Subtracting Totaliser

[russedwards]

Hi 

 

I am looking for some advice for a function I am looking to add to a V570.

 

We are monitoring the amount if fluid lost in a small reservoir and I need to keep track of the water that is lost daily.  At the moment I can quite easily take a reading at the start of the day, a reading at the end of the day, subtract the 2 using a Maths FB and get the result I am looking for.

 

Now for the part that is confusing me!

 

The reservoir can be topped up, so this would not make my reading accurate.  For example, at the start of the day the level could read 1000 liters, at 12 pm the level could read 800 liters, but at 1 pm the reservoir could be topped back up to 1000 litres.  At 5pm when I take my last reading reservoir level would could read 900 liters.  Using my current calculating method, the result would show that the reservoir had only lost 100 liters when in fact I had actually lost 300 liters in total through the day.

 

Is there anyway I can get the controller to "ignore" the topping up of the reservoir or allow for any increase in level?

 

Any ideas would be gratefully received!

 

Thanks

[AlexUT]

Hi,

Ideal is to register filling and consumption. Level detectors will help against overflow.

As I see, you already have consumption meter. When you add filling meter - you will have 2 numbers - income and outcome.

Difference will be read at the end of day.

I hope this helps.

[russedwards]

Hi Alex

 

Thanks for the suggestion.  I have managed to separate the filling and consumption figures as you mentioned.