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I finally found it.   I've spent the last few weeks looking for an older machine for TIG and I finally found something local.  I've only got a 50A circuit to run it on, so I won't be able to crank it all the way up, but I'm now the proud owner of a 1999 vintage Syncrowave 250.Its got a little rust around the base, the amp and voltage meter faces are hazed over, but otherwise looks pretty good.  No cart, leads, torch or cooler, but for the price I can afford to pick up the accessories and still be in the range of complete packages that I would have had to drive 4 hours to see.  I've known the guy for a while and he gave me a DOA full money back guarantee since I couldn't try it out.  This isn't the guy that also had the Econotig I'd talked about before, that Syncrowave was practically brand new.  Its got the 14 pin Remote connector and the gas valve, post-flow timer, but no pre-flow.I pulled the covers off and cleaned it out well.  It was a little overdue for a dustoff.  I'd run into somebody that had a torch and pedal for sale, so now I'm waiting to hear back from him.  This is almost like having to wait at the top of the stairs on Christmas morning.  I gotta grab a couple of connectors to wire up the power cord, then I can at least turn it on and listen to it hum a little, lol and make sure it doesn't make any smoke.  I checked the voltage jumpers, all good there, and next I'm going to verify the spark gap at 0.008.    Anything else I should check before I turn it on?  Wasn't even gonna turn on the HF off til I get the torch.  I'm a little paranoid about my neighbors getting HF interference.  I'm the end 1/3 of a 75' wide metal building.  The middle third is just storage for a mattress store, so I don't think they've got any electronics in there.  The guy on the other end is a CV axle rebuild shop and he's got a desktop pc in there, and I've got a desktop pc in my office.  His pc is probably about 35' from my welder, and mine is about 15' away.  I can't do much about the recommended 50' clearance.  My power from the main panel to the machine is through a 75' run of EMT conduit, so I think I'll be protected from radiating out back in that direction.  Should I go to the trouble of drilling a hole in my slab so I can install an extra ground rod close to my welder?  Thinking when I'm ready to try the HF out I'll wait til the evening when all the businesses close are closed.  Is a portable AM radio a good "test" device as a crude check for RF problems?Thanks for everyone's help in getting me this far.  I've really enjoyed this site.- BillCentury Wire Feed 140 MIG, Snap-on MM140SL MIG, Syncrowave 250, Airco 225 MSM Stinger, Victor O/A rigGrizzly 4" x 6" Bandsaw, Milwaukee Portaband and Dewalt 14" ChopsawAtlas 12"x36" LatheCentral Hydraulics 20T Shop PressToo Many Hand Tools
Reply:I have a 1992 model that, as per the original owner (who was a gent and had zero reason to lie), only saw service doing small jobs.  It came with a 125 amp air cooled torch that he said was his original and said the most he ever turned it up to was 105 amp output on DC.  I asked him about AC and he said he never tried it.  I'm on a 50 amp circuit as well.  After blowing the breaker a bunch of time at IDLE, I called Miller and disconnected the Power Factor Correction (PFC).  The PFC is a group of capacitors that link to the main power input board where the voltage jumpers are installed.  You disconnect the 2 wires from the board, make a diagram of where they were installed with a sharpee on the inside of the wrapper.  Fold them out of the way and tape them up.With the PFC at 230 volts, the machine pulls 74 amps at idle!  it reduces the power needed to run balls to the wall, but after asking a bunch of questions on forums, most agreed that it didn't really help much unless you're doing major production with it.   With it disconnected, IIRC, it pull 4 amps at idle and 54 amps at WOT.  I think it was 42-48 amps at WOT with the PFC.  I havent blown my breaker since, even using 200 amps on Aluminum.TA Arcmaster 300CM3XMT 304S22P12 suitcase feederX-Treme 12VSOptima pulserTA161SMaxstar 150STLHypertherm PM45OP setupStihl 020AVP, 039, 066 Magnum
Reply:Oh, and one other thing.I had alot of problems with the torch adaptor arcing to the unit.  There's not much room around the connection.   I eventually wound up running a piece of 2/0 cable with a weldon lug to the output post, then a Tweco disconnect.   There wasn't  anyway tp get the aircolled torch adapter to fit in there without arcing, at least not for me.Good luck with your nearly bulletproof machine.TA Arcmaster 300CM3XMT 304S22P12 suitcase feederX-Treme 12VSOptima pulserTA161SMaxstar 150STLHypertherm PM45OP setupStihl 020AVP, 039, 066 Magnum
