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# Need Urgent Help for MAX 6675

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#### tiemin

##### Newbie level 1
max6675

Hi, all,
I'm trying to integrate Max 6675 into one of the important project. We build a circuit according to MAX 6675 data sheet. However, we found that the output were wrong.
It was 70 degree. While, the resistance of the thermocouple is around 500 ohm.
For another thermocouple, the resistance is around 300 ohm, the output was 50 degree.

Note: we use K type thermcouple. If we use Fluke 17B to test them, all of them work. The reading of the 17B were around 26 degree, which is the temperature of the room.

Actually, the thermocouple is around 1m. So, we cut it and just remain 2cm with the tip of the thermocouple. Now, the resistance of the piece is aournd 4 ohm. While, the output become a right one, around 26 degree.

So, my question is, will the resistance of the thermocouple impact the output of MAX 6675? If the answer is YES, do you have any suggestion to solve the problem. Actually, we need the length of the thermocouple around 1m. Since the diameter of the thermocouple is just 0.1mm, it is not easy to solder it to a copper wire.So, we want to keep the thermocouple as it is.

Laurence

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