theory help

[bark]

Good afternoon,

I was wondering if you could help me here on a puzzling theory question? My son's company, not electrical, dirt contractor has a portable light standard that runs off a generator. There are 4-1000 watt metal halide lamps. Each has it's own ballast and capacitor. He asked me this morning if I could take a look at it because of a problem they were having. It has four separate switches that turn on the lights individually. Now the question. I would turn # 1 switch on and fine, it worked, turned #2 switch on and fine, it worked, then turned # 3 switch and it worked, then I turned # 4 switch on and that in turn turned off # 2 and #4 would not work. The same happened if I turned #4 on and then turned #2 on, both light would not work. I did find a that the cable leading from the switches was pinched at the knuckle where the light stand could be cranked upright. There were 4 smashed wires along with the neutral wire that was also damaged. There was also a grounding conductor in the cable but didn't notice any damage. I've been trying to think of the theory that involves this but can't seem to come up with an answer. There were no tripped breakers/switches. Thanks if you can help my curiosity.

P.S. I have been a journeyman wireman for 35 plus years with a masters license so hope you understand why this puzzles me.

 

[just the cowboy]

high resistance connection

high resistance connection

I would think that the same hot wire (pigtail) feeds sw 2 + 4 and has a loose connection. It can't handle the current of two loads and is breaking down when all 20 amps is called for.

 

[bark]

Therory help

Therory help

I would think that the same hot wire (pigtail) feeds sw 2 + 4 and has a loose connection. It can't handle the current of two loads and is breaking down when all 20 amps is called for.

No, no loose connections, I checked. When I removed the pinch cable and separated the wires it worked fine. No pigtails, each light has its own switch and capacitor and ballast

 

[Smart $]

No, no loose connections, I checked. When I removed the pinch cable and separated the wires it worked fine. No pigtails, each light has its own switch and capacitor and ballast

You do realize electricity is categorized as a phenomenon. :happyyes:

While we understand much of it, every once and awhile it throws even the very knowledgeable for a loop. While I admire your curiosity, this is one of those scenarios I'd chalk up to inexplicable and move on as long as it's fixed and everything's working normally!!!

 

[growler]

I would turn # 1 switch on and fine, it worked, turned #2 switch on and fine, it worked, then turned # 3 switch and it worked, then I turned # 4 switch on and that in turn turned off # 2 and #4 would not work. The same happened if I turned #4 on and then turned #2 on, both light would not work. I did find a that the cable leading from the switches was pinched at the knuckle where the light stand could be cranked upright. There were 4 smashed wires along with the neutral wire that was also damaged.

When I removed the pinch cable and separated the wires it worked fine. No pigtails, each light has its own switch and capacitor and ballast

I think that when you turned on the #4 switch that you shorted the circuit to the frame. It may not be grounded well enough to cause a dead short to ground and trip a breaker but would cause a reduced voltage at the balast.

When you seperated and insulated these conductor from contact with the frame then everything worked.

 

[GoldDigger]

A good conjecture.
Also there is the possibility of a compromised neutral and balanced/unbalanced loading on two sides of an MWBC. That sounds shaky though, and I cannot see exactly those symptoms.

 

[growler]

Also there is the possibility of a compromised neutral and balanced/unbalanced loading on two sides of an MWBC.

When you smash up a bunch of wires you really never know what you are going to do. The only thing you can count on is "Sod's Law".