There are "zero degree (celsius) chips that generate a compensation
voltage referred to the ambient temperature like the comprensation part
of the thermocouple, AD makes them an LT too.

Frank

Bill wrote:

I have a digital multimeter that measures temperature with a "type K"
thermal probe. I believe this is a chromel alumel thermocouple.

A thermocouple normally generates a voltage which is proportional to the
difference in temperature between two junctions. In the lab if one junction
is held at a know temperature, usually iced water, and the other junction is
held at the temperature to be measured. The temperature difference between
the two junctions generates a small voltage that is proportional to the
difference between the two junctions.

Ok so what does the multimeter do to control the reference temperature? The
multimeter is at used in varying ambient temperatures so it would seem that
there must be some for of compensation going on. Any ideas how this works.

My experience with this unit is that it is not very accurate around normal
ambient temperatures.

Bill