Hello CMDWelding, the LN-25 will work with any CC or CV power source, a real quick run-down on the term CC, CC stands for Constant Current/ Variable Voltage, CV stands for Constant Voltage/ Variable Current. When you are working with a standard stickwelding machine you are actually operating on Constant Current/Variable Voltage, when you set the amperage to a given value it will maintain that value unless you change it, the voltage on the other hand will vary with the arc length, as you increase the arc length the voltage increases, as you decrease the arc length the voltage decreases. A Constant Voltage power source such as the ones used for most conventional wire welding will maintain the voltage that is set by the control unless you change it and the amperage will go up as you increase the wire speed or decrease as you slow the wire speed down. Something that may explain this a little bit better is that most suitcase welders such as the LN-25 are categorized as voltage sensing feeders, since a Constant Current/Variable Voltage power source will increase voltage as the arc length increases the feeder senses the voltage increase and speeds up the wire speed and if the feeder senses a voltage decrease it will slow the wire down. This is essentially how the feeder maintains a constant arc length even if the operator changes the wire stickout by moving the contact tip closer or farther away from the work. I'm not quite sure that I agree with your statement concerning D1.1 requiring CV. I don't believe that the code differentiates between CV and CC requirements as long as there is a qualified WPS to support the work being done. I am basing my statements on the fact that there are a lot of jobsites out there that are using Lincoln NR232 innershield wire and ESAB 8 innershield wire on LN-25 and SP32 feeders hooked up to Lincoln SAE 200's and Miller Big 40's and they are welding structural steel to the code standards of D1.1, all of these combinations are classified as CC power sources. Regards, aevald
The catch with D1.1 goes something like this.
CC power supplies are not compatable with *Pre Qualified* procedures.
D1 work done with CC power supplies must qualifiy the procedure using that equipment.
This includes by the way Pulsed Mig (GMAW-P); since pulsed GMAW power supplies rely on Constant Current to varying extents in the welding cycle. Some older pulsed units are full CC, while newer technology actually switches back and forth CC/CV many times per second.
Thanks Lawrence, I kinda thought that I hadn't quite totally gone nuts and the nice thing about the forum is that there are plenty of folks out there to explain stuff like this. Thanks again, aevald
Thanks Lawrence,
I forgot to say anything about the *Pre Qualified* statement. That is what makes forum great.
Gary
A lot of Lincoln SA-200's as well as their other engine driven generators are equipped with a Lincoln "wire feed module" which produces CV output, so until you look under the hood you can't really say.
JTMcC.
I am trying to set up LN-25's to run dual shield. I can get them running using CC off of miller 8 packs like mentioned by Gary. The interesting thing is today, we fried one of the machines in the 8 pack, so I borrowed a newer miller, (not sure of the model), set in a 4 pack, that was a machine that could run CC or CV. I set the machine on CV and could not believe what a difference it made. We had a nice crisp arc, a good wetting action of the puddle, smoother, flatter, just all around nicer welds.
I have a question though. The WPS's we are using, ( nothing I have any control over), are pre-qualified. I am going to bring this up to our QC man, but need to know what section of D1.1 to look in to find this. I guess more of what I am asking for, is chapter, number, in fact page, so when I go home sunday, i can pull out my book, look it up, and research this for myself before I bring it up to our QC man on monday. Quite simply, I am being lazy, but after working outside 10 hours a day, staying in a motel 2 hours from home, 5 days a week, outside in this cold damp wis weather, trying to get guys accustomed to our southern states, to produce decent, quality welds, I just want to relax sunday.
Whine whine whine, at least I am in wis so I have lots of cheese to go with the wine.
Thanks in advance.
Mike
Mike Here is a discussion where the chapter is quoted.
I don't have my desk copy here to double check but it outta bring you close.
http://aws.org/cgi-bin/mwf/topic_show.pl?id=7472#34894
I just looked closer at what I had typed and I want to appologize if I offended anyone from our southern states with my comment. (trying to get guys accustomed to our southern states, to produce decent, quality welds). These guys are producing sound welds, the comment was in reference to our weather up here. These poor guys are up here trying to help us build this boiler in very inclement weather at times. They are walking around so bundled up that they can hardly walk, yet they keep right on going. So please accept my very humble appology if anyone took the context of my poor choice of words to mean something that sounded very rash and arrogant.
Mike
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