Miller Dialarc

[Oldpath05]

It's the reason they normally get wired to either a shut off box or straight to the breaker.

In my case I wired straight to the breaker and shut off the breaker when done for the day.

My Airco 300 (Miller 330 abp) can pull over 100 amps.

We'll guess you're right, again. I spent another 2 hr last night looking for 100 amp outlet and plug for the Miller, starting to look like I'll have to go from breaker to welder with no outlet.
From breaker panel, the welder is 22' at straight line at/under the welding bench, but by the time I go up, over, down, over, I need around 38'. Not so bad if buying that miserable 100 amp aluminum wire, $1.75/ft, I'd rather use 40' of #3 or #2 copper, BUT at $7.50-$8.00/ft kinda knock the wind out of that sail, I've already gone way over my summer budget on buying this that and the other thing.

 

[Oldpath05]

"My Airco 300 (Miller 330 abp) can pull over 100 amps.")<<<<Ok this is another rabbit trail, but 200 amp entrance, 100 amp breaker, 100 amp cable to welder, set welding machine at 250 amps, see the conundrum here............, welding at 250+ amps but braker panel is 200 amps and and breaker is 100 amps........How is it possible to weld with more amps than the amps coming in? Charlie Brown wants to know.

 

[BukitCase]

"How is it possible to weld with more amps than the amps coming in?"

Because it isn't about amps, it's about WATTS - an older style welder is basically just a glorified TRANSFORMER - and transformers, minus a few percent loss because of efficiency, put out the same WATTS as they take in - if you look at the power lines coming to your house, the lines on the pole aren't welding cable sized EITHER - this is because those lines are typically carrying 49 THOUSAND volts, but only a few HUNDRED amps.That way, those power lines can supply HUNDREDS of houses, each of which might be drawing over 100 AMPS - but those amps are only at 230 VOLTS, not 49 THOUSAND -

IF you do the math, that 49 thousand volt line at (say) 200 amps, is carrying 49,000 TIMES 200 amps, or 9.8 MILLION watts - but that voltage goes thru a transformer (looks like a fair-sized oil barrel, usually up on a pole) - the primary winding of the transformer would be rated at full line voltage, but the transformer steps that voltage DOWN to the 230 volts your house uses. This lets the house draw as much amperage as the power line has TOTAL, but at a MUCH LOWER VOLTAGE.

Your house, for example, even if it's using the full 200 amps, is only doing it at 230 volts - multiply those values together and you get 46,000 WATTS (46 kilowatts) which is NOWHERE NEAR the 9.8 MILLION watts the power line may be carrying, so OTHER houses can still get THEIR power.

Welders - same thing - input volts = 230, amps = 100, means WATTS = 230 x 100 or 23 kilowatts - but welder's secondary winding (depending on weld amps setting) may have open circuit voltage of around 80 volts, which is ONE THIRD of the INPUT voltage - so it can put out THREE TIMES as many amps as it's INPUT because it's not AMPS doing the work, it's WATTS, and watts = amps x volts.

Hope that made some sense, there's actually quite a bit more to it than that (like there's actually another level of distribution by power companies, so your LOCAL power poles usually have more like 10,000 volts instead of 5 TIMES that) - but the PRINCIPLE remains the same... Steve

 

[MinnesotaDaveChalmers]

"My Airco 300 (Miller 330 abp) can pull over 100 amps.")<<<<Ok this is another rabbit trail, but 200 amp entrance, 100 amp breaker, 100 amp cable to welder, set welding machine at 250 amps, see the conundrum here............, welding at 250+ amps but braker panel is 200 amps and and breaker is 100 amps........How is it possible to weld with more amps than the amps coming in? Charlie Brown wants to know.

Example: my invertec v300 pro from its manual.

Input: 230 vac x 52 amps = 11,960 watts

Output: 35 vdc x 200 amps = 7,000 watts

Output is a lower than input due to waste and running the fan.

 

[Oldpath05]

Obviously I'm not chatting with people who just weld for a living. So if I'm understanding this incorrectly, if I set my welder at 250 welding amps, it's actually XXXXXX watts, will I be graded on this quiz............

 

[Oldpath05]

Another conundrum, an aluminum service entrance cable says rated for 600 volts, but how many amps is that good for, another cable says rated for 300 volts, but how many amps is that good for? The copper cable coming off my welder says 600 volts, how many amps is that good for, so kunfusing, let alone the # size the cable goes by and then I punch up a chart and that's not written for a low skill weldah to understand.

On this chart there's still nothing I see to tell how many amps will a 300 volt entrance cable or 600 volt cable will carry, maybe I just had tomuch lead paint growing up.
Ampacity Charts

 

[Fallon]

Insulation is rated for a given voltage. Above that in thoery it could arc through. Wire & cables will never be rated for amperage, they will be rated in gauge (size of the conductor). You have to know the use case & installation plan for a given wire (in conduit, in free air, etc.). Then look up the gauge for that insulation type & install scenario in an appropriate chart.

