Pyro Question

[LEPage]

I have a DiPricol Pyro & a PMCR both connected to the same thermocoupler. It has worked fine for nearly 3 years like this. All of a sudden the PMCR shows temps like 31* & the DP reads less than 100* all the time. Any suggestions on where to start my search?

 

[mattymac]

Could be a bad thermocoupler. My TST will read 31 if the motor isnt running. I used to have two EGT's hooked up to the same thermocoupler and after tapping a second hole I noticed that the readings are warmer in the mid range (around 6-900 deg) with two TC's. They read in micro ohms so its not a good idea to have them both hooked into one TC because it does throw the readings off a bit.

 

[Bob4x4]

T/couples produce a mili volt signal



Bob

 

[TMarszalek]

When you use a single thermocouple, make sure you use thermocouple wire to hook up your external devices, such as your EGT gauge and PMCR. The Law of Dissimilar Metals will cause an error if you don't, and since this is a millivolt signal, a small error causes a big difference in the temperature reading. The thermocouples are Type "K", so you need Type "K' thermocouple wire. If one of the two devices are working properly, the thermocouple is good. You either have a bad connection or your wire has broken. Connecting a single thermocouple to two devices in parallel will not cause a problem since the millivoltage stays the same in a parallel circuit! The T/C (thermocouple) will read the ambient temperature, so if the engine ain't runnin' and it's 50 degrees in your garage, then the millivolt equivalent coming from that Type "K" T/C will be 50 degrees!

 

[Kday]

So you guys are sure I can hook up my new Juice Att thermocouple wire along with my analog guages safely and accurately?