Fast Idle & Low Voltage

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I have a Hobart Champion 10,000 that I replaced the board, bridge rectifier, transducer, and idle solenoid in last fall. It sat about 3 months unused, started it up, motor revs. but won't idle down or put out voltage. Worked perfect until now. Any help resolving this problem would be appreciated.
Reply:Kevin, welcome to the forum.Lincoln A/C 225Everlast P/A 200
Reply:Check the condition of the rotor slip rings where the brushes ride and clean with some 120grit then 320 grit sand paper - running or not running depending on your level of comfort working around rotating equipment.Depending on the unit SN, check for blown fuse F1 or open circuit breaker CB4.Check all the terminal connections at the control board for corrosion and the harness plugs to make sure they are properly seated in their receptacles.Check the bulkhead connector of the engine-to-generator harness for poor terminal connections.  In particular bulkhead connector pin #3/wire #20 for battery (+) voltage while unit is cranking and running.  Also check for same battery (+) voltage at control board receptacle RC3 pin #5 while cranking/running.MM200 w/Spoolmatic 1Syncrowave 180SDBobcat 225G Plus - LP/NGMUTT Suitcase WirefeederWC-1S/Spoolmatic 1HF-251D-1PakMaster 100XL '68 Red Face Code #6633 projectStar Jet 21-110

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Reply:Thanks
Reply:I got it up and running, idles, runs, and idles back to normal, but I'm only get about 95V from outlets. I've already checked every connection point I could find, cleaned the slip rings and lifted the brushes thinking maybe they were stuck. So, far everything looks good. The only thing I don't know how to check for sure is the bridge rectifier and transducer. I'm hoping it's just one of those. Also, when engine starts to idle up the CB4 trips. Still get low voltage 95V at ac outlets. Any more advise on the problem at this point. Thanks for the previous advise.Last edited by Kevin B; 05-16-2017 at 03:58 PM.
Reply:Your tripping CB4 could be due to a bad bridge rectifier SR2 (but you already replaced that), a bad CB4 or excessive rotor resistance which should be 14.2 or 18ohms between the slip rings depending on the unit SN which you haven't listed yet.The low AC voltage could be due to slow engine speed.  If you don't have a tachometer you can use a Kill-A-Watt meter (from Home Depot) to set the speed by frequency at the duplex outlets.  Should be set to 62-62.5Hz no load.

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Reply:Got machine back to running like it's supposed to, getting 110V at outlets, but, still low/no weld output, and still tripping CB4.I traced all wires, checked V on them, everything checked correct.I've ordered the bridge rectifier, should be here in a day or two.Is there anything besides rectifier that could still be a possibility?If I let machine go to idle and re-set CB4, machine bogs down for a 2-3 secs. and trips CB4
Reply:What were your AC voltage readings at the input to bridge rectifier SR2?DCV at SR2 (+) and (-)?Did you confirm you have SR2 connected correctly?MM200 w/Spoolmatic 1Syncrowave 180SDBobcat 225G Plus - LP/NGMUTT Suitcase WirefeederWC-1S/Spoolmatic 1HF-251D-1PakMaster 100XL '68 Red Face Code #6633 projectStar Jet 21-110

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Reply:Pretty sure SR2 is hooked correct.  If you don't mind give me wire #'s and which terminal each hooks to. I know the flat corner is positive and opposite corner is negative, the other two shouldn't matter. Correct me if I'm wrong. Thanks again!!!
Reply:You are correct.#21 = (+)#33 = (-)#22/29 = AC (~)Do you have a meter with diode test setting to check it?MM200 w/Spoolmatic 1Syncrowave 180SDBobcat 225G Plus - LP/NGMUTT Suitcase WirefeederWC-1S/Spoolmatic 1HF-251D-1PakMaster 100XL '68 Red Face Code #6633 projectStar Jet 21-110

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Reply:Yes, it checks good, but, I'm thinking that maybe when a load is put on it, it fails.Should have a new part today or Monday. If that doesn't fix it, I guess I'll try the breaker.Any other suggestions as what's my next best guess ?I went over the board and everything checks good there as well, with the exception of being able to check the capacitors, they look ok though.
Reply:Don't rule out a weak CB4 as I stated earlier.  You could disconnect it and by-pass it with a $2 fuse holder and fuse to see if it blows too.If it does, you'll need to dig deeper.  If not, it's safe to say CB4 is bad.MM200 w/Spoolmatic 1Syncrowave 180SDBobcat 225G Plus - LP/NGMUTT Suitcase WirefeederWC-1S/Spoolmatic 1HF-251D-1PakMaster 100XL '68 Red Face Code #6633 projectStar Jet 21-110

