Different readings with Helix vs Ranco??

Hi Everyone, I recently got my Ranco backup all in place. I have a Helix DBS 1000 controlling my racks and a Ranco ON/OFF placed in front of it in the circuit as a backup. I have the probes for the two thermostats placed in almost identical spots on the Flexxwatt and the Ranco reads 4 degrees cooler than the Helix?! Anyone experienced anything similar?

JonV

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Originally Posted by nevohraalnavnoj

Hi Everyone, I recently got my Ranco backup all in place. I have a Helix DBS 1000 controlling my racks and a Ranco ON/OFF placed in front of it in the circuit as a backup. I have the probes for the two thermostats placed in almost identical spots on the Flexxwatt and the Ranco reads 4 degrees cooler than the Helix?! Anyone experienced anything similar?

JonV

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Do you have another accurate way to measure the temp where the sensors are?

Yeah, I temp-gunned it and I think the helix is right on and the ranco is off. It's not a big deal, I can just set my temps realizing the ranco will always be 3-4 degrees cool.

JonV

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Originally Posted by nevohraalnavnoj

Yeah, I temp-gunned it and I think the helix is right on and the ranco is off. It's not a big deal, I can just set my temps realizing the ranco will always be 3-4 degrees cool.

JonV

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Thats what I was thinking, Bad resistance in the wiring or internally in the unit might be causing a bad reading. Good thing you know its off! Lesson here is that you should never trust one temp reading if at all possible!

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Originally Posted by the bull

Thats what I was thinking, Bad resistance in the wiring or internally in the unit might be causing a bad reading. Good thing you know its off! Lesson here is that you should never trust one temp reading if at all possible!

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I also find that the probe for the Ranco is a lot thicker than the probe for the Helix...maybe it's too much insulation around the probe? Or could the 8' wire itself be picking up on ambient temp and thus reducing the reading?

JonV

Something that's helpful is to use your tempgun on a mercury thermometer to see how far it is off. Then you can get the error of the unit pretty accurately.

It might be the case that the tempgun and the helix are off that much and the ranco is on. My ranco's actually run hotter than my probes and thermostats...... (ralph davis's latest youtube video also notices the rancos running hotter for his incubator)

Maybe your unit if off?

Did you give the Ranco a chance to equalize temps? Leave it sit next to the helix for a couple hours to get the probe to be all one temp. Then base it off known to be accurate thermometer.

The mercury thermometer is a good idea for taping to a probe and varifying accuracy, but due to a little thing called emosivity and the fact that mercury and glass is very low on the emosivity scale it is not a good idea to try shooting the thermometer with a temp gun to verify accuracy of the temp gun.

Do you mean emissivity?

I just recall reading that a good way to "sync" your tempgun is to get a reading on a mercury thermometer that has had time to adjust to room temps.

Maybe this was in barker's book? I don't recall where or how I got started doing it.....

Thanks!

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Originally Posted by jpman78

Do you mean emissivity?

I just recall reading that a good way to "sync" your tempgun is to get a reading on a mercury thermometer that has had time to adjust to room temps.

Maybe this was in barker's book? I don't recall where or how I got started doing it.....

Thanks!

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Yes, sorry I was in a hurry typing that and spelling never was one of my strengths. I'm an engineer, I don't have to know how to spell just calculate! :D

Now if you put a piece of black electrical tape on a surface and put the mercury thermometer on it also then you could use it as a reference to see how accurate your temp gun is. With that said though you have to do an emissivity check and set your gun (if it is the kind that can have the emissivity set on it) to the proper setting before taking the reading of that material. Also the angle of the reading will effect it also, so you have to make sure you take readings at the same angle at all times.

With that said it is probably more of a pain than most people are willing to do! I guess that is why my wife thinks I'm a little retentive when it comes to making sure temps are perfect! :weirdface