Reply:Thanks DRF for those tips.  Don't think mine has PFC capacitors, and I had actually been thinking of ADDING them to reduce the amps.  I would never have though they'd have increased the amps at idle.  The specs show that with PFC the full throttle amps are significantly lower, so I bet once you get past idle they drop to a minimum closer to the 5 you saw, and then climb back up to the maximum at full output.  If the breaker was adequately sized then it wouldn't trip the breaker when you power it up.  I do recall that too much PFC is a bad thing, and this might be an example.  I did a project installing PFC caps in a plant and the cheaper option was to install a bank of large ones in the motor control center, as opposed to installing lots of small ones attached directly to the big motors.  They did warn us with the MCC route we needed to disconnect them if we shut down that department, then remember to turn them back on at startup.  On this welder it was probably too complicated a design to have the PFC caps come online one at a time as they were needed, so they compromised and have them all connected the whole time, with that unwanted side effect. If mine does have them, I might disconnect them completely now, and later on play with how it acts with only some of them connected.WOW I just looked at the specs again.  Idle with no PFC is like 4 amps (right where you said), but with PFC idle is 49 amps, and the really unusual part is max amps with PFC is 48, 1 amp lower than idle.  It might be with PFC the input amps is a flat curve.  It is worth it as long as you don't pop the breaker at idle, cause max amps is 74 for non-PFC vs 48 with PFC, that's a 35% cost savings on your power bill.  If you're bored one day you might try hooking back up just one of the caps and compare input amps at some fixed output.  It could be you could take advantage of some of your PFC caps and not pop the breaker.Anyone else had this idle problem popping the breaker and played with removing just some of the PFC caps from the circuit?Century Wire Feed 140 MIG, Snap-on MM140SL MIG, Syncrowave 250, Airco 225 MSM Stinger, Victor O/A rigGrizzly 4" x 6" Bandsaw, Milwaukee Portaband and Dewalt 14" ChopsawAtlas 12"x36" LatheCentral Hydraulics 20T Shop PressToo Many Hand Tools
Reply:I don't want to be an azz, but I have considerable experience with PFC, and non PFC tigs.If you are popping breakers at idle, and not at surge, you have something very wrong. Capacitors naturally age and break down over time. I think you have bad capacitors, or they are shorted with metal dust.The idea with pfcs it to offset the surge when you start an arc, which overloads your breaker. Therefore you can get by with smaller breakers.I would have your capacitors checked out, and see if they were installed correctly in the first place. Miller offered PFCs as an option, and as a retrofit kit for many years. I found that out the hard way when I bought my first syncrowave. I was popping a 90 amp breaker all to often, and was told the retrofit kit was over $1k. Worked like charm and never threw the breaker again, but I never bought a sync again either.A syncrowave without PFC is like a day without sunshine.Weld like a "WELDOR", not a wel-"DERR" MillerDynasty700DX,Dynasty350DX4ea,Dynasty200DX,Li  ncolnSW200-2ea.,MillerMatic350P,MillerMatic200w/spoolgun,MKCobraMig260,Lincoln SP-170T,PlasmaCam/Hypertherm1250,HFProTig2ea,MigMax1ea.
Reply:Originally Posted by Drf255I have a 1992 model that, as per the original owner (who was a gent and had zero reason to lie), only saw service doing small jobs.  It came with a 125 amp air cooled torch that he said was his original and said the most he ever turned it up to was 105 amp output on DC.  I asked him about AC and he said he never tried it.  I'm on a 50 amp circuit as well.  After blowing the breaker a bunch of time at IDLE, I called Miller and disconnected the Power Factor Correction (PFC).  The PFC is a group of capacitors that link to the main power input board where the voltage jumpers are installed.  You disconnect the 2 wires from the board, make a diagram of where they were installed with a sharpee on the inside of the wrapper.  Fold them out of the way and tape them up.With the PFC at 230 volts, the machine pulls 74 amps at idle!  it reduces the power needed to run balls to the wall, but after asking a bunch of questions on forums, most agreed that it didn't really help much unless you're doing major production with it.   With it disconnected, IIRC, it pull 4 amps at idle and 54 amps at WOT.  I think it was 42-48 amps at WOT with the PFC.  I havent blown my breaker since, even using 200 amps on Aluminum.