Amps * Volts = watts

10 amp on a 100 volt circuit = 1000 watts & will work fine over some pretty small wire
100 amps on a 10 volt circuit = the same 1000 watts. But would burn up household wiring.

A welder just transforms low(ish) amps & high volts into lower voltage & higher amps. That higher amperage will melt metal, both intended at the end of the electrode & unintended in the case of to small wiring.

There are constant current welders & constant voltage welders. Stick & Tig are CC, they vary the voltage to keep the amps as set. I believe MIG is constant voltage, it varies the amperage to keep the voltage steady. In either case, the wattage while welding will vary

The amp rating on welders is perfectly accurate, but it just occurs at a lower voltage.

As for being graded on the quiz... The penalty for failing the quiz is burning your house down & insurance not covering things because of unpermitted modifications to the structure that weren't to code. If you don't understand all of this really well, hire an electrician.

 

[MinnesotaDaveChalmers]

Obviously I'm not chatting with people who just weld for a living. So if I'm understanding this incorrectly, if I set my welder at 250 welding amps, it's actually XXXXXX watts, will I be graded on this quiz............

Yes mostly. And the watts is dependent on the welding voltage at those amps.
But technically you don't really need to know all that to weld

I weld part-time from my home shop and now mobile too. I teach math from 7th grade remedial through calculus, woodworking and welding - quiz on Monday

 

[PhysAssist]

Insulation is rated for a given voltage. Above that in thoery it could arc through. Wire & cables will never be rated for amperage, they will be rated in gauge (size of the conductor). You have to know the use case & installation plan for a given wire (in conduit, in free air, etc.). Then look up the gauge for that insulation type & install scenario in an appropriate chart.

Amps * Volts = watts

10 amp on a 100 volt circuit = 1000 watts & will work fine over some pretty small wire
100 amps on a 10 volt circuit = the same 1000 watts. But would burn up household wiring.

A welder just transforms low(ish) amps & high volts into lower voltage & higher amps. That higher amperage will melt metal, both intended at the end of the electrode & unintended in the case of to small wiring.

There are constant current welders & constant voltage welders. Stick & Tig are CC, they vary the voltage to keep the amps as set. I believe MIG is constant voltage, it varies the amperage to keep the voltage steady. In either case, the wattage while welding will vary

The amp rating on welders is perfectly accurate, but it just occurs at a lower voltage.

As for being graded on the quiz... The penalty for failing the quiz is burning your house down & insurance not covering things because of unpermitted modifications to the structure that weren't to code. If you don't understand all of this really well, hire an electrician.

That's why I hired one and made him get the correct permits for my electrical installation- so it's ALL covered and insured by his business [in case it is found to have been done incorrectly] and my homeowner's insurances.

Now I just need to get him to come back and make me a cable from my genny to the welding outlet so we can feed current back into the house for outages.

Yes we know that we have to shut off the incoming house mains first.

In fact, the genny key is kept on a hook on the breaker box door[in our basement] with a placard what says to shut it off before even thinking about turning on the genny- which is out in the barn in any case.

This is all just in case I'm not home when the power drops out.

Can anyone tell me what size [gauge] 25' cable we will need to transfer 30-50 amps at 220V & 110V into my house wiring to support my home electrical use in emergencies? [and can I use it as an extension cord for my 220VAC stick/buzz box welder? [to keep this on topic a little anyway...]

 

[Fallon]

That's why I hired one and made him get the correct permits for my electrical installation- so it's ALL covered and insured by his business [in case it is found to have been done incorrectly] and my homeowner's insurances.

Now I just need to get him to come back and make me a cable from my genny to the welding outlet so we can feed current back into the house for outages.

Yes we know that we have to shut off the incoming house mains first.

In fact, the genny key is kept on a hook on the breaker box door[in our basement] with a placard what says to shut it off before even thinking about turning on the genny- which is out in the barn in any case.

This is all just in case I'm not home when the power drops out.

Can anyone tell me what size [gauge] 25' cable we will need to transfer 30-50 amps at 220V & 110V into my house wiring to support my home electrical use in emergencies? [and can I use it as an extension cord for my 220VAC stick/buzz box welder? [to keep this on topic a little anyway...]

To be legal there needs to be a physical interlock. Some switch that makes it physically impossible to connect the generator & the grid at the same time.

My 9.8kw of solar is tied to the grid. But the inverter is designed for it as well as properly permitted. It synchronized frequency to the grid & shuts off if the grid ever goes down. Have a seperate on-off-on switch upstream to toggle between generator input & grid input.