Stopping dripping KALK water when pH >8.39

[Rst]

I am using a peristaltic dosing pump to drip in RO water at a very low drip rate into an Avast Marine KALK reactor. I am not sure how to program the dosing pump so that it normally runs constantly 24hours per day and only stops dosing if the pH happens to rise above 8.39 pH. If the pH does go above 8.39, I also want to turn off the dosing pump for 1 hour before it resumes dosing again.

Will this code work:

Fallback OFF
Set ON
If pH_Kalk > 8.39 Then OFF
Min Time 060:00 Then ON

Thanks

 

[Justdrew]

I am using a peristaltic dosing pump to drip in RO water at a very low drip rate into an Avast Marine KALK reactor. I am not sure how to program the dosing pump so that it normally runs constantly 24hours per day and only stops dosing if the pH happens to rise above 8.39 pH. If the pH does go above 8.39, I also want to turn off the dosing pump for 1 hour before it resumes dosing again.

Will this code work:

Fallback OFF
Set ON
If pH_Kalk > 8.39 Then OFF
Min Time 060:00 Then ON

Thanks

There are other more savvy APEX programmers out there to answer the programming question. My concern is missing an hours worth of dosing would cause instability with your ALK levels. I use the defer statement to delay my skimer turing on. Don't know if that is the situation for that.

 

[Rst]

There are other more savvy APEX programmers out there to answer the programming question. My concern is missing an hours worth of dosing would cause instability with your ALK levels. I use the defer statement to delay my skimer turing on. Don't know if that is the situation for that.

Thanks. I tried Defer first, but maybe I didn’t code it correctly, this kept turning On & Off at the pH around 8.39.

Currently I found that the Min Time 060:00 then ON didn’t work. I have am now trying this instead:
Min Time 060:00 then OFF

Hope this works

 

[ZombieEngineer]

You want Min Time then OFF

An alternate method is hysteresis like this

Fallback OFF
If pH < 8.3 Then ON
If pH > 8.4 Then OFF

 

[Rst]

You want Min Time then OFF

An alternate method is hysteresis like this

Fallback OFF
If pH < 8.3 Then ON
If pH > 8.4 Then OFF

Now that I know what code works, I now will resume trial & error to find what spread of on/off cycles will let the display tank’s pH keep below 8.39 and not cycle too frequently. I will experiment with both these 2 coding methods to see which seems more appropriate.
Thanks for your help & suggestion.