Can you "bench test" a pyrometer?
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From: Minnesota
Can you "bench test" a pyrometer?
Mine acts up, once in a great while, like it loses power, then comes back. Autometer Pro Comp pyrometer. Been through the wiring twice, cannot find anything wrong. Could it be the gauge??
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From: Cabot, Arkansas
To test the gauge unhook the thermocouple leads from the gauge but leave the 12v. power applied. If the gauge now reads ambient temperature it is working.
Bench testing the thermocouple itself is not an at home deal. You can apply heat to the probe and measure for milivolt deflections, but there isn't any way to get an accurate measurement.
Most of the time it is the thermocouple that fails, not the gauge.
Bench testing the thermocouple itself is not an at home deal. You can apply heat to the probe and measure for milivolt deflections, but there isn't any way to get an accurate measurement.
Most of the time it is the thermocouple that fails, not the gauge.
Last edited by cookie88; Apr 25, 2007 at 06:06 PM.
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When I installed my ProComp pyro,I was having a problem.It turned out to be a bad probe,but long story short an autometer rep that I talked w/ said leave the 12v power and ground connected,undo thermocouple leads,and turn yor ignition on,if the guage reads between 32* and 100* the gauge is fine.If the gauge tests good,pull the probe and with a friend hold a cigarette lighter to the probe while your friend watches the gauge.If working proper it should read around 350*.The autometer rep. also said when testing the probe make sure the probe wasn't grounded.I'm not really sure why this is seeing as how it's mounted to a metal exhaust pipe?Hope this helps
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From: Reno nv
Originally Posted by cookie88
To test the gauge unhook the thermocouple leads from the gauge but leave the 12v. power applied. If the gauge now reads ambient temperature it is working.
Bench testing the thermocouple itself is not an at home deal. You can apply heat to the probe and measure for milivolt deflections, but there isn't any way to get an accurate measurement.
Most of the time it is the thermocouple that fails, not the gauge.
Bench testing the thermocouple itself is not an at home deal. You can apply heat to the probe and measure for milivolt deflections, but there isn't any way to get an accurate measurement.
Most of the time it is the thermocouple that fails, not the gauge.
place the probe tip in a 500 degree stabilized oven and just touch the rack for a moment or so until meter says what oven is set to more or less. oven will probably be up to 100 degrees off high or low
1950 which is what methane on your gas stove burns at. put the just tip in the blue part of the flame and let sit there for no more than a minute unless the meter does not go higher than 1500. Sorry I don't remember what propane burns at.
be careful all these temps can produce a nasty burn rather quickly.
the tips ARE rather fragile and living in an extreme environment, so the service life may not be all that great.
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From: Cabot, Arkansas
Originally Posted by piotrsko
actually there are several tests: 212 (boiling point of water)
place the probe tip in a 500 degree stabilized oven and just touch the rack for a moment or so until meter says what oven is set to more or less. oven will probably be up to 100 degrees off high or low
1950 which is what methane on your gas stove burns at. put the just tip in the blue part of the flame and let sit there for no more than a minute unless the meter does not go higher than 1500. Sorry I don't remember what propane burns at.
be careful all these temps can produce a nasty burn rather quickly.
the tips ARE rather fragile and living in an extreme environment, so the service life may not be all that great.
place the probe tip in a 500 degree stabilized oven and just touch the rack for a moment or so until meter says what oven is set to more or less. oven will probably be up to 100 degrees off high or low
1950 which is what methane on your gas stove burns at. put the just tip in the blue part of the flame and let sit there for no more than a minute unless the meter does not go higher than 1500. Sorry I don't remember what propane burns at.
be careful all these temps can produce a nasty burn rather quickly.
the tips ARE rather fragile and living in an extreme environment, so the service life may not be all that great.
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Joined: Feb 2006
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From: Tennessee
You know, I'll not be able to add anything as to whether or not you can bench-test one, but I think I had one go bad in my previous truck.