Reply:All I can say is that on a 50 amp breaker, I would blow it at idle and not under load, ever.  By all means, if you have PFC continue to use it.  I was just trying to share my own experience.  Below is the thread I got info from, as well as talking to Milker about it.  They confirmed it wad the PFC.  If I were to run a 100 amp circuit, I'd hook it back up.  For my use it works great without it.  http://weldingweb.com/vbb/showthread.php?t=58883TA Arcmaster 300CM3XMT 304S22P12 suitcase feederX-Treme 12VSOptima pulserTA161SMaxstar 150STLHypertherm PM45OP setupStihl 020AVP, 039, 066 Magnum
Reply:Here is something to think about. Put a 30 amp contactor in the pfc capacitor circuit.Wire it to be controlled by the gas valve post flow timer. This will switch the caps in just before you need them and switch them out when you don't. Asked Miller about this and they didn't see why it wouldn't work. Just add a little extra preflow.
Reply:Originally Posted by ccawgcHere is something to think about. Put a 30 amp contactor in the pfc capacitor circuit.Wire it to be controlled by the gas valve post flow timer. This will switch the caps in just before you need them and switch them out when you don't. Asked Miller about this and they didn't see why it wouldn't work. Just add a little extra preflow.
Reply:People's experience with the PFC capacitors is all very interesting.  Some people pop breakers only with them, some the opposite.  I suspect the reason may be the difference in each person's baseline power factor, that is what the local power factor was before the welder was turned on.  Electric motors and things like welders pull the power factor down, capacitors bring it back up, and things like incandescent lights which are purely resistive load don't affect the power factor.  The other thread that drf linked us to gives some of the theory about power factors but its likely that its still clear as mud to most people after reading it.  A part that didn't make it well to the discussion is the difference between apparent power and real power.  With a lagging power factor (the condition you normally see) apparent power is always less than real power.  Your electric meter measures real power, but the breaker responds to apparent amps.  Power companies don't like low power factor because it cause greater losses in their transmission lines, so they have less watts available to sell.  If we're on this forum we probably understand that AC voltage cycles back and forth between positive to negative.  That's the curvy sign wave function.  The curvy sine wave graph we see representing AC voltage can be drawn both for volts and amps.  (ok hold on this is where it gets a little wierd)  If power factor is perfect the two graphs align with each other, amps and volts are going up and down together.  When the power factor goes down, the amp curve starts to lag in time behind the volts.  This always happens when you have AC current going through a motor or transformer.  We all know how a flywheel helps smooth out the ouput power of  multi-cylinder engine, well the transformer has a similar effect on the cycling AC current.  Imagine the volts go through easily, but the amps have a hard time switching directions so they get slowed down a little.  You're trying to get a certain amount of power out of the welder in heat.  Heat is work in this situation, and electrical work is calculated by the sum of the product of amps and volts over the whole cycle positive to negative and back.  This is where some confusion comes in.  Few of us have power factor meters, at best we have volt and amp meters, so all we can calculate is volts and apparent amps, which together give apparent power.  Apparent amps are always higher than real amps. Real power is what gives you the heat at the end of your torch or rod (and what we get charged by on electric bill), so normally it benefits us to have proper power factor as it "takes less amps through our breaker to get the same heat at the torch".  So for most people using PFC is better, but drf has proven this isn't always the case.DRf has proven that there are some cases where the use of PFC caps in his machine caused a problem.  I don't think it was failed capacitors.  They typically fail open which means they do nothing.  If they fail to a short, then they generally explode and he'd have noticed that.  Too much power factor correction gives you the "possibility" of causing harmonics.  Might happen and it might not, and this is something beyond the capability of anything short of a electrical engineer experienced in power transmission.  