Lightspeed Plasma III Digital Timing Display

[Dynon101]

Hi All,

I have read on another post of this forum that somebody was able to display the digital ignition output of a Lightspeed plasma 3 ignition systems.

If this is indeed possible and somebody has done it would you be so kind as to walk me through the wiring and The Wizard setup procedure?

I see that the output plug has b
pin number 3 and that is for digital timing output and that .01 volts is equal to one degree of timing.

I might wish to run out of gas so the variable timing output wiring might be something I would be interested in as well.

THANKS FOR THE HELP!!!

 

[cbennet12]

Hi,

I have attempted it with marginal success. The issue is that the Lightspeed outputs the values in microvolts and the Dynon inputs are not sensitive enough to accurately represent the correct value(s).

This is not a knock on the Dynon, that's asking a lot for the system to be that sensitive. And this is probably true for most or all other EFIS' out there.

The good news is that Flight Data Systems has a box available that will step up the voltages to a range that is measurable by the Dynon. This should give you accurate readings. I have the box but have not yet installed it so I cannot personally attest to it's performance.

It's on the home page of LightSpeed's web site.http://lightspeed-aero.com

Craig

 

[dynonsupport]

Craig,
If you are trying to deal with low voltages like 0.01V per degree, use a thermocouple input. These have amplifiers on the inputs that will give you tons of resolution on low voltages, no external box needed. We didn't realize this was an issue to the point someone had made a $100 box to solve it! The SkyView EMS has 14 thermocouple inputs so there are spares even on a 6 cylinder engine.

Since these inputs are differential, hook the lightspeed to one side of the thermocouple input and run the other to the ground point of the lightspeed.

 

[rogersmart]

I am ignorant on what this is, I have a light speed. Please explain what digital ignition output would be used for and how would it display. The only connection I have is engine RPM and it works great on my Dynon.

 

[vlittle]

Craig,
If you are trying to deal with low voltages like 0.01V per degree, use a thermocouple input. These have amplifiers on the inputs that will give you tons of resolution on low voltages, no external box needed. We didn't realize this was an issue to the point someone had made a $100 box to solve it! The SkyView EMS has 14 thermocouple inputs so there are spares even on a 6 cylinder engine.

Since these inputs are differential, hook the lightspeed to one side of the thermocouple input and run the other to the ground point of the lightspeed.

Aha! I used a GP input for my timing advance meter, but I've always been suspicious of the measurement because it was sensitive to ground potential differences. Using the TC input to make a differential measurement should eliminate this error.

I guess the result will be displayed in degrees as well!

V

 

[dougnlina]

I went through this on an older thread, although there are some work-arounds, the easiest thing to do is buy lightspeeds $99 converter to convert the advance to a 0-5V format (instead of millivolts) the converter can be found on their accessories page:
http://lightspeed-aero.com/Products/Accessories.htm

 

[shenweas]

I have successfully wired the timing and MAP outputs from the Lightspeed III ignition to Dynon.  If I remember correctly I used a C type input on the Dynon for timing and an A type input for MAP.

Below picture is the results from the data log uploaded to Savvy.

I checked to displayed timing against the actual timing using a timing light and if I remember correctly I had to calibrate it across the range a little in the Dynon code file....please don't ask me to dig it up  :'(