After about 8 mos of service, occasionally (usually on start-up) the gauge would peg- out at 1500. then after a minute or two, it would go back to normal.
Eventually, it got so weird that it would just bounce all over the place.....all the connections were tight, I checked.
They were Isspro's.
Just FYI.
After about 8 mos of service, occasionally (usually on start-up) the gauge would peg- out at 1500. then after a minute or two, it would go back to normal.
Eventually, it got so weird that it would just bounce all over the place.....all the connections were tight, I checked.
They were Isspro's.
Just FYI.
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simply pull the probe heat it and read what the millivolts are. should be fairly acurate if you have a good multi meter
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From: CT
I had a problem with my pyro when I installed my gauges, I got sent the wrong probe, I got a grounded probe instead of the other type. Anytime the probe would come in contact with metal it would ground and the gauge would read below zero. I still sometimes have problems with it, just POS autometer I guess.
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From: Minnesota
Originally Posted by cookie88
To test the gauge unhook the thermocouple leads from the gauge but leave the 12v. power applied. If the gauge now reads ambient temperature it is working.
Bench testing the thermocouple itself is not an at home deal. You can apply heat to the probe and measure for milivolt deflections, but there isn't any way to get an accurate measurement.
Most of the time it is the thermocouple that fails, not the gauge.
Bench testing the thermocouple itself is not an at home deal. You can apply heat to the probe and measure for milivolt deflections, but there isn't any way to get an accurate measurement.
Most of the time it is the thermocouple that fails, not the gauge.
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From: Minnesota
Ok, I finally got to do some testing last night. Took the probe out and bench tested it using millivolts. Seemed to work fine, as I heated the tip with a torch, the voltage went up, and as it cooled down the voltage came down. Could not get it to act up. Then hooked it back up to the gauge, and heated the tip while watching the gauge. Worked perfect. I then removed the probe, and secured the leads from the gauge under the hood as I wanted to drive the truck with the probe unhooked. So this morning on the way to work I watched it like a hawk, and seemed to measure ambient temp. First started the truck it read 50 degrees, then as engine temp came up, the gauge came along with it, ending up at about 110 degrees, which I figure was underhood temp.
The only thing I can think of now is maybe it is getting some kind of interference. I did run an isolated ground a while back, which seemed to take care of it, but now it is back. Maybe I should run an isolated power wire as well?? I am out of ideas. Maybe solder all the connections?
The only thing I can think of now is maybe it is getting some kind of interference. I did run an isolated ground a while back, which seemed to take care of it, but now it is back. Maybe I should run an isolated power wire as well?? I am out of ideas. Maybe solder all the connections?
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From: Colorado Mountain Country
I had somewhat similar issues a year ago, check this out...
https://www.ford-trucks.com/forums/496142-my-pyrometer-is-possessed.html
It ended up being a bad sender/thermocouple. I'd hedge a bet that is your issue as well. Thank Scott (Cookie88) for the troubleshooting flowchart.
https://www.ford-trucks.com/forums/496142-my-pyrometer-is-possessed.html
It ended up being a bad sender/thermocouple. I'd hedge a bet that is your issue as well. Thank Scott (Cookie88) for the troubleshooting flowchart.
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From: Minnesota
Thanks k2.
After extensive testing, I ordered the new probe. This allowed me to drive 4 days with it unhooked while I waited. The gauge always read ambient temp, never faultered once. Got the new probe last night, and installed. Took it out this morning, and guess what, same thing.
The only conclusion I have now is a wiring problem, which I have been through twice. I think I am going to run an isolated power wire and see if that helps....
After extensive testing, I ordered the new probe. This allowed me to drive 4 days with it unhooked while I waited. The gauge always read ambient temp, never faultered once. Got the new probe last night, and installed. Took it out this morning, and guess what, same thing.
The only conclusion I have now is a wiring problem, which I have been through twice. I think I am going to run an isolated power wire and see if that helps....