Harmonics are caused by wierd interactions with other pieces of equipment nearby, and when it happens a typical symptom is popping the breaker.  This goes along with that old addage, if it hurts, don't do it.  Add this to the end of your list of troubleshooting popping breakers on welding machines, try disconnect some or all of the PFC caps.DRF if there are multiple caps in the PFC section, can you try running with just one and see what it does?A nice experiment would be for someone with PFC to watch their electric meter as they went from idle up to 200A or so.  Does it go faster or hold steady as the amps listed in the specs indicate?  Electric meter reads Real power so I think you should see it go up proportionally with welder output amps.An interesting aside.  Lightly loaded electric motors hurt your PF.  If you put a higher HP motor on than you need, or operate it under light load most of the time then you'll have a lower PF than a motor running at full load.Century Wire Feed 140 MIG, Snap-on MM140SL MIG, Syncrowave 250, Airco 225 MSM Stinger, Victor O/A rigGrizzly 4" x 6" Bandsaw, Milwaukee Portaband and Dewalt 14" ChopsawAtlas 12"x36" LatheCentral Hydraulics 20T Shop PressToo Many Hand Tools
Reply:DRF I've been doing some more reading on using PFC's in welders in general and about your unsual problem with popping the breaker at idle.  Even though it doesn't meet the recommendations, lots of people succesfully run the Syncrowave 250 on 50A circuits, so that "shouldn't" be your issue.  It appears that everyone with PFC's installed  (and as documented in the Miller manual) experiences the high measured amps at idle, but you said you measured 74A at idle.  74A is higher than expected and significantly enough higher than the breaker's 50A rating to trip it if you hold it for a few minutes.  Something is unusual in your particular installation, something else that it affecting the power factor, causing too much power factor adjustment.  As I said before too much power factor correction can cause problems, particularly with harmonics which are not easy to track down, and those harmonics CAN trip breakers.Reading on other forums I've seen where people have installed four 150 mfd capacitors for PFC with no problems, and in another case I read where someone who requested the PFC option ended up with two 150 mfd's.  No explanation of why the difference.  Both were on Syncrowave 250's.  My manual lists PFC caps as an option and the parts list doesn't include them.  I also understand that some PFC caps only have part numbers and aren't labeled with mfd's, so it may be hard to check what you have against other people.  DRF and anyone else with PFC's, can you tell me what your's has installed?  The number and any mfd markings.  Although I haven't seen exactly how they're wired together in the set, they should be wired in parallel, and it should relatively be easy to disconnect them (by unplugging connectors so you could reverse the process later) one at a time from the circuit, reducing your PFC  adjustment a step at a time until you get your idle amps back in the normal range so you don't trip your breaker.  You never know your capacitors might have been a field install by someone with a 100A service who ran WOT all the time and they put in "a little extra."  Might be one less cap does the trick.The concept of Real and Apparent power is difficult to understand and I may not have done it justice in my previous post, but those high idle amps are mostly Apparent power and don't cost you at face value on your electric bill, maybe a tad increase, but not what you'd expect from the amp reading you measure.  The lower top end amps (running WOT) that ARE the payback from having PFC's DO DEFINITELY SAVE you on your electric bill, so unless you're having breaker problems I really feel its in your interest to use the PFC's if your machine has them.  Also if you have a problem like DRF, just disconnect the capacitors one at a time until the problem goes away.  For people that are limited to a 50A circuit, then adding PFC to a machine that didn't previously have them will let you run higher duty cycle at higher output since the PFC's do reduce the primary side amps for the same welder output by about 1/3.  And that will save on your electric bill.If you really feel you need different amount of PFC depending on what you're doing, there are other threads where people discuss methods to switch PFC's in and out depending on load. Its a pain to open the cover and fiddle with the wires when you're going to be running light duty one day, and WOT another, so having some kind of external switches would be nice. That's a sticky issue because of the power storage nature of capacitors.  