Some other things (sorry if preaching to the choir as you are pretty onto stuff usually).
1. You haven't accidentally reversed the wiring somewhere?
2. If using connector systems (plugs) they recommend running TC extension wire from the connector to the PID and this has to have correct polarity.
3. Did yours come with the wires at the end twisted around each other? The ones I have have 2 separate wires that are individually insulated until right at the end where they join. With yours being twisted at the end it puts the wires in contact at several points and is this messing with the voltage? Prob not but just a thought.
I got mine from
http://www.tcdirect.net.au/deptprod.asp?deptid=180/21
Also maybe one is just a dud? But it seems it works sometimes.
I think Rich was saying that you are doing your tests with the thermocouples under pressure (as you would when pressing). Whether the pressure is somehow affecting your results. I don't know about how pressure would affect it electrically, but it could affect it mechanically ( eg pinching wires or creating a short circuit). Is that right rich?
Thermocouple positioning
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When I got the thermocouples the had a threaded fitting on the end. I cut it off and welded the wire ends together. I have been thinking about the twists all day and I think that might be my issue.falls wrote:Some other things (sorry if preaching to the choir as you are pretty onto stuff usually).
1. You haven't accidentally reversed the wiring somewhere?
2. If using connector systems (plugs) they recommend running TC extension wire from the connector to the PID and this has to have correct polarity.
3. Did yours come with the wires at the end twisted around each other? The ones I have have 2 separate wires that are individually insulated until right at the end where they join. With yours being twisted at the end it puts the wires in contact at several points and is this messing with the voltage? Prob not but just a thought.
I got mine from
http://www.tcdirect.net.au/deptprod.asp?deptid=180/21
Also maybe one is just a dud? But it seems it works sometimes.
I think Rich was saying that you are doing your tests with the thermocouples under pressure (as you would when pressing). Whether the pressure is somehow affecting your results. I don't know about how pressure would affect it electrically, but it could affect it mechanically ( eg pinching wires or creating a short circuit). Is that right rich?
It's still strange that I got pretty accurate results when I butted the wire ends to the cassette rather than laying them flat.
Btw I appreciate any help. Never to proud to admit when I am wrong and I clearly did something wrong here. ;-)
Last edited by gozaimaas on Sun Nov 10, 2013 5:01 pm, edited 1 time in total.
Electrics aren't my thing, but what falls is saying is sensible, it ties in with the outline described per the second document:
http://www.beesindustrial.com/docs/Grou ... ouples.pdf
http://labjack.com/support/app-notes/thermocouples
Per the photo above, the way the thermocouples are inserted will have sparks flying if you press like that. Earthing the press is a good idea (essential).
Cheers falls, the slight buzzing my press has is called a ground loop ... who knew )
http://www.beesindustrial.com/docs/Grou ... ouples.pdf
http://labjack.com/support/app-notes/thermocouples
Per the photo above, the way the thermocouples are inserted will have sparks flying if you press like that. Earthing the press is a good idea (essential).
Cheers falls, the slight buzzing my press has is called a ground loop ... who knew )
http://www.omega.com/techref/das/tcshort.html
Some advice from omega
Some advice from omega
Don't wait up, I'm off to kill Summer....
