Changing the pulse count for rpm

[eddies]

Hi guys

How do I change the pulse count for rpm, at present my tachometer is displaying twice the rpm value. I have a lycoming io-180 with a g3i CID ignition that is supplying a square wave pulse count.

Many thanks
Eddie

 

[russdent]

Use the Engine Information Wizard (SETUP MENU > EMS SETUP > ENGINE INFORMATION).  Change the pulse count to .5 and that should do it.

FWIW, my rpms got really erratic above 2550 with the G3i so I switched to a Westach 303 DGT sender on a low voltage input.  The side benefit is that I don't lose the rpm display when I switch off the G3i for mag check at runup (or if the G3i failed, I wouldn't lose my tach).

 

[eddies]

Thanks Russ,

I'll have a go at changing the pulse count.

Guess I'll have to wait till I do the final assembly to see if I have the same issues with the G3i

Cheers
Eddie

 

[russdent]

Hmmm, I'm almost afraid to say anything. Right after my post the Westach DGT sender seized and chewed up the drive tang. It was in service less than a year.  I promptly replaced them but rpms were not accurate between 1200 and 1600 rpms. We pulled the seized unit apart to see how it was built and it didn't look like something I wanted in my airplane. Sooo...

Now I have a UMA hall effect tach sensor running off +12V regulated supply and the tach shows accurate and rock solid at all rpms.       pulses/rev=1

Third time's a charm I hope.
Russ

 

[jakej]

Russ

That's how we all learn, from others or our own experience

Good to get the feedback, thanks.
Jake J