AC Tig / Lights Flicker

[Chopper]

Tig Welding some 1/16" Aluminum AC Hi Freq / last night and my Wife came out to the shop and said the lights in the house were flickering.

Some details:

Shop detached from house on a non service rated panel.

Welder ground connected directly to work being welded

Non service rated panel in shop has a ground rod outside shop and by local code also has a equipment ground coming from main service panel in house.

Welder wired with two hots and a equipment ground.

lights in shop don't flicker.

T.V. set in house is fine no surging or flickering

Any insight would be great.

[Hobart Expert Rock]

HEY CHOPPER...........HF IS A RADIO FREQUENCY......... WOULD THESE BE FLORESCENT LIGHTS OR LIGHT BULBS.......... ALSO GROUND TO HOUSE AND GROUND TO SHOP ARE THE SAME 8' GROUND ROD...........THIS MAY HELP..........HF RADIATES 50' IN ALL DIRECTIONS............. WILL ATTACH ITSELF TO THE PHONE LINES, LIGHT'S, WILL CAUSE OVERHEAD CRANES TO MOVE WITH OUT OPERATOR, ETC..........HF IS SNEAKING BACK IN THRU THE 2 GROUNDS ON THE SAME 8' GROUND........... RUN ANOTHER ONE CLOSE TO THE HF MACHINE.....................8' GROUND FOR WELDER WILL MORE THAN LIKELY TAKE CARE OF THE PROBLEM.............BE SAFE.......ROCK.....................
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[Chopper]

Hi Rock,
Standard non flourecent. The main service panel (house) and non service rated panel (shop) are each on their own ground rod but by code there is a equipment ground that comes from the main service to the non service rated panel. These ground rods are about 70 feet from each other. The welder has less than a two foot run form the non service rated panel in the shop.

[Franz]

Chopper, what type of soil are you on, and what is the soil moisture situation?
Since you don't mention, how old is the electrical installation?
Is the wire feeding the shop panel from the house panel aluminum or copper?
Are there aluminum to copper connections in the circuit between the house and shop?

[Roger]

Light flickering is probably caused by loose connection at main circuit breaker panel on side of house that sub feeds your shop.
Have some one listen for crackeling noise as lights dim at the main circuit panel at house. Then thighten the loose connection if copper.

Also check for voltage drop while under load at house and shop.

[Hobart Expert Rock]

HEY CHOPPER..........WHERE WE AT WITH YOUR LIGHTS.........WE KNOW WE HAVE A PROBLEM SO LET'S NOT CREATE MORE PROBLEMS..........BE SAFE..............SHALL WE GET SOMEONE IN TO LOOK THE BOXES OVER.....................YOUR CALL...........ROCK
[email protected]

[Chopper]

Franz
My yard has a steep grade so the are never stays to wet but we have had rain all spring. The electrical installation is only two months old. All copper, #2 wire, no Aluminum connections at all. Is it possible that the welder is creating a voltage drop and causing the lights to dim or is it also possible that the HF is causing the normal 60 hrtz of the lghts to be affected.

[Franz]

Since you're on fairly wet soil, and have a relatively new install, the probability of a corrosion problem is low.
Like Rock said, HF can do some strange things, especially when it comes to radio controlled cranes.
Since you are only seeing the problem with incandescent lights, the problem is even more of an oddball. Voltage drop is certainly a possibility, and could easily be eliminated or confirmed with a voltmeter. The likelyhood of voltage drop though wouldn't be my first consideration, unless the problem only manifests itself when you are cranking the welder near max output.
The difficulty here is you yourself aren't seeing the symptoms, but getting reports from your wife. Can you convince the wife to run the welder, at the same output you were, while you look for symptoms?
If you can, you're a better man than I am.
You need to determine if the problem is relative to HF or just high power consumption.
After checking the voltage under load, I'd look for a bad connection, probably at one of the breakers serving the welder.
It's not uncommon for breakers to fatigue wherre they contact the bus bars either, especially breakers that are subjected to intermittant loads like a welder.
The hard part here is that you need to find the problem while the welder is in operation.

[cope]

Another possiblity is a loose wire somewhere. I had similar problems in the past and found a couple of loose neutrals in the breaker box.

[Chopper]

Thanks Guys. I appreciate all the response. I am going to have my Dad come over and check things out while I weld. We'll see what happens

[INTP]

Are you sure the lights don't flicker in the shop? Hard to tell while welding, and it seems like a really odd scenario.

My in-laws had a flickering problem that I tried to help them track down. We went through the main panel and also inspected many of the recepacle and switch boxes. They got the electric utility company to come out, and they found that the lugs on the utility side of the meter were loose. No problems since (and they're really lucky they didn't have a fire!).

This is worth tracking down.

[vwguy3]

Maybe not directly related BUT I had a problem with the lights in the house getting brighter with a load on the service,like the pump turning on or the washer running. Nobody could answer the question I called the power supplier and they had meters installed to monitor the problem, they said nothing was wrong. Finally they replaced the transformer in my yard and Bingo the trouble went away.By the way my shop is on a seperate meter off the same transformer and I never noticed that problem in the shop. The things that make you go Hmmmmm.

[Franz]

It wouldn't be the first time the Utility denied the problem could exist till somebody from the outside proved it was the utility's problem. That's why manufacturers like Dranitz and Amprobe make equipment.
My utility, once a proud independant, is now a baby Enron, less than 40 line crews when we had over 150 back in 90. After our last ice storm they asked for a rate increase to cover restoration cost because they had completely ignored maintainence for 10 years. I am waiting for the Public Service hearing, gonna have me some fun. I sure ain't gonna get another complementary hard hat as a thankyou this time.

[uhmgawa]

Originally posted by vwguy3
..I had a problem with the lights in the house getting brighter with a load on the service,like the pump turning on or the washer running. Nobody could answer the question

That is caused by a large load between one service
hot and neutral, and a smaller (eg: lighting) load
between the other hot and neutral. The surge is
due to a voltage drop in the transformer and/or
service feed causing the voltage potential of the
neutral to be skewed to the hot under heavy load.
The potential between neutral and lightly loaded
hot increases by the same voltage and causes the
intensity surge in your lighting.