Thermocouple Readings Sky High


 
That meter will measure capacitance. so if you have some loose caps you can measure you can at least figure out if mouser made a mistake...

Turn the meter dial to the capacitor symbol -| |- and then put your leads across a cap (out of circuit) and wait for the value to settle, should be as simple as that. Then you've just got to read and interpret the result....
 
Looking back at your soldering job and nothing stands out bad, nothing at all. In fact it looks great. So, its something we can't see, a bad component, and solder bridge under a component that is just touching enough, but as it warms up its fine. Im just grabbing at straws here, lol.

If you want, I could do an adapter board for ya, shipping shouldn't be that much. You would need to add some wire work to your board to get it set up. Judging from your soldering skills that should be a problem.
 
Yah, that's why I asked if he used flux on the board when he soldered the TC chip, cause flux under the chip can sometimes lead to near bridges under the chip that you could never see.

SMD stuff doesn't need the bump of solder like that, the connection is under the pin not on top....


So I suggest that some of that excess solder be pulled off the TC amp legs with solder wick dipped in flux and hoping that reflow and lightening up on the solder might clear up whatever is going on here... (wash the board again when done, wash it good)

To be clear, I am not suggesting re-flowing the solder, like touching up or adding solder to make sure a connection is good... I am talking about REMOVING solder so each pin has just a light coating of solder remaining...
 
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RalphTrimble said:
Yah, that's why I asked if he used flux on the board when he soldered the TC chip, cause flux under the chip can sometimes lead to near bridges under the chip that you could never see.

SMD stuff doesn't need the bump of solder like that, the connection is under the pin not on top....


So I suggest that some of that excess solder be pulled off the TC amp legs with solder wick dipped in flux and hoping that reflow and lightening up on the solder might clear up whatever is going on here... (wash the board again when done, wash it good)

To be clear, I am not suggesting re-flowing the solder, like touching up or adding solder to make sure a connection is good... I am talking about REMOVING solder so each pin has just a light coating of solder remaining...
Click to expand...

Hi Guys,

Sorry for late response, I was on slight sleep shift and just woke to my first alarm to check on the progress of things. It's now 2:30am and things are looking nice and steady. It seems I'm currently experiencing the legendary stall...

http://postimg.org/image/9k1sgiwhz/

I've checked the temperature against my known source and it's still bang on, so it certainly seems once things have stablised it holds an accurate temperature. Extremely bizarre indeed! Ralph, I did use some flux during the solder, but not much, and on both occasions I scrubbed things thoroughly with alcohol afterwards - I'm pretty confident there are no bridges on top of the board; internally is another questions entirely...

John, your offer of a board is very kind, I'd certainly be interested in discussing this further as I'm really not confident in things as they stand - regardless of how reliable it appears right now.
 
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