Simple CHT/EGT Readout for Paramotor

This a cheap and simple DIY Monitor for Cylinder Head and Exhaust Gas Temperature for a Paramotor. It cost about £25 to build in the UK

You need
1 no K TYPE 6MM THREAD THERMOCOUPLE PROBE TEMPERATURE MEASUREMENT SENSOR 0-800℃ 1M
1 no CHT K type Thermocouple Temperature Sensors for Cylinder Head Temperature (14mm)
1no Maplins project box
1 no Maplin Rectangular illuminated rocker switch N84JZ
1 no Thermocouple Red Digital LED 0-999C Temperature Thermometer Panel Meter Display
1 no Thermocouple Blue Digital LED 0-999C Temperature Thermometer Panel Meter Display.

Should you choose to build this you do so, entirely at your own risk.

Here is a simple project to provide a cheap Cylinder Head and Exhaust Gas Temperature read out for a paramotor engine. You wont need any programming skills just basic assembly of purchased parts and rudimentary electrical skills. The system works at 12v so is most easily applied to Paramotors with starter motors running 12v (or close to 12v) batteries. However it could be used with a stand alone 3S Lipo power supply

If you don't have access to welding equipment you will need to take the exhaust header to your local welder to have an M6 nut welded in place

Parts

2No Digital displays with sensors

CHT sensor

EGT Sensor(optional if item supplied with display not suitable)

Suitable Project Box (something like this)

Suitable Switch(something like this)

Flex

Sheathing

1. Drill a hole in the exhaust header and weld or have welded an M6 nut to take the sensor. I actually built up some weld material and then drilled and tapped it at M6. Location about 100mm from Exhaust port. Check the thread for the EGT probe carefully. It is M6 on the probe that comes with the display, but some other slightly coarser thread with the wire sheathed one. The threaded pieces are inter-chageable from one probe to the other.

2. Run (or at least work out their lengths of) the cables from the Spark plug, the Exhaust header and power supply through the sheathing. Zip tie the sheathing to make sure there are no loops to get caught, ensure there is sufficient slack in the sheathed cables where they cross articulated joints eg the swinging arms. You can fix the display to the swinging arm somewhere you can see it or allow slack for it to go into a flight deck.

3. Cut openings in the box and install the displays,
4. Similarly install the switch.
5. Drill a hole for the cable entry
6. Connect the power supply through the switch to the display terminals. At the other end connect the power supply through a suitable plug and make sure you fuse it
7. Connect the sensor cable direct to the displays. Hint:- if the display goes the wrong way, ie decreases when heated, simply swop the sensor wires between terminals on the back of the displays
8. Secure the sheathing into the box with some hot glue.

If you want to make the whole thing smaller you could use a single display and a changeover switch to switch the sensor that is connected to the display.