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Reply:I checked the wiring on SR2 and it was correct.Fired it up and was getting correct voltage from AC outlets and 50V on DC, is 50V what it should be, doesn't seem right to me, but, it's consistent at 50-52.No matter where I to turn Amps. to it either cold welds or sticks.Checked the potentiometer, getting variable resistance when turning it, it's new as well. Thought maybe some bad rods, I tried 6011, 6013, 7018, etc. with no luck, Straight or Reversed.After about 10 mins. of running a grinder and trying to use stick, the voltage dropped on AC to 93V. So, I'm hoping the SR2 is just breaking down under load. Maybe the part will be here Monday and will fix it, but, if not I'll get a fuse holder and try that. Thanks for all your help this far.
Reply:PM me an email address and I'll send you a unit information file that is too large to post to the forum.MM200 w/Spoolmatic 1Syncrowave 180SDBobcat 225G Plus - LP/NGMUTT Suitcase WirefeederWC-1S/Spoolmatic 1HF-251D-1PakMaster 100XL '68 Red Face Code #6633 projectStar Jet 21-110

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Reply:Still don't know your unit SN and depending on what that is, AC voltage at the receptacles should be either 114VAC or 122VAC and either 60VDC or 70VDC Open Circuit Voltage (OCV) at the weld output studs.  So, I'd say your engine speed is still a little slow.The cold weld performance could be due to a defective hall device (LEM) that senses weld output and signals the control board that would then either increase or decrease rotor field voltage.  The information I can send you covers troubleshooting this but you can start by checking the LEM harness plug terminals for corroded/poor connections.MM200 w/Spoolmatic 1Syncrowave 180SDBobcat 225G Plus - LP/NGMUTT Suitcase WirefeederWC-1S/Spoolmatic 1HF-251D-1PakMaster 100XL '68 Red Face Code #6633 projectStar Jet 21-110

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Reply:wow, thats some comprehensive support there. My respect for your efforts duaneb55
Reply:HOBART CHAMPION 10,000 with 25hp KohlerStock # (500434)SN (LK150516Y)Thanks duaneb55, I've got another meter on the way, with HZ setting on it as well as a bridge rectifier, and a in-line fuse.My meter is a Professional Craftsman that I got 18yr ago while taking electrical, time for updated version anyways. I set the rpm's with a digital timing light that has 2cyl. & 4cyl. setting.Hopefully I have some good news to report back later today.I also meant to mention, looks like a thyrector/resistor on SR1, between the Pos. & Neg. plate.Meter makes the trip through it, so, I'm guessing it's ok, but, my manual doesn't list this part and I don't have any info. for it.Do you know what I'm referring to ?***************Welcome downhand,Looks like you/we found the right sight for info. for whatever question you can throw out there.By far the most knowledgable, most informative persons' I've came across.
Reply:Still need you to PM me an email address.  Gotta make a little day trip so I may be awhile getting back to you once I have an email address.MM200 w/Spoolmatic 1Syncrowave 180SDBobcat 225G Plus - LP/NGMUTT Suitcase WirefeederWC-1S/Spoolmatic 1HF-251D-1PakMaster 100XL '68 Red Face Code #6633 projectStar Jet 21-110

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Reply:Got machine running and putting out correct voltage on both AC and DC. Plugged in a grinder, 7 amp draw and was working good.So, While running that grinder I plugged in another 7 amp and ran both at same time, working good for probably 30-45 seconds, then, blew D28 on the Control Board. Any idea as to why this happened and a possible fix.I have another diode ordered and will replace as soon as it gets here.Do you think it'll be safe to try to run again, or am I asking for trouble ?
Reply:Check for a shorted SR2 between one/both AC inputs and the (+) output.MM200 w/Spoolmatic 1Syncrowave 180SDBobcat 225G Plus - LP/NGMUTT Suitcase WirefeederWC-1S/Spoolmatic 1HF-251D-1PakMaster 100XL '68 Red Face Code #6633 projectStar Jet 21-110

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Reply:I replaced the diode(D28) and machine is now running.The problem now, is, CB4 keeps tripping as soon as motor revs. and I still get voltage unless I turn off the main breaker (96-98V AC) and 50V DC, with 62.5-65Hz in the run position.Back it off to idle and all the numbers cut in half.Any idea where I go from here.Thanks for all the help.
Reply:Did you find a solution to the problem. I have a Hobart 10,000 that's doing the same thing.