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solbigjeep
04-09-2007, 10:43 PM
are all wire feeders[not a welder just a feeder]voltage sensing?also how can you tell one from the other? and is there a way to convert a nonsensing feeder to a voltage sensing feeder if needed?

David R
04-10-2007, 06:27 AM
Some feeders like the hobart and Lincoln are "across the arc" this means the power to drive the motor comes from your welding power. These feeders have an extra lead you hook to your ground. This is not a voltage sensing lead. Other feeders hoook directly to the power source by a seperat cable. Some also have a lead that hooks to your work. This is a voltage sensing lead.

I doubt you could change either one.

David

weldersales
04-10-2007, 09:34 AM
Almost all manufacturers build an 'arc voltage feeder'. In the case of Lincoln, LN25, and LN22 series - Miller S32 series or Suitcase 12VS series - Hobart uses term 'Hefty'. These use the welding voltage to run the motor. This is not an afterthought - it is by this technique that you are able to weld with a wire process using a stick source. Normal, conventional, feeders run constant speed and need a constant voltage power source. Normally, they run on 120, 24, or 42 volts ac. That voltage sensing lead you are thinking of, for these feeders, is simply a way to read voltage directly at the arc. weldersales

solbigjeep
04-10-2007, 08:49 PM
the feeder i have is an old snap-on model FW 111.it has leads for the motor and the power to hook to the welding machine.the feeder control box says fw111 and has wire speed adjustment knob.last owner said he used it with a syncrowave 250[cc not cv]so wanted to make sure he wasn't b.s.ing me as i don't want to fry the thing.i've used mig welders and tig but never a stand alone feeder like this,not sure if this thing is worth the trouble.p.s. this thing looks pretty old.

weldersales
04-11-2007, 11:24 AM
If you can, PM us a picture. Sounds like a Systematics feeder. If so, it probably is a standard constant speed 120 vac unit. Assuming that and he was using it on a Syncrowave 250, you are in a position to damage the feeder, and secondly, you will not like the welding result. The problem is you are trying to run a wire process with a stick power source. The arc will tend to walk up the wire and there is nothing to keep that from happening since the feeder is constant speed. The arc voltage feeder will see this, immediately speed up the wire in response to rising voltage, keeping arc going. That's why you pay the big bucks for arc voltage feeder. Second problem occurs when someone leaves the hi freq on. There goes the solid state devices in feeder. If you want to verify feeder is a Systematics, look behind front panel and you will see a black box with all components inside and bolted to panel with shaft for speed knob going thru. A plug in relay is on the box, I believe. weldersales

solbigjeep
04-11-2007, 07:56 PM
yeah just dug it out of the garage.its a systematics feeder,says so under a cover i didn't notice before.i'll try for some pics soon.thanx for the help with the i.d. one more question;what's this thing worth,i see fairly new miller suitcase welders for like 500 dollars on ebay all the time.may as well sell this thing cuz i'm not gonna buy a big welder to run it.