Programmable Logic: Need help to shutoff heater if flow sensor reads 0 flow

AquaLifeStudio · Feb 10, 2019

If anybody can figure something out that would allow this flow sensor to cut power to the heater socket WHILE also allowing the heater to be controlled by the temperature probe at the same time... that would be awesome.

I would think that it would be possible to write an available function for the flow sensor rather than having to operate through a "work-around" though I wouldn't mind that either as long as it works how I want it to.

Lasse · Feb 10, 2019

Dittos solution with using general alarm should work.

1) figure out which level sensor your flow meter is conected to . If you have (P3.x) two inputs - figure out which you connect the flow meter to. P4 have 4 inputs.

We use flow sensor 1 and have figure out that it react on sensor 1

Set alarm point - i have chose 1000l/h

Go to the level section

Set the reaction time to around 10 sec in the settings and states level sensor section for the selected sensor - I chose 10 sec

Now we go to to the Programing logic part. Have with you which temperature controler you want to use

I use G10 and temperature 1 heater

Hit OK and now you chose the function AND - configure the second rule - chose general alarm and check the box Inverted

Now you have a PL with number G10 - (you can use the one you want)

Now - go to the section Switch channels and outlet - chose your actual output - I have take channel 17. Put in your programin logic - for me G10

Now - channel will be on if the temeperature 1 says that it should and if you do not have a general alarm. If it T1 says on but you have a general alarm - it is of. If T1 says no and no general alarm - off and if T1 is of and you have a general alarm - off. Tha backside with this is that the heater will not work as soon you get any alarm at all.

The trich here is that you chose inverted function in the box for PL and general alarm

This should work.

Sincerely Lasse

Ditto · Feb 10, 2019

@Lasse - thank you was just going to post, the general alarm works without any issue

Just note any general alarm will turn off the heater.

I did get Lasse to work also but the issue was would not always go off when testing, or a few times never went off the above method worked every time.