Microlighters

I need some help! I am fitting a dual EGT gauge to a Rotax 503, plus 2 new probes.

The pins on the gauge are numbered 1, 3, 4 and 5. No's 3 and 4 pins are close together and I am guessing that 1 and 3 are for one meter and 4 and 5 are for the other one??

Each probe has a red and a yellow wire and my guess is to connect the yellow wires to no's 3 and 4 and the red wires to no's 1 and 5 ??

Roy

Those are the K type probe. The yellow is "+" and the red "-" My Guess would be that the 2 that are close together are the red wires and the other 2 are the yellow. The only thing that will happen if you have them wrong way round is that it won't work. Take a lighter and heat the probe a bit and see what happens on the gauge.

Thanks, KFA, I have now established that 1 and 5 serve one meter and 3 and 4 the other one. A bit surprising! I did this using a multi-tester set to measure resistance - could have done it with a battery too.Tomorrow I will connect the probes and apply some heat to them and establish which way round the wires go.
Thanks for your help.
Roy

I connected up today and applied heat to the probes and can now confirm that the yellow wires go to pin no's 1 and 3, and the red wires to pin no's 4 and 5. As I said above, pins 1 and 5 serve one meter and 3 and 4 the other one.
So all is well now!
Thanks again,
Roy

Le Pou wrote:I connected up today and applied heat to the probes and can now confirm that the yellow wires go to pin no's 1 and 3, and the red wires to pin no's 4 and 5. As I said above, pins 1 and 5 serve one meter and 3 and 4 the other one.
So all is well now!
Thanks again,
Roy

Thks for sharing. Now I also know

Le Pou wrote:I connected up today and applied heat to the probes and can now confirm that the yellow wires go to pin no's 1 and 3, and the red wires to pin no's 4 and 5. As I said above, pins 1 and 5 serve one meter and 3 and 4 the other one.
So all is well now!
Thanks again,
Roy

Thanks for sharing but it would be nice to know the make of guage and probe type. Stephan mentioned K-type for the probe...the guage?...Skdat or MGL or?

I use an MGL-TC2 with K-type probes and with them Red = minus and yellow = positive. I downloaded the installation manual from MGL's website. Just a note...the probes put out milivolts when heated. So you need an accurate/sensitive multimeter to measure their output. Also, never cut the probe leads shorter. They form part of the probe itself. One lead, the positive one, is made from cromel and the other from alumel. Therefore, it is very difficult to solder extension wires onto these leads and the joint gives trouble after a while. I used small terminal block clamps, so that I can remove the probes when I have to replace them. Crimp clamps will also work.

Hi Paul,

Thanks for the info. My gauge was given to me, it is a 2 1/8" dual analogue meter, make unknown, possibly Chinese. I got the probes from Skydat. They are the screw in type. I have connected them with the crimped connectors which I also got from Skydat.
I had no idea that there were so many options!

Thanks again,
Roy

Hi Le Pou,

Only a pleasure. Just make sure your gauge is matched to the K-type probes. From the graph you can see the output per degree centigrade is different. K-type = 41µV/˚C and the other popular one, J-type = 50µV/˚C.

Safe flying