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spitfire9
11-25-2010, 12:36 PM
I have the start valve lights working on the LED64 card. They come on with the start switch and go out when the switch is released.

OK,, that works , but I was wondering about the primary pump lights. They should come on when the start switch is pressed ( like the start valve lights) but they should go out about 2 sec or so before the Start switch is released and the valve lights go out.
( this is for a Convair turboprop)

Is there a way I can use the same FS variable (engine start switch) for the primary pump lights BUT put a delay of a couple seconds on the valve lights or speed up the shut off of the pump lights. Have the pump light go out a couple of sec before the start switch is released ??

Thanks !

CocnutAir
11-28-2010, 11:24 AM
Did you try the timer component?

spitfire9
11-28-2010, 11:31 AM
Thanks for the reply.

I just nticed I still have .18 so I will install .21 and give it a try,, thanks.

spitfire9
01-09-2011, 12:09 PM
OK,, i got the timer to turn the light on with a delay but I can't figure out how to get the light to turn off before the start switch is turned of??

The start switch is held on for 8 sec. The primary pump light should come on when the start switch is engaged and it should turn off approx. 1 or 2 sec before the start switch is disengaged.

Could I use the timer function to turn the led off after 7 0r 8 seconds,, even with the starter switch still pressed??

Thanks in advance.
brian.

CocnutAir
01-09-2011, 05:38 PM
Another approach - instead of using a timer, alternative might be to use engine rpm to turn lights on and off - with start switch engaged.
i.e. Use range of engine rpm in conjunction with start switch state.

Is start switch magnetically-held or is switch disengaged manually?

spitfire9
01-10-2011, 01:13 PM
Sounds like a good idea,, to use rpm ! I will give it a try.

The start switch is held down maually. The primary pump light comes on for a few seconds during the time the start switch is engaged as a test function for the primary fuel pump. If that light doesn't come on,, start sequence is aborted because fuel will not be adequate for light up.

Thanks again!! I will let you know how it works.

P.S. Just thought of something. I will use an output for the start switch and an output for rpm on the circuit or else the light will come on every time I reduce power in flight??

CocnutAir
01-10-2011, 09:06 PM
As this is fuel pump, how about using fuel flow instead of engine rpm? There is an offset for fuel flow.