Temp Probe affected by MP40?

[JeF4y]

I have an Apex controller, and my temp probe sits in my overflow. I recently moved my MP40w to the back side of the tank and it now sits about 4-5" away from the temp probe. As soon as I did that, my temp probe began acting somewhat funky. It's not REAL crazy or anything, just a bit odd..



Sunday was when I moved it... Nothing else has changed. Does anyone know if magnetics or the electronics here would effect the temp probe?

(and that low dip was a water change if you're curious)

Thanks in advance.

[apjohnson]

I had an IceCap 400 W electronic ballasts cause interference with my temp probe from about 12" to 18" away. I can't speak for sure to say that's what your issue is, but I wouldn't rule out the Vortech.

--AJ

[aquamanic]

I know small magnets don't have any effect on the temp probe but those MP40 magnets are monsters. Wouldn't surprise me if it did. Easy enough to test though.

[JeF4y]

Yep. Will have to move the probe which kinda stinks. Having it in the overflow was nice because it was hidden and didn't grow coraline all over it.

[swannking]

Originally Posted by JeF4y

Yep. Will have to move the probe which kinda stinks. Having it in the overflow was nice because it was hidden and didn't grow coraline all over it.

I thought about putting the temp in the overflow or the sump before but decided not to for one reason. My AC3 control the MH light and if the tank temp is too high, it will shut them down. Now what if I am not home and my main return pump fails. The tank water will no longer go to the overflow where the temp is being measured. The tank can be cooked with the MH and the temp in the overflow will still be nice and cool.

[JeF4y]

Success!

It actually didn't have to do with the placement of the MP40 but the cord going to it. I shuffled the two away from each other and voila! back on stable ground.

Originally Posted by swannking

I thought about putting the temp in the overflow or the sump before but decided not to for one reason. My AC3 control the MH light and if the tank temp is too high, it will shut them down. Now what if I am not home and my main return pump fails. The tank water will no longer go to the overflow where the temp is being measured. The tank can be cooked with the MH and the temp in the overflow will still be nice and cool.

T5's here. No MH heat issues. Yes, if flow stops to the overflow, the temp will vary slightly from the display but not by that much. And even if it did force my heaters on, I have them dialed to stop at 80. So while not impossible, it would take multiple failures to cook my tank based on where the temp probe is. But you do make a good point (which is the main reason I have the probe in the display as well as a heater in the display and one in the sump).

[aquamanic]

It actually didn't have to do with the placement of the MP40 but the cord going to it. I shuffled the two away from each other and voila! back on stable ground.

One other thing you could try if you don't want to move your probe or MP40 is to add the Defer statement after your 'If Temp' statement. That will smooth brief interference induced swings of the probe value. It essentially will force the probe to have that value for 1 - 2 minutes (or whatever you decide) before it reports it. If it changes in that time, then the clock starts over.