I recently bought and installed an Idealarc TIG 300/300 according to Lincoln recommended wiring (200 amp residential service, welder circuit is set up with 125 amp breaker at 230 volts, #3 wire, frame of the welder will be grounded with #6 wire, but have not gotten to that yet).
When the circuit is energized, but the power switch for the machine is OFF, the machine buzzes very loudly - (If I had to guess I would say the buzzing sound must draw about 10 to 40 watts !).
Is this normal for a machine like this? If not, what might be the problem and how could it be fixed. Otherwise, the machine seems to works just fine. I did not notice it buzzing in the shop where I bought it and tried it out, but that was an active machine shop so I probably would not have noticed it either way.
Also, when the machine power switch is OFF the frame/cover is energized with about 2 volts AC tested from frame to ground, or frame to neutral. (As I said, it will be grounded before I fire it up again) is this a cause for concern?
Thanks for you advice.
Tim
By ChenS
Date 03-13-2007 18:38
Edited 03-13-2007 18:42
Hi Tim,
Mine (84' model 8920) buzzes too when On\Off bottom is down and power supply in on, still havent figured it out yet but i will consult my friend who is an electric engineer in the welding equipment area soon , btw do you have a contactor noise when on stick mode idling or while welding on tig(when contactor closes circuit....)? - I've bought a new contactor but haven't replaced it yet since no matter how loud it is, it's still working (and very good actually) and I figured out i'd better not touch something that still works.
In the meanwhile I take the 125 breaker down each time at end of the day until the power draw on the Off mode is solved ,it's a great simple machine however ,even though it does not have the wave balance -it's very powerfull on high Amps and probably more than the declared specs (if you have it with 60Hz input it will get you to 400+Amps on "Max " mode ...
P.S regarding the Grounding thing,
Is it supposed to be hoked up to the frame of the welder? (I don't recall seeing that on the tech manual, but something was mentioned about a Hi frew isolator ,please enlighten me
10X
C.
Chen,
My machine is a 1975 model 7499. The owners manual, availble for all these machines on the Lincoln Electric web site, says to ground the frame - it says this both in the High Frequency Interfereence Protection text box, and in the installation instructions. The machine was not grounded in the shop that I bought it from, but working around a machine hooked to a 125 amp circuit, I'd rather spend the $25 and hour installing the ground and be safe rather than sorry.
As far as the contactor is concerned, I don't have the experience with the machine yet to know all the noises. I just got it weekend before last, and got it hooked up (mostly) last night. I ran the TIG briefly when I was looking to buy it, but am not set up for it at home yet. But I will look into the contactor and see if it is making any noises.
If your electrical engineer friend gives you any insight into the buzzing, I'd apprieciated your passing it on.
Mine is on a 60 Hz service. What the heck are you welding at 400+ amps anyhow? I'm not sure I'll ever get to the Max Amps range; actually sounds kind of scary :)
Regards.
Tim
I have an old Airco 600, this is the same as a Miller 360 ABP. My machine has a small ON / OFF switch that controlls a contactor to turn the machine on & off. There is a transformer that is on any time the breaker is on, and it draws some power. I turn off the breaker when I am not using the machine. I suspect Your machine is similar. By the way, if You havn't removed the sheetmetal and brushed / blown away any acumulated dirt, grit & filings, it is a good idea to do so.
I actually got mine a couple of weeks ago too guys,
Checked it up this morning and around 5amp goes to the rear lower transformator indeed when power switch is at Off,I also recal someone mentioning that these beasts have nasty draw on idling that is part of their ol' tech wisdom.
Anyway I really never got to weld at 400 amp but did some 2.25" thick aluminium casting repair at around 300 amp the other day ,and managed to blow a water hose(probably water pressure was too low and the little fellow melted from the heat output) just where it enters the torch pipe(it was the power's cable hose), since then I keep an eye on the hoses temps and also I hooked up the water suplly externally(not entering the machine ) with a separate valve and a filter whenever the machine is on the water if on:)
Chen, note that the operators manual says that when welding in AC without an Arc Polarizer add on, the machine will draw about 30% higher input, and recommends that if welding above 230 amps AC you go to bigger circuit wire and breaker. Since you didn't trip your breaker, I guess you were OK, but something to consider in the future.
Another interesting thing I have not quite figured out yet. The former owner gave me an original Operator's Manual IM-265-A which says the machine will draw up to 106 amps ("with Cond." which I now figure means with a Power Factor Capacitor) - tag on the machine also says it will draw up to 106 amps.
The IM-265-A manual on the Lincoln site was apparently revised in 1988 - that version says that with a PF Capacitor the machines only draw 86 amps. Someone on another web site suggested that this was a re-calculation to account for the 60% (versus 100% for an electric motor) duty cycle.
Interesting ,it didn't trip my breaker at 9th position on the High mode\ AC,I do have a specially made power supply for the welder straight from the industrial zone power supply to the farm(with 1" thick 3 wires cable straight before and after the breaker ), btw did you ground the work terminal too?
By Tim B
Date 03-15-2007 02:34
Edited 03-15-2007 02:42
I guess I have not thought much about high frequency interferences yet - if I have trouble with the TV or other appliances, I will deal with it then. By work terminal (they call it the "work stud" in the book) I assume they are talking about where the grounding clamp cable attaches?
Re: the higher amp draw welding AC. According you your manual, the max draw w/pf capacitors is 84, welding AC at high amperage should be OK. If it can draw 30% more; 84 amps*1.3 = 111 amps, so it should be OK on your 125 amp breaker.
I have not finished the installation yet, As I have not found the stud on the frame where you are supposed to ground it. I suppose any good connection will do.
BTW, the buzzing in my machine is comming from the auxilliary transformer which, I assume, steps down the 230 volts to 115 for the 115 outlets on the front of the machine. I don't know if they work yet as the fuse is blown.
That 115V transformer powers the contactors, probably the HF circut and some controll circuts within the machine as well as the 115V outlet for the coolant pump. The fuse is so You cant overload it from external loads. By using a transformer the machine can be wired for voltages other than 230 and still have 115V for the components above. What I like about these older machines is that You can understand them and fix them Yourself.
Idle draw: This is due to the power factor capacitors. While at higher output they reduce the amperage drawn by corecting the power factor, the electric line sees them as a load when the transformer is not at higher output. I don't know about the Lincoln machines, but on My Airco the idle load is only a problem when stick welding, as the TIG contactor is on the primary side of the transformer, and the transformer is not energised untill You put the pedal down. If You were not going to use the machine above 1/2 rated output it would probably save power if the PF caps were unhooked, but at full output they reduce the amperage draw about 30%.
Thanks Dave, great info.
Tim
By ChenS
Date 03-15-2007 06:56
great dave ,I guess our Linco's work the same ,
Tim- the terminal for the grounding clamp is the "work" terminal,
g'day,
C.
