Multiple RTD question

[mizzourah]

Is there anyway to hook multiple RTD's to something like this

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or this

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via a switch (something like 4-6 position rotary switch)? I know this is not necessary but I want a digital readout at multiple spots without having to have a connection to a PID and possibly one to my fermenter just to monitor temps.

Does anyone know if this is possible?

 

[mgude]

I am curious about this as well. I am planning a system that uses a single PID to control the HLT and BK, but it would be cool to have one (or more) if these cheap temp readouts to keep track of the MLT, wort chiller, herms output, etc.

I hope someone smarter than me answers you!

 

[shortyjacobs]

A 3PDT switch will let you flip between two of them:
http://www.amazon.com/dp/B006LU4HIY/?tag=skimlinks_replacement-20


If you gang three of those switches together, you could flip between four RTDs, (your temp readout goes to the middle of switch one. Switch one's outputs go to the middles of switches 2 and 3. RTDs connect to the outputs of switches 2 and 3....so switch 1 is your A/B switch, switches 2 and 3 give RTDs 1,2,3,4. For RTD 1, you want "A-1", RTD 2 is "A-2", RTD 3 is "B-1", RTD4 is "B-2).

Here's a 3 position, 4 pole switch:
Amazon.com: Rotary Switch 4 Pole 3 Position: Automotive

That would give you 3 RTDs on one switch, (1 pole unused), I believe.

Here's a 3 pole, 4 position one:
Rotary Switches

Just search "3 pole x position switch" where X is the number of RTDs you want to have, and you'll find some on the internet.

Damn near any switch will work...RTDs carry practically zero current, so no worries about current or voltage specs.