If you open a circuit with a charged capacitor, you tend to get an arc across the contacts, whether its in a heavy duty contactor or a manual switch.  Imagine that, an arc, we all know what those can do right (burn up the contacts).  Heavy duty contactors that can give reasonable life under those conditions are expensive.  The PFC capacitors are connected on the primary side of the main transformer, just downstream of the on/off switch, so they charge up as soon as you flip the power switch on.  I found an old thread where a guy used multiple manual switches to bring in however many he felt he needed, but he didn't give any details.  If you always did your PFC in/out switching with the main power switch OFF, I think that could be practical.  If you're using a 230v circuit, then those standard 25A 250VAC panel mounted type toggle switches would probably give pretty good service.  Worth a try if you feel qualified to do a wiring modification on what's a relatively straight forward section of the circuit.Century Wire Feed 140 MIG, Snap-on MM140SL MIG, Syncrowave 250, Airco 225 MSM Stinger, Victor O/A rigGrizzly 4" x 6" Bandsaw, Milwaukee Portaband and Dewalt 14" ChopsawAtlas 12"x36" LatheCentral Hydraulics 20T Shop PressToo Many Hand Tools
Reply:You have a much better understanding of the PFC theory than I do.  I misspoke when I said 74 amps.  As you said, it was like 51 amps with the PFC at idle.  I think it was 74 vs 48 at max load with and without the PFC.  I didn't have the manual open at that point.  I may hook them back up with an on/off switch on one lead.  It was just highly annoying to pop the breaker with the machine idling.  It never happened at load, as I was prolly only pulling around 30 amps.  I'd have to get up, walk 100' to my basement door and go down to reset it.  I actually have 2 50 amp breakers on the circuit.  One feeds the sub panel, one in the sub panel.  I may reconnect the PFC and replace both breakers and give it a go.  I haven't been in my machine for a few months, but IIRC, there were 6 or 8 capacitors the size of tall boys on the lower back panel of the machine.TA Arcmaster 300CM3XMT 304S22P12 suitcase feederX-Treme 12VSOptima pulserTA161SMaxstar 150STLHypertherm PM45OP setupStihl 020AVP, 039, 066 Magnum
Reply:Ok I did an experiment tonight.  I found a few 200 mfd 330 volt AC motor run capacitors on fleabay for $28.  From what I found reading online, Miller would charge $400 to 500 for a set and I can't afford that kind of experiment.  I'm sure mine aren't as beefy, and they aren't going to be adequate if I for some reason I wanted to run it on 460 volts, but I wanted to play.I hooked 3 of my capacitors up in parallel (600 mfd total) to the terminal strip where the wires from the power switch connect to the transformer leads, so they power up when I flip the switch to on.  I read where someone found the necessary spare leads tucked neatly next to the transformer, but I wasn't so lucky.  I used 12 gauge wire and crimpon connectors for my harness.  I'm on a 50A 220 volt circuit, and before attaching the capacitors I'd measured my idle amps at 4.  When I flipped the switch on tonight I measured 55 amps at idle, close to what Drf measured.  I didn't wait for it to pop my breaker before turning it off.  I disconnected one capacitor bringing me to 400 mfd and powered it back up (YES I waited a few minutes to make sure the charge bled off BEFORE I removed it).  38 amps this time when I turned it on.  Removed a second capacitor bringing me down to 200 mfd and I got 19 amps at idle this time.  I plan on going back to 2 which will give me 400mfd, and leave it at that.Seems to me this is proof positive that running this machine on 220v with a 50A breaker and a full bank of PFC's, you WILL pop the breaker if you sit idling too long.  It would SEEM that anyone with a 60A or higher breaker wouldn't have this issue.  We heard from shovelon (above) who was popping his 90A breaker, but that was BEFORE he added his PFC's, and he didn't exactly say, but I think he was popping it while running wide open?   PFC's are designed to reduce amps at full output.I started out my experiment with 600 mfd because I saw two references to people saying they had 600 mfd.  I saw no other numbers quoted.  The 55A I measured was a little higher than the 51A listed in the specs for a PFC equipped machine at idle and 220v.  