EGT is very useful in tuning an engine for maximum reliability. Measuring EGT's is a good way to tell if ignition is advanced too much or too little, or to see that fuel trim is too rich or too lean. Genboard provides two optional EGT channels, both which can be used with either K- or E-type thermocouples.

The sensor tip is placed in the exhaust, before the turbo, relatively close to the exhaust port. Only the sensor tip is in the exhaust stream. The cable end must be kept at much lower temperature. Keep the cable connection below 400C. Consider this when mounting.

The wiring configuration for an EGT sensor is limited; easiest way is to place the cold junction at the circuit board at the AD597 chip which amplifies the EGT signal.

Calibrate config.egt1_offs for proper reading of board temperature with K-thermocouple inputs shorted (without thermocouple attached). Because ADC hardware is 12 bit, resolution is 5000mV/4096, the theoretical calibration value with a WebShop standard sensor is 5000/4096 / (10*75 / 175) * 256 = 73 = 0x49

egt1_cal=0x49

Read below for the explanation of (10mV * 75 / 175) level. The 256 multiplier is needed because of an internal scaling constant.

The calibration has to be verified: see if temperature read matches input voltage (measured with DVM DC 200mV).

Place sensor tip into natural gas flame, and get multimeter reading. Eg. Reading of 27mV when glowing hot. Reference temperature 27C room temperature. Calculating with 40uV/K it means : 27C + 27 mV / (40uV / C) = 677 C

To configure and test the exhaust gas temperature measurement, one must know the signal levels in the system: