Nitrate filter ORP negative numbers reading.

[Rick Strauss]

I have a deltec nitrate filter and a pin point ORP controller. How do I get the pinpoint to read and control negative ORP numbers? Any help would be greatly appreciated.

 

[lapin]

While I think it can read negative ORP according to the instructions, it looks like it cant control negative ORP
Measurement Range –1,999 to +1,999 mV
ORP Setpoint Range 0 to 1,000 mV

 

[Rick Strauss]

Thank you I believe you’re correct. How do you go about controlling negative ORP?

 

[ca1ore]

Although both will display negative ORP, neither the pinpoint nor the Milwaukee can control in the negative range. Not sure how you’d automatically adjust negative ORP even if the controllers were capable. Maybe that’s why they don’t do it.

 

[Rick Strauss]

Maybe if I cut the probe wires and reversed them that way the controller would think it was positive?? Do you think that would work? I believe it will control whether it’s going up or down but just on the positive side.

 

[ca1ore]

Even if that did ‘fool’ the controller, what would you actually be controlling to keep the ORP within your target range. I run a sulfur reactor and the only thing that affects ORP is adjusting effluent flow rate. How would you automate that? All ears if you have a way to do it.