alt out light

[prkaye]

I have the PlanePower alternator, which has a lead for an alternator-out light. I have this connected to a lamp on my panel. My question is, under what conditions does it activate? I am beggining to test my electrical system with a couple of 6V flashlight batteries in series. When I hook this battery up and turn on the BATT switch, my alternator-out light illuminates. When I then turn on the ALT switch, the alternator-out light remains illuminated. Is this to be expected? Does the light illuminate based on the output voltate of the alternator (which would be zero when the engine is not running, I guess) or is it determined by activation/deactivation of the alternator field (which should be on when I turn-on the ALT switch) ?

[Jamie]

The light will not turn off until you fire up the engine and the alternator is producing power. When my master is on and the alt field is off the dummy light is on but it will get brighter when the alt field is turned on. It was very cool during my first engine start to watch that lamp finally turn off.

[avee8tor13]

I started mine for the first time and forgot to turn on the field switch. Light went out after turning on the alt field. Boy was I a little nervous. I mounted my red light right above the ign switch so I would always see it if it came on.

Best of luck.

[rvmills]

Phil, concur with the others, It'll go out when the ALT sends you some juice!

Please excuse a little related thread drift. I have a question for a similar DIY set up that I have. I have an ALT OFF annunciator that currently comes on if the ALT switch is off. As currently installed, it's a "dummy, turn on your ALT" lite. Somewhat less useful than my original intent, since I turn the ALT on before start, and leave it on until after shutdown (and I have a Dynon EFIS and an ATD-300 that both warn of low volts).

My original intent was to have it be both a switch position "hey dummy" lite (on if ALT sw is bumped off), and a low voltage lite (on if alternator output drops below a predetermined value). The dual mode was deferred when the panel project ran into time delays, the wiring guy that was helping me ran short on time, I just wanted to get 'er done, and I had those other warnings!

Still wouldn't mind trying to wire that feature back in, so any e-gurus know of a straight forward way to wire in that feature (somehow sense the ALT output and turn on the light when below X volts...and open to suggestions on what X should equal).

Thanks much, and thanks Phil!

Cheers,
Bob

[IowaRV9Dreamer]

You might check out perihelion design. I saw they have a LED light with a built-in voltage sensor. I think it comes on at 13V.