Programming Apex help

[AnacapaReefs]

I have two temp probes Tmp_L and Tmp_R. Id like to set them up so that if one fails, it sends me an alert, and falls back to the other. This would have to go both ways. I use them to control my heaters.

 

[SuncrestReef]

The big question is: How would you know if one failed from a programming perspective?

 

[AnacapaReefs]

The big question is: How would you know if one failed from a programming perspective?

If it is reading unreasonable temps

 

[AnacapaReefs]

If it would work, I would get a third probe and if one is reading differently then the other two, it would ignore it.

 

[SuncrestReef]

Unfortunately the Apex programming language does not permit any way to directly compare two probe readings. The best you can do is to compare a probe value against a static number; for example:

If Tmp_L < 78.0 Then ON

In order to compare multiple probe readings, you'd need to utilize a virtual output:

TmpL_Compare
------------------------
Set OFF
If Tmp_L < 78.0 Then ON

TmpR_Compare
-----------------------
If Output TmpL_Compare = ON Then ON
If Tmp_R > 78.0 Then OFF

So if output TmpR_Compare = OFF, then that means that Tmp_L is reading lower than Tmp_R.

As you can see, this isn't really scalable because you might need to compare things over a range of temperatures.

 

[AnacapaReefs]

Unfortunately the Apex programming language does not permit any way to directly compare two probe readings. The best you can do is to compare a probe value against a static number; for example:

If Tmp_L < 78.0 Then ON

In order to compare multiple probe readings, you'd need to utilize a virtual output:

TmpL_Compare
------------------------
Set OFF
If Tmp_L < 78.0 Then ON

TmpR_Compare
-----------------------
If Output TmpL_Compare = ON Then ON
If Tmp_R > 78.0 Then OFF

So if output TmpR_Compare = OFF, then that means that Tmp_L is reading lower than Tmp_R.

As you can see, this isn't really scalable because you might need to compare things over a range of temperatures.

Thanks!