Innovate Motorsports TC-4 - Manual (Page 5)

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4. Connecting the TC-4
The TC-4 looks like this:
4.1 Connecting power
Connect switched 12V power (switched on when the cars ignition system is on) from the car to
the terminal marked 12V on the TC-4 connector.
Connect one of the terminals marked GND to a good ground on the car. The engine block will
supply a good ground connection.
4.2 Connecting Thermocouples
One thing that is counter intuitive for many people is that the negative side of a thermocouple
wire is always red. There are many different types of thermocouple wire; types K, J and T being
the most popular. All have a red negative lead and a yellow, black, or blue positive lead
respectively. When connection the thermocouple to the terminals on the TC-4, be sure to
connect the yellow lead to the + and red lead to the - terminals.
Several manufacturers offer EGT "thermocouple probes" which are actually inserted into the
exhaust gas stream through a hole in the headers or exhaust manifold. These provide a more
accurate measurement of exhaust gas temperature. They are commonly available in types K
and J. Only type K will currently work with the TC-4. To use a thermocouple probe, connect the
red and yellow leads of the thermocouple wire to the yellow and red leads of the thermocouple
probe. The junction is inside the probe. You can not use normal copper wire to connect the
thermocouple probe to the TC-4. You must use thermocouple wire to connect the probe. If you
do not, there will be an extra two-metal junction where the Copper wire meets the wires of the
probe. This extra junction will cause a large error in the temperature readings.