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Please feel free to throw some ideas at me how I could use two temp probes with one heater.
Originally I figured I'd use it for redundancy, that if either of the two dropped it would switch on the heater and if either of the two get too high it would switch off the heater.
Now I'm not entirely sure this is even a good idea and even if it was, I'm now not sure this is possible to programme.
Cheers,
Dave
Am I the only person running two temp probes?
I will have one connected to the profilux and one via the expansion card.
There must be a method of using both to control heating/cooling, as a failsafe.
Hi,
on a ProfiLux controller it is possible to use Virtual Sensors.
You can create them by browsing the menu directly on the ProfiLux and goto system->virtual sensors.
There are 2 options available:
- Average of two probes
- Copy of a probe
In your case it would be good to use 'average' of 2 temp probes and set the alarm threshold accordingly.
Then assign the new virtual sensor to the desired switch channel/prog logic.
Brilliant, thank you so much.
If one of the probes fails, or if one is unplugged for cleaning, would it capture the input as zero and average including the zero? As this would trigger the heater to turn on.
If it would do this, it would be a great future feature to “exclude zero input”.
Is it possible to also set an alarm on each of the real probe inputs, so if either gets too low or too high it would trigger an alarm / email?
The probe alarm or zero-input would not trigger-on the switchchannel.
You can pre-configure the virtual probe setup quite easily in GHL Control Center's and its multi-window functionality and test yourself.
See the screenshots below:
Attachment 11996
Attachment 11997
Hi Matthias,
In your first screenshot, real sensor 1 is zero, real sensor 2 is 24.5 and the virtual sensor is 12.3.
So the average is considering zero input.
I guess zero could only be achieved with faulty sensor or unplugged?
So in this instance, the virtual sensor would trigger the heater on and it’d be stuck on forever or until the heater broke.
I did this test myself, but figured I must have been doing something wrong, as I got the same result.
I think the average functionality is only good if both probes are fully functional, if you ever have an issue, it would boil your tank.
Do you agree?
Is there a way to handle this?
Ideally, if either of the probes registers zero then it should default to the working value.
That’s what I meant by “exclude zero input”.
Would it be possible to put an override using programming logic to detect zero on either probe and force the heater to stay off until the situation was resolved?
Am I misunderstanding something?
Many thanks,
Dave
The first screenshot shows that the switchchannel 'temperature 2 (Heater) IS OFF, while there's no/zero temperature input.
And of course, the alarm range can deactivate controlling if you set it to your desired values.
So it does.
My mistake, sorry. I missed the key bit of information “switch channel”.
Thank you very much for your patience.