JPI EGT probes: proprietary or universal?

Fearless Tower

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Fearless Tower
Anyone know if you can take an EGT probe connected to an EDM 700 and disconnect it from the unit and reconnect it to a single Alcor type EGT gauge?

I have an EDM that may need to be sent off for service (stuck in scan mode - the control buttons don’t seem to work) and I was wondering if I could wire one of the probes to an Alcor EGT gauge in the meantime?


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I had Alcor in my Glasair and I was told I needed new probes for the JPI because the Alcor wouldn't work with the JPI. Don't know what's the difference between them though.
 
I've never tried swapping probes between brands, but all the EGT probes I've seen are simple k type thermocouples and are not anything special.
 
JPI uses type K for both CHT and EGT. I think the Insight CHT are type J.

I have a JPI in my plane, and read some piece of JPI propaganda a while back where they made a big deal about incompatibility, but I don't see any reason not to try it with the Alcor for EGT. Absolute values aren't that important for EGT anyway.
 
Measure the resistance of the probes. (It will be low - like 5 ohms). If they are similar it might work although calibration may be an issue.
 
Measure the resistance of the probes. (It will be low - like 5 ohms). If they are similar it might work although calibration may be an issue.

Calibration is not a concern when it comes to thermocouples, at least in most cases. I'm under the impression that altering the lead length on the self powered instruments (such as the Alcor mentioned here) can have an effect on accuracy but considering the temps are relative and that all the Alcor gauges I've seen have never had temperature numbers on them I doubt it will matter much.

It is a very rare day that we actually dry block a thermocouple in the test lab in which I work and when we do, I would only trust the measurements taken at temperatures near the temperature we calibrated the thermocouple at.
 
JPI probes are not universal. Do some research on their site. They may be k or j but jpi uses grounded or ungrounded, not sure, probes and everyone else uses the opposite of jpi.
 
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