plasma cutter operation trouble , help

Hi,

I purchased a new miller spectrum 375 plasma cutter ran into a few problems already or may be I am just too green .

operation seems simple so not sure what is wrong

2 problems.....here it goes.

1; when making a cut it cuts crocked- in a slight side angle

2 ; runs just fine on a 110V circuit , but not on 220V I wired in a new 220V circuit for the welder and same circuit is used for the plasma cutter. but has a a seperate recepticle . the welder works great.

when running the cutter from a 220 V (switch in the back flipped to

230V) it cuts 1-2 inches and shuts off and green "POWER light " is flashing. if I turn off the machine and back on it may cut a few inches more but shuts off again.

flip the switch in the back to 110V and plug it in 110V and it runs along just fine.

the manual does not give much detail on the problem other than check to make sure the switch inthe back is in the right position.

can some one shine some ligh on this.

thanks

Reply to
acrobat-ants
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What is the metal type and thickness ? Is the workpiece grounded properly ? (If it is not grounded you will just get a pilot arc for a few seconds and then it will shut off.) The machine could possibly be defective. Check with your dealer.

Call 920-734-9821 for Miller Tech support or

Send it back and get a Hypertherm ..... :)

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Reply to
Jim

thanks good one .... :-)

almost fall for that i went to hypertherm web site , and looked , they sell the same thing but they call it powermax 380. called tech support they said try it in a different circuit of 230V.

by the way the metal is mild steel and sta>What is the metal type and thickness ?

Reply to
acrobat-ants

Do you use the same cord & plug for 110V & 220V? Sounds like either your outlet or your cord are wired incorrectly. What type of outlet are you using for 220V?

Do you have 110V from each main contact to ground? Do you have 220V between the two main contacts?

Best Regards, Keith Marshall snipped-for-privacy@progressivelogic.com

"I'm not grown up enough to be so old!"

Reply to
Keith Marshall

I am using the same cord which came with the machine it has a 110V

20 amp style plug ad it is plugged into a short extention converting from a 110 recepticle to a 220 plug.

there is 245 V across the 2 main (no Load ) and the neutral is connected to neutral in the sub panel if I meassure from each hot leg to neutral , I get 124V

metal electrical wall box is grounded to ground via ground at the sub panel.

I removed the sheet metal skin from the cutter . to see if there is a jumper for 208- 230 V , did not see it. factory cord has 3 wires going to the mechanical 115-230 switch in the back black, white and green bolted to the cutter chassis.

I assume that in 115 V mode it only use 1 hot (black ) and switching white to neutral or ground completing 115 V circuit. when the mechanical switche is thrown to 220 V position , it is utilizing 1 hot (black ) 1 hot (white ) and 1 neutral , making it a

220 V circuit just like the welder has.

where am I wrong ?

I've check to see if the 110V socket not commonly grounded between groung and neutral.

thanks

Reply to
acrobat-ants

hmmm; wonder if the 248 is out of the % of allowable voltage variance (+10% = 242)

Reply to
dogalone

could be , but 240 + is a no load voltage when the machine is unpluged measured at the socket , i would think it will drop once the cutting is begins.

Reply to
acrobat-ants

not really familiar with capacitive resistances/inductance, but had thought AC circuits to be "voltage preserving"

Reply to
dogalone

white to neutral or ground completing 115 V circuit. when the mechanical switche is thrown to 220 V position , it is utilizing 1 hot (black ) 1 hot (white ) and 1 neutral , making it a

220 V circuit just like the welder has.
Reply to
Keith Marshall

Reply to
acrobat-ants

ok, I am confused now, ground = earth ground a big copper/brass rod driven 10 + feet deep in the ground neutral = goes back to the transformer /power company they are tied together in the main panel.

to me , if they are tied to gether with a solid bar to me it seem as the same circuit yet called different name. it is 2 circuit for safety reasons.

correct me if I am wrong and for the other reader who may also benefit from this topic. in a 110 circuit,

1 hot = feed 1 neutral = return makes the light or electric motor work 1 ground as a safety

in 220 V

1 hot +1 hot completes the circuit and makes the motor or heater run , 1 ground for safety.

so a sub panel shoul get ????? a ground ? and only ground ? no neutral?

so are you saying if my 220 V circiut would only get 2 hot and a ground , may problem would go away ?

