LN-7 feeder to CC power source

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Can a LN-7 feeder be used with a constant current only power source (idealarc R3R-400)? If so, what is to be expected regarding weld quality? The manual recommends a CV power source.
Reply:Iseem to remember all those power supplys as constant  voltage machines ,not constant current . some may have had switches to choose  constant  or variable voltage. if you want to squirt weld that combo ought to work good .  (by the way, linde inverted the Union melt (sub arc - squirt weld; Heli-arc, (tig) & mig , I am told.  Too bad linde let other companies take them over (the processes ) .Last edited by Roy Hodges; 01-15-2008 at 10:31 PM.[SIZE="5"Yardbird"
Reply:I'm with Roy Hodges on the old gray R3Rs, especially the ones with a triangle connector for changing voltage they were CV only.  However... I've seen the  newer red and black machines that are CC only.There have been posts discussing the use of CC machines,  with constant speed feeders. Anybody recall?
Reply:If I remember correctly, the R3S was CV only and had the triangular plate that was used to select the range.I think the R3R was CC only.The newer DC-400s and DC-600s had a switch and could be used in either mode.
Reply:BobC is correct, the R3S is selectable, and I do know that the R3R is CC only. But does anyone know if the LN-7 can be used with a CC power source or are they not compatible?
Reply:Correction to my #2   . Linde did not "invert" THE PROCESSES , lINDE                         i n v e n t e d THEM . .... SORRY[SIZE="5"Yardbird"
Reply:div5fab - Read weldgaults post #2 here:http://www.weldingweb.com/vbb/showthread...898#post142898Roy Hodges - I've noticed that just about all the big names seem to take credit for some level of developing most processes, even if it's just a carefully worded statement about their added refinements.Remember; Success has a hundred fathers,  failure is an orphan!
Reply:All the R3S's were CV and the 400 and 600 series had the metal triangle for selecting voltage that has been mentioned. All the R3R's were CC machines.           As for running a constant speed feeder - like the LN7 series - on a CC - stick - machine, you will not like the result. The arc will attempt to walk up the wire and burn into the tip. A miserable welding experience. You can run wire on a stick machine if you will get a feeder that is designed with a very fast response motor that speeds up wire speed whenever voltage rises, making it possible to maintain an arc. That is why people like Miller and Lincoln spent so much money developing the 'arc voltage feeder' like the S32 series and the LN25 series. They work quite well.     In the early days, manufacturers simply ran the feed motor off the arc. These machines are still widely used today as in the S42 Miller series and many of the smaller spoolguns. weldersales