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Electric help please

Its best to contact the welder manufacturer (if they are still around). The y've dealt with this issue in his area before. The local power company mig ht be giving you the more expensive route. Its in the welding manufacturer to give you the cheapest option (for service and other needed devices).

If that manufacturer is no longer around, contact a similar manufacturer of modern welders. Pretend like you are going to buy a new welder from them u sing the specs that you actually are on now. They'll probably tell you what additional devices you should install (any 60 amp breakers, xfmrs, sub-pan els, converters, inverters, freq drives, etc...) in preparation for your pu rchase of one of their welder set-ups.

The welding manufacturer might give you the lowest cost for other needed de vices/service not made by their welding manufacturing. They might even help to organize.

Reply to
mogulah
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On Thursday, October 30, 2014 1:05:18 PM UTC-4, snipped-for-privacy@whidbey.com wrote: Puget Sound Energy (PSE) has had complaints

It sounds as if the problem is the voltage sagging. You need to see the gr aph. If the problem is that the voltage drops while he is welding, then a rotary converter will not help. A inverter welder will be more efficient a nd maybe would not cause the problem.

Dan

Reply to
dcaster

A dedicated transformer for a business location with large instantaneous loads is the right thing to do. If the friend's business is home based (sounds like it) he should just pay a reasonable amount to fix the issue before the neighbor's complaints go to the city and then zoning issues might come into play.

Reply to
Pete C.

There's a lot of missing info here. First place I'd go is the engineering department of the power company. Took me several tries to get an operator willing to connect me to engineering, but once I got there, they were extremely cooperative.

My initial position would be,"I have x-AMP service. I'm using less than that. It's the power company's responsibility to supply me what I'm paying for."

Anything that generates heat depends on POWER/WATTS supplied. Drops in the power line voltage depend on AMPS delivered. For a device with lousy power factor, like a welder, you may need way more AMPS than you'd expect for that level of POWER/WATTS. Some simple power factor correction may help that. Stick a storage oscilloscope and current probe on it.

Transients are a different issue. I built a small spot welder from a microwave oven transformer. There's considerable hysteresis in the core as you move up and down the B-H curve. If I turned off the current at the peak positive current, then turned it back on at the peak negative voltage, I got a huge initial transformer current spike. It's also possible to run the B-H curve right off the end and saturate the core. Constraining the turn on to zero voltage crossing and the turn off at zero current crossing dramatically decreased that spike and increased welding repeatability.

Reply to
mike

Eric - I'm guessing you're associating "soft start" with motors and the long times inherent with heavy weight & limited horse power. I checked the inductance of a 10 amp 120 volt transformer & it showed .5 henry. The time for 240 volts & 46 amps comes to .095 seconds. (t = inductance * current / voltage). Keep in mind that I am guessing on this, but if you can find an addon "soft start" device with adjustable timing, it might be effective. I'd like to hear the result, too.

Hul

snipped-for-privacy@whidbey.com wrote:

Reply to
Hul Tytus

Greetings Hul, Soft start on a welder takes longer than for a motor. This is an adjustment on the welder itself. And even though it is pretty fast it is not ideal. Especially when welding aluminum because you want the metal to get hot as fast as possible. So the technique is to stomp on the pedal all the way to get the maximum current. Then as soon as a puddle starts to form the current is decreased. If the aluminum is heated slowly too much if the heat spreads into the surrounding metal. After several inches of welding in a localized area the work gets really hot until it is too hot to handle. Heating the metal fast, applying the filler fast, and getting off of the pedal makes for higher throughput. Today my friend is emailing me the graph from the power company so I will learn more and will post results here. I will also post the results of the final fix, whatever it is. Cheers, Eric

Reply to
etpm

In days gone by in line resistive units were inserted and when they heated up, a bi-metal by-pass switch shorted it out. Current flowing in the bi-metal (once tripped) kept it closed. Cut the current and the bi-metal cools and the process starts all over. The IR drop limits the current and also lowers the input voltage to the unit powering up.

Mart> Eric - I'm guessing you're associating "soft start" with motors and the

Reply to
Martin Eastburn

AFAIC, that device is called a breaker or a fuse and should be required in every form of circuitry over 5mA (milliamps). In a residential situation, if have you a 60 amp breaker, you can do a lot right from your own house without a short.

Reply to
mogulah

John - do you happen to know of a source for a time delay relay with a fixed 1 or 2 second delay? 50 amp capability with an economical price.

Hul

Ne> >Soft start on a welder takes longer than for a motor. This is an

Reply to
Hul Tytus

Hul, if he doesn't, try looking at

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. Massive selection and good pricing.

1-800-633-0405 Monday - Friday 9 a.m. - 6 p.m. ET excluding holidays
Reply to
Larry Jaques

Thanks - I'll take a look.

Hul

Larry Jaques wrote:

Reply to
Hul Tytus

And perhaps better to get a separate low-power delay relay and a contactor to handle the 50A load. Or perhaps a solid-state relay for the heavy load.

Good Luck, DoN.

Reply to
DoN. Nichols

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