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maus92

Well Known Member
OK, I've been doing a series of ground checks this past week on my RV-8 rebuild. I've migrated from flying a rented C-172x which has a split master and keyed ignition, to my own aircraft with separate magneto and ALT switches, and a starter button. Works well, but I have found / caught myself forgetting to switch on the right mag after start, and/or the ALT switch. I haven't developed a checklist yet - and that will help - but I'm wondering if I need to do some more engineering to add annunciators that will cue me when I'm doing something stupid. The VP-X will eventually indicate an alternator problem when buss voltage drops too low, but that seems to be a bit delayed to me (BTW, I have a Plane Power 60amp alt.) And nothing except for possible engine roughness would manifest a forgotten mag enabling.

My question is has anyone had the same issues, and done anything to mitigate the situation? Does the Plane Power "Alternator out" line illuminate an indicator light (if installed) if the alternator field switch is not turned on? Could/should a lamp be wired to illuminate when a mag switch is grounding? Is this a non-issue solved by checklist?

CA
 
The alternator out connection can drive a lamp up to 100ma, this works fine when you have forgotten to turn on the alt field. See the manual there is a small wiring diagram: http://planepower.com/pdf/AL12-EI60_B.pdf
I have a self built warning panel and the g3x warns me if i have a low voltage condition.
A checklist would help and I recommend use one. I use it on every flight.
Btw, I use a split master and keyed ignition, exactly like in the 172, it's just simple.
 
maus92 said:
Does the Plane Power "Alternator out" line illuminate an indicator light (if installed) if the alternator field switch is not turned on? Could/should a lamp be wired to illuminate when a mag switch is grounding? Is this a non-issue solved by checklist?

CA
Click to expand...

Yes
I have an LED for ALT OUT and it works as it should.
 
If you do a mag check prior to every flight you should catch the neglected mag switch then. You're not going to hurt anything taxiing on one mag.
 
flyinga said:
If you do a mag check prior to every flight you should catch the neglected mag switch then. You're not going to hurt anything taxiing on one mag.
Click to expand...

Good call - haven't gotten to the test flight yet, so I expect I'd find the mag switch issue during run-up.
 
kai said:
The alternator out connection can drive a lamp up to 100ma, this works fine when you have forgotten to turn on the alt field. See the manual there is a small wiring diagram: http://planepower.com/pdf/AL12-EI60_B.pdf
I have a self built warning panel and the g3x warns me if i have a low voltage condition.
A checklist would help and I recommend use one. I use it on every flight.
Btw, I use a split master and keyed ignition, exactly like in the 172, it's just simple.
Click to expand...

Thank you - have you considered wiring the alternator indicator line to the G3X as a discrete input? I'm thinking that may be a way for me to proceed, since I also have the G3X system.
 
I recommend aural warnings for OP and low voltage over lights which sometimes don't get you attention in bright sunlight. Ask me how I know...
 
mag switches

I had one with switches for the mags, and I too always forgot to turn on the right mag after start-up (even with it running rough the whole time!). I would catch it after 30 seconds or so and turn it on.

It never failed that when I would do my mag checks prior to take off, the "off" mag never passed the run-up tolerances, and I would have to clean things up with the leaned out/high rpm operation.

I gave up and went back to what I learned on: split switch and keyed ignition.
 
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1. Write and use a checklist
2. Set VPX to alarm when buss voltage is below 13 volts. That way you get an immediate alarm on alternator failure.
3. Use a checklist every time.
 
Get a VP-200 :D

The mag switch position is configurable for each mode of flight and the system annunciates if the mag switch is in the wrong position; no Alt switch is required.
 
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