert this analog signal(vd across sense pins) to a digital signal to detect direction of current through water ?
the 2 sense pins are fixed in water whereas polarity of supply electrodes is varying with time
electrode vd is max 5v. ammeter reads 700 microamps current flowing through water

Are you doing this for some project? If budget is not a concern, you can try a hall effect current sensor.

 

[hackhard]

Are you doing this for some project? If budget is not a concern, you can try a hall effect current sensor.

yes all i need to know is if vd across sense pins is + or -ve
+ve or 0 vd = high output
-ve vd = low otput

 

[cnh1995]

yes all i need to know is if vd across sense pins is + or -ve
+ve or 0 vd = high output
-ve vd = low otput

Ok so you are interested in only the direction of the current? Not magnitude? Also, are you using a microcontroller?

 

[hackhard]

Also, are you using a microcontroller?

no I am not
is there any alternative to adc?

 

[cnh1995]

is there any alternative to adc?

I don't think so. Do the sensor pins detect current and give voltage as the output? It would be better if you posted a schematic.

 

[hackhard]

will opamp voltage comparator do the job

 

[cnh1995]

will opamp voltage comparator do the job

Yes. But it won't be able to read the magnitude of the current. It will sense only the direction.