The Weller WCC103 temperature sensor is actually an iron-constantan
thermocouple (possibly Type J), although Weller used Type K thermocouples
for its EC station series .
Sensitivity believed to be about 50 µV/°C
The relationship between temperature and voltage produced is NON-Linear.

What is a thermocouple sensor?
A thermocouple is a sensor for measuring temperature. It consists of two
dissimilar metals, joined together at one end. When the junction of the two
metals is heated or cooled a voltage is produced that can be correlated back
to the temperature. The thermocouple alloys are commonly available as wire.

When replacing the WCC103 sensor the leads MUST be correctly installed or
the iron stays on continuously and eventually overheats.
The Iron (magnetic) lead connects to the RED wire
The Constantan (copper-nickel alloy/non-magnetic) lead connects to the
YELLOW wire

gb

"gb" wrote in message
...
This is an informational post for owners of the Weller WCC100 soldering
station.
Some Elecraft builders have used this soldering station for building their
kits.