Pyrometer

[meby]

I found this on ebay. Can you say pre turbo and post turbo. Anyone see a reason why I shouldn't buy one?


http://cgi.ebay.com/ebaymotors/ws/eBayI ... MEWAX%3AIT

[Ace]

I'd ask where the lead wires are. They are a matched set and need to be of a certain length.

[dpuckett]

I'd say if the lead wires are the same length, you'd be ok.

Ace, am I wrong?

DP

[meby]

Thanks, i'll ask.

The only other thing that might be an issue is its a 3" gauge. So far I haven't been able to find any mounts. They are either 2, 2 5/8, 3 3/8 or 5".

[Begle1]

The "matched set" thing is overblown. I've done experiments and set-ups with temp controllers, thermocouple wire, probes and gauges, and while differing the wire several feet will cause a few degrees in temperature variation, I've never seen a variation that would be noticeable on a 0-1500 degree gauge face.

I have digital thermocouple displays in my truck, the difference between a few inches of Type K thermocouple wire and 30 feet of Type K thermocouple wire is about two degrees.

The right way to do it is to route the thermocouple to a "thermocoupler" and convert it to a linear 0-5 volt signal as soon as possible, but there are thermocouple extensions wires and plugs sold and used gleefully by many.

[meby]

Were do I buy leads if the ebayer doesn't have them? Any place that sells pyro's?

[Ace]

...and while differing the wire several feet will cause a few degrees in temperature variation...

How do you read a few degrees on a gauge that covers 100 degrees across a sweep of 1/4"?

[Begle1]

With digital temperature controllers and data loggers.

[Ace]

Well then, if you are not seeing much temp variance on a pyro with "several feet" of wire missing, my guess would be you have misacalibrated or otherwise mis-configured your digital temp controller.

[Begle1]

I must've misconfigured the boiling point of water too then.

Hmm, weird.

[Philip]

I have worked with type K thermocouples a lot. Type K wire isn't sensitive to length differences.

[93_Fummins]

Buy it, Try it, and tell us how it goes!

[Ace]

Quoted from Autometer installation instructions:

2. With the probe installed, the wire harness can now be routed to the gauge. The wire harness is an integral part of the pyrometer
calibration. It may not be shortened or lengthened without affecting the gauge calibration."

[93_Fummins]

I have worked with type K thermocouples a lot. Type K wire isn't sensitive to length differences.

Depends on what is reading the output, and just how much difference in length there is.... But, you are right for the most part, Type K isn't as sensitive as others.

[Ace]

I guess it just depends on how comfortable you are with the the sensitivity and accuracy of the equipment. Water boils at what, a little over 200 degrees? Exhaust temps can run up over 10 times that.

Whatever.