dynasty fan question

[Hobbyist]

Is it ok to shut off my dynasty 200 before the cooling fan turns off? I've been waiting until it turns off before switching off the welder.

Also, anyone know what that causes the hissing type noise when the dynasty is idling? Is that just a normal inverter sound? I know it's not gas, because it makes the sound even with no gas.

[ASKANDY]

The hissing or slight buzzing is normal. It's the inverter engine changing the line power you are running. As for the fan, I'd let it run before cutting it off. The thermo switch is telling the micro to run the fans and I would like to see that finish it's cycle. If you are running it hard enough to turn the fans on, it would be a good idea to let them go.

good question.

A-

[Hobbyist]

All pretty much as I expected, but it's good to get confirmation.

[paulrbrown]

Askandy, I know you are the man, but when I was in the audiovisual world, the old practice of letting the fan run on a film/slide projector lamp to let it 'cool off' after shutting off the lamp was found to reduce lamp life by 50% or more. The action of forcing cold air onto hot parts which no longer needed the continuous air flow to remove heat while operating ,forced them to cool down too quick, kinda like quenching steel. Anyway, this procedure was in all of Kodak's manuals on the projection equipment they manufactured. Any imput form Miller's techs. BTW, I too, maybe out of fear of Baking something, let my machines run until the fan shuts off, except the Bobcat. Hope this sheds some light,pun intended, on the heating/cooling rate of electronics. PS, some recording studios leave all their computer,recording,sound equipment on all the time to keep any moisture form condensing and seem to have no problem,I used this practice with audio gear also, and have never blown anything, even after 15 years on the same amplifier. Best Regards, Paul Brown

[ASKANDY]

Paul,
Good point and that's why we let the micro-processor in the machine control heating and cooling. The thermo sensors placed in various places are not just on-off thermostats, they are thermistors that change resistance based on temperature. The micro board knows exactly what temp all the heat sinks are and regulates the cooling as needed. So if the fan is running, you can bet that it needs it and turning it off early and allowing the heat sinks to temp spike back up would be a bad thing.

Have fun!

Andy

ps.
I was one of Miller's techs for almost 6 years before moving into the training dept

[paulrbrown]

Thanks Andy, that was a great description, It does answer my question. And I thought you were just a 'Motorhead'. I worked 4 years at Volvo Trucks for their training dept., I was responsible for all the Audiovisuals and building simulators of their electronically controlled engines,brakes,airbags, the whole shootin match...That is the main reason I became so involved with TIG, and the Machine I personally bought [I was an outside contractor] Synchrowave 250, still have it,still love it, but the Dynasty 200DX is the newkid on the block, I still use the 250, so she won't become sad!!! Thanks again, Paul