I buying a pyrometer which is beter electric or mechanical.

 

i didn't know there was a choice

 

Mechanical...hands down

 

Well I think mechanicals are better but i have may have a scewed opinion since I just installed some auto meter Phantom II's

 

I thought a pyro was nothing more than a material with a known thermal resistance curve value that voltage went through to reflect a value on a meter, whether that be a typical D'arsonval type meter or a stepper motor, or even some type of discrete device to display information to the user in a logical format (i.e. degrees)

 

that last comment made my brain smoke more than my truck...lol

 

I am in insturmentation, and there is no "mechanical" pyro gauge. There are thermocouples, and PRT's. Most are type "k" thermocouple, and it is an electrical device.

 

So, how does a self-powered EGT gauge like a Westach or DiPricol (old style) work?

Does the heat on the thermocouple create voltage to move the gauge? It works, whether hooked up to power or not. On my Westach, 12v is for boost to function, but the EGT always works.

As to which is better? I dunno, the most accurate is a SPA digital. It's super cool, as you can choose how fast to average the values. You can have lightning fast response or slow depending on what you're after...

 

Yes a thermocouple does create a small amount of volts...actually millivolts.

Funny...you know I have dealt with electronics for a long time and had always thought a thermocouple worked differently than it actually does.

Thanks guys for making me go read up on it...I guess since I had never actually used one in anything until my Dodge came around I misunderstood how they worked. So I guess just when you think you know it all it turns out there is ONE thing you didn't.

 

by the way, those that might want to know more about thermocouples, might find this a nice read [evilgrin]
http://www.madsci.org/posts/archives...3814.Ph.r.html

 

There is only 1 truly mechanical EGT gauge and just about nobody runs one. I'm sure it would be relatively slow to respond.

All other EGT gauges are electric/digital...even if they have an analog display. With the analog gauges the digital signal has to be converted to move the needle. Analog gauges are definitely slower to respond than digital readouts.

Like mentioned above, the SPA EGT gauges are the most accurate and fastest responding. There was a test done a few years back that compared all the common EGT gauges. You can find a link to it by searching this forum.

 

Wasjsha who?... what?