Strobe lights again

[Dooley]

I just replaced my Whelen 3 light strobe power supply HDA-CF. The Wingtip strobes work fine. The belly has a new flash tube A469A and is intermittent at best. When it should be firing I can hear a faint clicking like its arcing to ground. In fact I have seen it arcing to ground from the plastic base of the strobe tube. I thought the flash tube was defective and Spruce sent me a replacement, very same symptoms. the Belly flashes (42joules)with twice the power of the wing tips (21joules) so I can see there is a fair amount of power to be contained in that belly strobe. It is very difficult to unground this fixture. If you let the flash tube hang below the airplane in free air it flashes perfectly every time but I don't think it would last very long like that. Three conversations with Whelen tech support has not provided a solution. I think whoever is molding the plastic bases has affected the chemistry somehow and has made them to conductive. Neither flash tube has shown any sign of damage. It's a 50 percent chance it will work anytime its mounted properly. This shouldn't be this hard.

[170C]

Dooley, some of our electronics members should be able to offer you a solution. Be sure to let us know how you solve this issue. I have a belly Whelen strobe on my plane, but I don't recall offhand what model it is. I have one power supply for all three strobes, but have the wings set up to flash at slightly different times, thus each is brighter than if both wing tips flash at the same time. The only issue I have had with the belly strobe was after washing the plane ( I assume that was the culprit or maybe the plane was out when it rained) water got into the lens and shorted the unit out. When I replaced it with an identical unit, I drilled a hole in the lens so any water that might get in there would have a means of draining out. That happened many years ago and so far no problem with water in the unit.

Frank

[Dooley]

Thanks Frank, good to hear from you. I hope Tennessee is doing you right. I suspect the solution will be simple when we see it. My brother gave me some thick electricians tape that I put around the base of the Flash tube Assy. and that seemed to work but now it's not. Still open to suggestions and it seems I'm the only one with this problem.

[Dooley]

Think I got it. Bad ground at the power supply. Those little amp connecter plugs where the power comes in from the switch is the number 1 pin the number 2 pin is the ground. Corrosion on that pin was not cleaned when the power supply was replaced. The wing tips with less energy and further proximity to a ground worked through the corroded pin but the higher energy and closer proximity on the belly strobe found an alternate path. So many weird electrical problems are bad grounds, should have looked there first. Anyway I'm not putting that back seat in again until It's a certain fix. Some things don't care how they are grounded but strobes must ground thru the power supply. Dooley