110 DC to 110 AC ? ?

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Are there any inverters out there that can take 110 dc current and convert it to 110 ac ?  I know this question belongs in the electrical section but i am thinking of it as it relates to the SA 200 with dc auxillary current.  The only inverters I know of are the 12 v DC to 110 AC - which people use on the 200.  I haven't seen a simple box you could plug in and have instant AC on the other end.  I guess I was thinking "if they can put a man on the moon then why can't . . . "  Thanks, sorry if this question is trivial, always learn'n.
Reply:What exactly are you wanting to power?  Drills and grinders run fine off of the DC power and I'm assuming that was the original intent.My name's not Jim....
Reply:Originally Posted by Boostinjdm Drills and grinders run fine off of the DC power.
Reply:I believe that those 12v inverters convert the 12v dc to 110-120 dc and then convert to ac so I don't see why there wouldn't be a way to do it.If all else fails maybe put a bigger alternator on the engine and run an inverter off that? Just an idea.
Reply:just wondering if anyone has a inverter that can plug directly into a 110 DC outlet and then put out 110 AC.  I know I can run my dc grinders, porta band, etc. off the DC power but was thinking if I wanted to run sensitive electronics off it like a radio.  Also, If the welder had AC I could use it as household back up power.  I know the 12v DC inverters are the standard, but that requires hookup to welder battery which puts more stress on the battery and altenator.  A simpler system would seem to be plug an inverter directly into the 110 DC outlet on the control panel and get 110 AC at the inverter.  Thank you for the replies so far.
Reply:Originally Posted by feetfatsI believe that those 12v inverters convert the 12v dc to 110-120 dc and then convert to ac so I don't see why there wouldn't be a way to do it.
Reply:Sorry but I must recommend against this idea.First - the exciter is only rated at 1175watts max (?) and I can't say what the main generator is taking up of that.  Yes you can run a grinder but its not 100% of the time.  Trying to run a/c will also probably mean it'll be more continuous that normal grinder use.  You might exceed the duty cycle of the exciter.Second - is the expense you will incur if you do exceed the exciter's duty cycle. IMO a better idea is to just put on a larger alternator on the engine and invert that power, leaving the exciter alone.  Just don't tighten the fan belt up too tight our you'll trash your water pump bearing (been there - did that) With a dual belt main pulley you could mount and run a small 2kw ac generator off the engine's crankshaft, but I'd recommend an electrical inspection by a certified electrical inspector before putting that into operation.  If you did that you'd have quite a bit of ac available, without the inverter, or the massive 12v amp draw,  to mess with.Take care of your exciter.  Its at the heart of your welding machine and needs TLC.  (IMO).  Learn its duty cycle and stay within it with your draws.  Keep it in tip top shape and it'll keep you welding.  At least thats how I've come to learn it anyway. lolGood luck manLaterLast edited by slowhand; 01-04-2011 at 07:02 PM.
Reply:Yup, that 115VDC is only good for 10 or 15amps depending on the age of the unit.  Not a very good back-up power source for the house.MM200 w/Spoolmatic 1Syncrowave 180SDBobcat 225G Plus - LP/NGMUTT Suitcase WirefeederWC-1S/Spoolmatic 1HF-251D-1PakMaster 100XL '68 Red Face Code #6633 projectStar Jet 21-110Save Second Base!
Reply:Thanks for the backup duaneb55.We must remember that as long as the machine has a rheostat hooked up the main generator is also using some of the exciter's output even when we're not welding.  The fields are still loaded.  This is evident when we unhook the remote and see that spark and also when we flip the local/remote toggle (with the engine running) and burn the switch up.  How much current its using I've never metered.  It depends on where the rheostat is set.I've seen some old timers set the rheostat on 100 to help warm up the machine faster in the mornings especially when getting ready to test.  So the exciter works harder depending on where its set.  This will leave somewhat less current available.I think the way it is - the total output is at the duty cycle.  My 200d's exciter is rated 15amps at 35% duty cycle.  So if I'm pulling 15amps then I can only pull it for 3-1/2 minutes out of 10 then I must remove the load and let the exciter cool off the rest of the 10 (6-1/2 minutes).  Not knowing what the main generator is drawing makes this a different number.  There is a way of calculating what the draw can be for the duty cycle to be 100% but I can't remember it right now.  You take the amps and the published duty cycle and figure it that way. lolJust another thought.Good luckLast edited by slowhand; 01-05-2011 at 06:05 AM.
Reply:wow, never knew there was a duty cycle on the exciter.  Guess I am scrapping this idea. LOL !  Thanks slowhand and duane !
Reply:You know, about 30 years ago I don't think it ment as must as it does today.  At least it didn't for me.  I could use a big old 9" grinder all I wanted without ever thinking about what it might be doing to my exciter.  Last year I let an extra helper that was assigned to me grind off my 200d for every bit of 10 days on 1" plate torch cut pieces (yes I cut them and yes they were rough) .  Shortly after that I found my exciter was messed up man.  It had this big "U" shaped groove wore down in the commutator.  I had to replace the exciter armature.  I don't think I need to tell how much that cost and how much a bummer that was. lolFind out what the duty cycle is for your components and observe them is my best advice I have to offer you.  Doing that will save you trouble and $$.  My experiences alone proves that.  Read your manual and believe it.  My manual stated these facts but I just didn't believe it soon enough to help me.  lolLooking back - it would of been cheaper to buy a small portable generator and let him grind off of that instead of using my welder to grind with.  At least I would of had the generator to use now.    I had to core charge the old armature.  In all my years I have never seen an armature wore down like that one was.  I should of observed my manual and the published duty cycle and I could of prevented that problem I think.  At least thats how it looks to me anyway. lolYou can imagine how the work was going.  I was cutting 1" plate pieces and doing the tacking (had 3 welders to keep busy), he was grinding them as I cut.  He probably started that 9" grinder about 2000 times in a normal 10 hour day and when he was grinding he had to bare down because those cuts were rough man.  (what can I say) lol.   Then I was tacking up while this was all taking place.  Yes I exceeded the published duty cycle by "far". lolBest of luck man!!!!!Last edited by slowhand; 01-05-2011 at 09:14 PM.