Generators: Rated as 'clean power'. How can I tell and is there something to clean it

[Dadnatron]

I have an HF 8750/7000W gas generator that does a great job.

But in looking at welders, I've seen then state the generator must be rated as 'clean power'. I somewhat understand what they are saying, however, I don't know (doubt) that mine is rated as such. Is there something I can 'add/interpose' between the generator and the welder to clean up the power and make it safe for a welder?

I'm looking at Everlast 211si and 251si. This is in their 'notes' section:

NOTE: Use only with a generator rated by its manufacturer as "clean power" if using with a generator. Consult manufacturer of generator for certification. Everlast does not approve or endorse generator brands or models, however, if the damage to the welder occuring from use with a generator not labeled as producing clean power by its manufacturer is not warrantable. Typically clean power is represented as less than 5% THD.

 

[Jeepnford]

To really clean it up you would have to run it to batteries then invert it back to AC. A very expensive proposition with the power draw of a welder. It would be a very large UPS. I don't know a cost effective way to do it.

 

[Birdhunter1]

There are some generators that are rated as clean power but they are usually more costly.
Most Generac models from what I have understood are clean, I know Mark with Everlast had posted this one on weldingweb 181 i NOT GENERATOR COMPATABLE

http://www.northerntool.com/shop/tools/product_200664810_200664810

http://www.northerntool.com/shop/tools/product_200664808_200664808

 

[sw99]

I run my Hobart 210MVP and DR Tig 200D off my HF Predator 6500/5500 all the time and no problems yet.

 

[Tractor Seabee]

I have operated welders of several types on generators of several types. It was not a problem. These were not the modern solid state weldesr though. Pretty hard to screw up a transformer/rectifier unit or a motor driven welder. Some jobs I have been on generators were the only power when we started work. I have even operated computers and other electronics on old generators with no problems. The "clean power" thing may be a manufacturer CYA tactic in case some one uses a poorly functioning generator. As contractors we ignored a lot of that ballyhoo and either it was not a fact or we got lucky, but that is how contractors operate; one more risk.

Ron

 

[Cord]

Although on the verge of becoming obsolete, the older transformer welders are capable of running on dirty power. As electronics become more prevalent the need for a clean power source will become more prevalent. Generally inverter generators produce "clean" power and inverter welders can run on "dirty" power. The key factor is that there is a transformer or inverter between the two to help "clean" the power. In the case of your lap top, you got lucky because the power supply had a transformer in it. My Makita battery chargers do not have a transformer and they'll blow instantly when receiving dirty power.

 

[vsteel]

If a generator doesn't say it has clean power or THD <5% it doesn't. Clean power is something generator manufacturer will brag about. Cheap generators almost always don't have it. Yes you can clean it up but really your best bet is get a generator that does have clean power because it is going to be simpler and cheaper or as stated get a transformer machine.

 

[johncanfield]

The inverter type welders are more sensitive to 'dirty' power so the advice goes. I suspect a major issue is the instability of the frequency on a governor controlled generator and when a load is removed (you stop the arc), the voltage will spike. This spike can be the kiss of death for the welder electronics depending on the engineering quality of the welder design.

 

[Mark @ Everlast]

Harbor Freight has come out with one that they compare to a Honda. I would think that it is clean power. Cheap price too. The predators seem to be holding up well.

 

[vsteel]

For those that want a bit of an explanation of THD, here is something I wrote a while back.

http://www.tractorbynet.com/forums/attachments/142090-15kw-pto-generator-harbor-freight-post4458464.html#post4458464