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oldstarfire
02-08-2017, 10:29 PM
Anyone encountered this?
I put an LED bulb in a move-able light over my shop vise.
I went to MIG weld a small item, and expected my self darkening hood to go dark as it always did with the previous incandescent bulb.
B'Gosh, it didn't go dark till I hit the arc!!
Anyone else have this effect?

Evan
02-08-2017, 10:40 PM
Yes. My former shop was all LED lighting for many years. I always had problems with the auto darkening on two helmets so I did as much welding as possible outside the front doors.

JoeLee
02-08-2017, 11:38 PM
Anyone encountered this?
I put an LED bulb in a move-able light over my shop vise.
I went to MIG weld a small item, and expected my self darkening hood to go dark as it always did with the previous incandescent bulb.
B'Gosh, it didn't go dark till I hit the arc!!
Anyone else have this effect?Well it sounds like it's working as it should, darkens when you strike the arc. Were you expecting something else ??

JL...............

J Tiers
02-08-2017, 11:43 PM
The LED lights have light in peaks at certain wavelengths/colors, and not elsewhere. The incandescent has a pretty continuous spectrum. Possibly the incandescent had some energy up where the auto-dark is sensitive, and the LED does not.

What's the odds so long as it works when it should.

Willy
02-08-2017, 11:54 PM
Yes, sounds like a good thing to me. It's a nuisance when artificial lighting sets off the auto-darkening feature when it's not wanted. I hate having to turn lights down so as not to trip the helmet prematurely, as this somewhat defeats the benefits of the auto-darkening helmet.

ahidley
02-09-2017, 02:47 AM
My guess is that the leds are directional and your not looking at them. Try holdng the helmet right in front of a led bulb, not to the side.

Evan
02-09-2017, 03:17 AM
It isn't something to worry about. The helmet filter takes out the UV, dark or not. The darkening is for lowering the brightness only.

Jaakko Fagerlund
02-09-2017, 05:00 AM
I too don't see the issue from the described, as auto-darkening helmets idea is to darken once you strike an arc.

macona
02-09-2017, 05:59 AM
Older helmets actually looked for the 120hz flicker from the arc among other things. Thats why they didn't work so hot with inverter machines. Better LED lamps will be driven from a buck/boost converter which will have a higher switching freq than the cheap LED lamps that just put a whole bunch of LEDs in series and run them off of line voltage.

dave_r
02-09-2017, 03:40 PM
I too don't see the issue from the described, as auto-darkening helmets idea is to darken once you strike an arc.

Well, it's nice to be able to see the parts and the end of the gun so you can position it properly prior to striking the arc.

oldstarfire
02-10-2017, 12:57 AM
NO, this is NOT a problem, this an ADVANTAGE to me.

I love not loosing the view before striking the arc.
Thought it might be a help to others.

Sorry to be a pest...................
Wont do that again!

Jaakko Fagerlund
02-10-2017, 04:21 AM
Well, it's nice to be able to see the parts and the end of the gun so you can position it properly prior to striking the arc.
The OP described the full opposite of that, which is just the way the helmets are designed to work for just the reason you say, to ease positioning and pointing the welder.

Jaakko Fagerlund
02-10-2017, 04:22 AM
NO, this is NOT a problem, this an ADVANTAGE to me.

I love not loosing the view before striking the arc.
Thought it might be a help to others.

Sorry to be a pest...................
Wont do that again!
Sorry if it all came out to you that way, it's just that words on a screen do not convey your intentions as well as spoken words do, so to me your opening post looked like a problem description and not a success story. My apologies.

vpt
02-10-2017, 09:18 AM
My fixed shade stays dark all the time. I think it is broken. Maybe I should try these led bulbs int he shop.

Willy
02-10-2017, 10:12 AM
My fixed shade stays dark all the time. I think it is broken. Maybe I should try these led bulbs int he shop.


Or flip the power switch on the welder.:)

vpt
02-10-2017, 10:36 AM
Or flip the power switch on the welder.:)

Sparks fly when I turn on the welder, I think there is something wrong with that too.