I need this plasmacutter to run off of 220V circuit , and don't want to drive back to the dealer.

thanks

PS: the sub panel i wired in is the 2nd sub in the house , the original sub panels ground wire (?) goes to the neutral terminal in the main panel right where the big solid bar shoots over to ground.

Reply to
acrobat-ants

if your 220 welder is working fine on it, that should be working on it (regardless of how it is wired at the factory on the inside, which i would doubt you are supposed to have to mess with).

for "weather-tite" you might want to run an other-than-green ground, but it would seem your black/white 220 w/green ground should be doing the job...

Reply to
dogalone

no neutral? >

Reply to
Keith Marshall

The ground rod is the return, you get two hot wires from the power company with single phase 120/240, Look in the main panel or meter base and you will see only two hots comming in. The "neutral " wire is connected to the ground rod through a suitably sized grounding electrode conductor.

The ground and the neutral are bonded at the main panel and the main panel only. The neutral is the primary path to ground, via the grounding electrode. The ground or green wire is the equipment ground.

Correct, mostly. The ground wire has specific purposes, see below.

A sub-fed panel should get two hots from two seperate phases, a neutral and a ground for 120/240 volts. I am not sure what you are calling a sub panel.

In the sub-fed panels you should have a suitably sized neutral from the main panel and a suitably sized ground from the main panel. In the sub-fed panel the ground or green wire and the neutral are kept SEPERATE. They white goes to the neutral buss and the ground goes to the ground buss and they are NOT bonded together. Look those up in the National Electrical Code book. Grounding is article 250. Most of what you are asking about is in article 250.

The neutral (actually called the grounded conductor) is the primary path to ground, this is why it is bonded in the main panel. The smaller or green wire(called the grounding conductor) is the secondary path to ground or equipment ground in case the equipment becomes energized.

From what you describe, the cord to the cutter only has three wires. In 120 mode those would be a black , white and a green. Black is hot, white is neutral and green is ground. In 220 mode that would change to black is hot, white is hot and green is ground.

I am not sure what the "converter" is you are using. it should have a normal 120 volt looking receptacle on one end that you plug the cutter into and then a male connector of some type on the other. This is where the white wire gets changed from a grounded conductor into a "hot" wire. With the converter or adapter unplugged use a continuity meter and check it out. Ground to ground should ring out. Black or the shorter slot in the normal looking receptacle should ring out to one on the other side and not to ground. White or the longer slot in the normal looking receptacle should ring out to the other side and not to ground. NONE of the wires should have continuity between them, black to white or white to ground or black to ground should NOT ring out.

If I am correct the other side should have two blades like - - this and below those are the ground U.

At the receptacle in the wall those two - - should be hot, both of them and you should have ~220 volts if you put a volt meter between them. You should have ~120 volts from either - to the ground U. This is for an air conditioning type receptacle.

You may have a setup like \ / and an angle or small L for the ground. The \ and / are hot and the L is ground, this would be for a dryer outlet.

A range outlet will have a / \ and a | and can have a smaller angle. The / and \ are hot. The | is neutral and the smaller angle is the ground.

Keith described exactly how the 120/240 volt switch in the cutter works.

Trouble shooting method: Starting at the wall outlet, check for power on the proper blades, check that they are 240 between the two hots and 120 between the hots and ground.

Plug in the adapter deal you have, check that you have 240 volts between the short and long slot on the other end or the female side. Check that you have 120 between those and the ground U.

If you dare and at your own risk with the power on, check that you have 240 between the white and black wires and 120 between those and the ground wire inside the cutter. Try measuring the voltage from the metal case to the ground wire, it should be zero but you never know.

