Vertical Power and strobe light issue

Just a quick note as I try to organize a procedure for diagnosing why my strobe lights have started working only periodically.

I don't do a lot of night flying, although I always use strobes, and I first noted the problem when we picked up the plane in Hibbing at night a couple of weeks ago to fly it back to South St. Paul. But, because I fly mostly during the day in the summer and that was my first night flight since.... geez, I don't know when... it's possible this has been a problem for a while. Anyway, at startup the strobes wouldn't fire although after awhile they came alive.

Sometimes they work. Sometimes they don't.

So I figure the problem is one of these.

a) The VP-50 switch itself. I figure this is easily diagnosed by reassigning that circuit to another switch and see if it works.
b) A loose or broken wire or ground at the power supply (or maybe at the VP-50 but not likely considering how many there are all bundled together. It's like freakin' ree-bar.
c) A bad power supply

So here's the Vertical Power VP-50 (may it rest in peace) question for those of you familiar with its operation .

Since the VP-50 is supposed to warn of a fault in the circuit and the annunciator is not illuminating, what is it NOT?

The vast majority of electrical problems are due to bad connections. Of your 3 choices, I vote for b).
By "fault", do you mean shorted circuit AND open circuit, or just shorted circuit?

The VP-50 shows a short circuit or an over current. It doesn't show an under current, which some of the other VP models do/did. I would also vote for B. Make sure you have a good connection of power to the power supply.

Also, do you have a single power supply for all strobes, or a separate power supply for each? If the former, then I would check for any corrosion on the connections at the power supply or possibly any loose connections. If the latter, then are none of the strobes working (more likely a power feed problem) or just one of them?

At any time you can pull up the Strobe circuit on the VP-50 and see how much power it's drawing. A 3-strobe Whelen system will draw about 6-7Amps.

Timely

This is kind of timely. I am tracking down an issue with my strobes but I got two out of three working and I have a single power supply. I tried swapping the wings strobes at the power supply and one line is definitely not reacting. I think my issue is a bad strobe bulb or a wiring issue. I'll find out which this weekend when I can get back to the airport.

I have just a single power supply (Whelen comet flash). I suspect it's the wires into the supply. It's mounted on the side of the fuse so perhaps gravity has not been kind.

it would be cool if the VP-50 had been designed to say "hey,you turned something on and it's not drawing any juice".

Mike if you have the same system and NONE of the strobes are firing, it's not the bulbs. The Whelen system will fire either the tail or the wing (or one of the wings) in the absence of current to any of the three locations. It will alert you -- and I don't know if this is intentional or not -- to the absence of one of those by firing faster (kind of like your car turn signals)

Bob,

I had the very same problem a year ago with my -7. I too have a Whelen system with a single power supply. The issue was the power wire going into the Molex connector at the power supply. It was blackened and obviously not carrying power. Not sure how it happened but a new connector and a little creative splicing and all has been well.

Thanks Doug. I'm 99% sure that's where the point of failure is. It's just such a pain in the neck getting back there that I wanted to make sure that was a reasonable place to start.

Nova?

Bob,

I believe my power supply might be a Nova. I got it when I purchased the kit off another builder and it has a CreativAir sticker on it. The strobe tubes are Nova Hide-A-Flash's. Like I said earlier the tail and left wing are flashing. The right wing is not. Mine is not a vibration issue because it hasn't flown yet. I bought a couple of tubes for spares so I will try a new tube first before I start back through the wiring. Its my last light issue before I call in a DAR for the final inspection.

Bob it is good to see you out and about with the plane after all your struggles with trying to build it.

LettersFromFlyoverCountry said:

it would be cool if the VP-50 had been designed to say "hey,you turned something on and it's not drawing any juice".

Click to expand...

That would be called a VP/X or VP-200! I just had to rub a little salt into the wound.

That's one of the best features of the VP/X that I've had to use more than once in troubleshooting.

Fearless said:

Bob,

I believe my power supply might be a Nova. I got it when I purchased the kit off another builder and it has a CreativAir sticker on it. The strobe tubes are Nova Hide-A-Flash's. Like I said earlier the tail and left wing are flashing. The right wing is not. Mine is not a vibration issue because it hasn't flown yet. I bought a couple of tubes for spares so I will try a new tube first before I start back through the wiring. Its my last light issue before I call in a DAR for the final inspection.

Bob it is good to see you out and about with the plane after all your struggles with trying to build it.

Click to expand...

Ah, I missed the part about some of them flashing.

thanks for the note. I probably am about to get a 6-month "vacation" courtesy of the FAA, but at least it'll be over the winter when I don't fly much anyway thanks to the buildup of ice outside the hangar in the winter.

I'm getting too old for Minnesota.

Quick update: Like Doug Weiler, I found the male Molex pin was blackened so I replaced it and made a new ground wire and reinserted and tested.

And the strobe worked. Until it didn't.

Pushing back and forth on the new pin and wire, I found the strobes would alternatively work and then not work.

Turns out the problem was the female pin at the power supply had become just enlarged enough, I guess, that the electrons would jump across the connection until they couldn't.

A little small flathead screwdriver pressure to close up the female pin fixed the problem.

LettersFromFlyoverCountry said:

it would be cool if the VP-50 had been designed to say "hey,you turned something on and it's not drawing any juice".

Click to expand...

Bob,

That feature IS in the VP-50 - it is called current fault alert. You have to enable it for each circuit which you can do in setup.

Also, you can read the current of each circuit, and that is accessible any time form the main screen (it is not in setup).

Those two things should help you troubleshoot the problem. VP-50 manuals are still up on the web site.

Found It

My problem turned out to be a bad crimp connection at the wingtip. I cut off all the strobe connectors at the right wing tip and re-did them and all is well now.