Off the cuff gestimating I'd say that 550 mfd would have put me closer to the 51 spec'd, and close enough to the rating of my breaker that it would have taken a lot of idling to pop it.  500 mfd would have been more comfortable at idle while still helping quite a bit on the top end.  It'd be nice to hear from anyone with Miller installed PFC's whether or not theirs are marked with mfd's on the label, and what they have.CAUTION:  Anyone with PFC's popping breakers at idle, the good news is that you shouldn't need to remove all your PFC's to solve the problem, BUT you have to look closely at how yours are hooked up, so you remove the right ones.  I looked at a schematics on a couple of similar machines and they aren't necessarily all hooked up the same.  I cheated a little by connecting directly to the terminals coming off the power switch.  When you put 2 capacitors in parallel you double the mfd's.  When you put 2 in series you double the voltage rating keeping the mfd the same.  I appears that sometimes the PFC's are connected to the terminal strip in two parallel sets of two in series (total of 4) so that depending on how you set the voltage jumpers (230 or 460) it puts the 2 sets of capacitors either in parallel for 230v, or in series for 460v.  I'm betting the only ones of us having the problem are running 220v, so my suggestion is to arrange them so you have enough in parallel to give you about 400 mfd, and enough in series to give you at least 300 volts.  The voltage ratings will likely be sufficient so you don't have to put any in series.  If you're not sure how to do it, ASK (either your electrician buddy,here or call Miller).TIPs on finding your own capacitors if you wallet is too light to ask Miller for them:  Use motor RUN capacitors, not START capacitors.  Look for metal cased (usually aluminum) capacitors for better heat dissipation (not the phenolic ones that look kinda like black plastic).  Get a voltage rating of a little higher than what you're running at (they'll last longer).Century Wire Feed 140 MIG, Snap-on MM140SL MIG, Syncrowave 250, Airco 225 MSM Stinger, Victor O/A rigGrizzly 4" x 6" Bandsaw, Milwaukee Portaband and Dewalt 14" ChopsawAtlas 12"x36" LatheCentral Hydraulics 20T Shop PressToo Many Hand Tools
Reply:Great info.  I'm in the process of getting together material fo a 100 amp circuit in my garage, but I'm certainly gonna reconnect my PFC and remove 2 caps first and see how she goes on the 50 A circuit.TA Arcmaster 300CM3XMT 304S22P12 suitcase feederX-Treme 12VSOptima pulserTA161SMaxstar 150STLHypertherm PM45OP setupStihl 020AVP, 039, 066 Magnum
Reply:Ok, I still think my test where I measured the idle amps with various amounts of capacitors online was valid, but the capacitors I bought didn't hold up under load.  I burnt a few rods last night, and literally smoked my capacitors.  They didn't catch fire, but they got so hot that the dielectric oil inside was vaporizing and coming out the back of the welder.  I was running the welder at 100 amps AC mode, never even warmed up the machine enough for the fan to come on.  I didn't have anyone with me to read the machine input amps, so I didn't get any data on the benefits of the capacitors.  I don't think the PFC's actually failed, but in another minute or two we might have had something a little more exciting than the blue smoke (yeah it was kinda blue like they say).The ones I smoked were the phenolic case capacitors that I said NOT to get, but this was just an experiment and I was controlling costs.  They were rated at 60C and the cases weren't so hot I couldn't hold them when I pulled them out, but then the phenolic is a good insulator, so they may have been much hotter inside.  There were spattered drops of the oil scattered over the tops of the capacitors and around them on the floor of the machine case, so it was like the oil was boiling inside them.  Somebody please get me a pic of some Miller installed capacitors, and even better some specs from the label.Anyone out there who's disconnected their PFC's like to work a deal?  I'd be willing to help guide you through re-connecting half of yours so you can get part of the high end benefit without popping your breaker at idle, in exchange for you offering me your now "spare" capacitors at a reasonable price.  Send me a PM.Century Wire Feed 140 MIG, Snap-on MM140SL MIG, Syncrowave 250, Airco 225 MSM Stinger, Victor O/A rigGrizzly 4" x 6" Bandsaw, Milwaukee Portaband and Dewalt 14" ChopsawAtlas 12"x36" LatheCentral Hydraulics 20T Shop PressToo Many Hand Tools