NTC Temp Probes with RCA connections

[GoldenBear]

Hey all,

Wondering if anyone has had any performance issues by using RCA connections between an NTC probe and a temp controller?

As I understand it, NTC probes use resistance (10k with the one I have apparently) and I'm hoping an RCA won't mess with the readings by altering the resistance of the probe wire.

Any feedback would be much appreciated!

James.

 

[billygoat]

If you make a good connection you won't have any problems.

 

[dicko]

I have used them on Fridgemate controllers for ten years without an issue.

You will need a good hobby type soldering iron and reasonable soldering skills, or get someone to fit them for you.

On a side note, it was the best thing I ever did because you can disconnect the controller without removing the probe from the unit it controls.

 

[GoldenBear]

Yeah that's the idea - I want to leave the thermowell in my fermenting fridge, and be able to use the controller for mashing.

Cheers.

 

[QldKev]

I prefer the XLR plugs, they have more contact area and hence a lower resistance. Also give a nice chunky fitting so easier to solder, and grab hold off. You can get panel mounts or inline setups.

 

[GoldenBear]

Interesting...I've had someone also suggest 1/4 jack.

Would be quite easy to mount a barrel type input into the side of a fridge and then a jack onto the wire from the controller.

 

[QldKev]

Interesting...I've had someone also suggest 1/4 jack.

Would be quite easy to mount a barrel type input into the side of a fridge and then a jack onto the wire from the controller.

ImageUploadedByAussie Home Brewer1436405715.137224.jpg

Don't stress which one too much, the small difference can be offset in the calibration if needed. I've got one of mine setup using a small headphone jack, I meted the first one soldering it though. I don't have an electronics type soldering iron. Pick which ever one appeals to you the most.

 

[klangers]

A good connection should have ~0 resistance when compared to the massive internal resistance of the probe itself.

I would suggest using plugs than can be sealed against moisture so corrosion doesn't become an issue (this WILL affect your readings). There are heaps of plugs specifically designed for control system connections... all the above are originally designed for operation in a dry environment. That said, you can get XLR plugs with a rubber gasket. Take a walk through Jaycar and see what's what.

I've spent a number of years doing home recording studio stuff (combined with home brewing this makes for VERY expensive hobbies!) and I can vouch for the continued reliability of XLR plugs. RCA and TRS (1/4" or 1/8") are horribly unreliable in comparison.