Will auber 2352 pid work without RTD attached?

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rknerem

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I just plugged my control panel in for the first time to see if everything powers up, and remarkably it did. My question is this, I dont have the RTD yet, will it work for my boil kettle on manual without any type of probe? It powered up and blinks numbers and letters alternately on top and bottom, Is this normal? I havent had a chance to go through the instructions yet for programming, I put them somewhere and need to find them.
 

Junkster

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If your RTD hasn't arrived yet, you can probably put a 100 ohm resistor between 4 & 5 to keep it happy temporarily.
 

zeno27

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You should also be able to short the thermocouple terminals and it should read the ambient temperature, if you select the input as TC (any type).
 

Dgonza9

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I'm in awe of you guys. I was going to suggest a bout of cursing and maybe trashing the room a bit. ;)

But I like your solutions better.
 

audger

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putting in a 100 ohm resistor between the two terminals, and setting the probe type to PT100, should make the PID read 32*F.

You should also be able to short the thermocouple terminals and it should read the ambient temperature, if you select the input as TC (any type).

its not going to read ambient temp just by shorting two terminals... thats why a sensor is required in the first place...
 
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putting in a 100 ohm resistor between the two terminals, and setting the probe type to PT100, should make the PID read 32*F.



its not going to read ambient temp just by shorting two terminals... thats why a sensor is required in the first place...

Right, and right/wrong. Shorting the terminals and setting the PID to thermocouple (TC) should result in 0°C / 32°F. I think the poster before you was stating that it would read 25°C (default ambient), not that it would actually be sensing anything.
 

zeno27

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putting in a 100 ohm resistor between the two terminals, and setting the probe type to PT100, should make the PID read 32*F.

its not going to read ambient temp just by shorting two terminals... thats why a sensor is required in the first place...

Thermocouples work based on a thermoelectric effect known as the Seebeck effect, wherein a conducting wire with a temperature gradient along its length develops a potential difference. Electrons diffusing and all that. Take two dissimilar conducting wires, join them at the "measurement junction," and you can measure a voltage difference on the "reference" ends due to a temperature gradient between the measurement site and the reference ends. However, in the absence of a temperature difference, there is no Seebeck effect and therefore no voltage or potential difference at the reference ends.

Shorting the thermocouple terminals ensures there is zero measured voltage, which the controller interprets as being no difference in temperature between the measured point and the controller. It has a cold-junction correction (typically an onboard thermistor or PRT) so that it can determine the ambient temperature, and it displays that. It would only display 32F/0C if there was zero voltage and the reference was being held in an ice bath.

Here are a couple of pictures illustrating what I am talking about. Notice the orange wire shorting terminals 9 and 10. Okay, its an Auber 2362, but I am willing to wager the 2352 works the same.

You DO NOT need a 100 ohm resistor to run the PID in manual mode, only a bit of spare wire.

photo_front.jpg


photo_short.jpg
 
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It has a cold-junction correction (typically an onboard thermistor or PRT) so that it can determine the ambient temperature, and it displays that. It would only display 32F/0C if there was zero voltage and the reference was being held in an ice bath.

Hmmm. I stand corrected. I just put a jumper across my thermocouple meter (Fluke 54II) and the meter read room temperature.
 
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