Stop where you don't get the proper voltages. Turn the breaker OFF. Fix or replace where you got the wrong readings. If everything is ok all the way to the inside of the cutter then the cutter has a problem. If the switch is one of those without a handle and you slide it over then make sure it is slid all the way over.

If you are unsure at all then call a qualified electrician. From what I have read you do have some improper conceptions and an electrician may be in order, no insult intended.

I am a Master electrician licensed in my state. For further questions or clarifications please reply here. One last piece of advice, go slow and draw a picture of what you are doing or trying to do so you can actually see it, especially at that adapter deal.

I guess I should say that I shall not be held responsible for any damages or injuries. These are lethal voltages.

Take care, Thor

Reply to
Thor

Neutral is not used for 220 volts. Make sure you wired the conversion cord so that both prongs of the 110 socket are connected to both hots on the 220 plug (one to each). Ground on the 110 outlet should be connected to the ground pin on the 220 plug. There is no neutral connection.

Gary

Reply to
Gary Coffman

Try holding the torch straight.

That symptom indicates it isn't getting 240 volts. Are you sure you wired the conversion cord correctly?

Gary

Reply to
Gary Coffman

I want to add a point about ground vs neutral. Since neutral normally carries current and ground should never, a voltage measurement between the two often shows a difference in potential, usually only 1 volt or so. You can be killed touching neutral in a circuit drawing load while you are "grounded". What is mentioned here is for series outlets but never assume safety by a color, etc. Circuits on long runs can cause similar problems although not usually the case in residential applications.

Your machine may be smart enough to know that there is voltage sitting on what it expects to be ground. Some circuit boards are very sensitive to "floating" grounds.

Reply to
Zorro

thank you guys for all the replys, great info , very educational. try to reply to all of your gretly appriciated replys

thans Gary, i did hold it straight , and it did cut crocked, now I hold it slightly tilted to the side and it cuts straigt, (I am using a non-conductive torch guide ) when torch tip replacement comes , i hope this will go away.

yes sir , it can not be done incorrectly with out tripping the circuit breaker.

110 socket has 3 screws 220 plug has 3 screws. i am using 3 wires all shielded 10 gauge, a foot in lenght

these symbols \ / | will represent the way the 220 plug looks like

from the 220 V plug \ (hot blade) black wire goes to 110 socket copper colored screws from 220 V plug / (hot blade) red wire goes to 110 socket silver colored screw from the 220 V plug (groung ) white wire goes to green terminal on the 110 socket.

there is no other screws if it would be done in any other way a breaker would trip ot wire would melt

the 110 V socket is clearly marked with black permanent marker 220 V only so no one plugs a 110 plug in accidentally and has a sping loaded cover over it.

yes o n the 110 socket I got 248 v between the short and the long blade , and 124 V form any hot to the groung terminal .

i know this converting extention is good

incomming 220 v to sub fed panel must be good because the dryer , a

220 v compressor , and a millermatic 175 runs off of it.

have I missed some thing , I think i covered all

thanks again, please feel free to comment

Reply to
acrobat-ants

thank you for the info,

question

from the main fuse panel to the sub fed panel, I have 3 6 gauge shielded wire and a bare 10 gauge copper wire going. this circuit is protedted with a 50 amp circuit braker at the main panel

the plastic sub panel only has 3 main terminal

2 for hot (for each hot leg 124 V) and 1 to a bus bar (ground) this panel is used as 220 service panel if there is no place for the neutral, should the left disconnected?

thanks

Reply to
acrobat-ants

Yes, as long as you don't need 110V in that panel. Be sure it's capped so it can't short to anything.

As I said before, I'm not an electrician but I don't believe that ground and neutral should EVER be tied together except in your main panel where the power initially comes into your house.

Best Regards, Keith Marshall snipped-for-privacy@progressivelogic.com

"I'm not grown up enough to be so old!"

Reply to
Keith Marshall

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