I've never welded anything before but always had the interest to
tinker around with metal building stuff so I finally bought a MIG
welder yesterday. Through various friends' input who work in the
sheet metal industry and research on the web I decided on a new
millermatic 175 that I got at local welding supply store for $625.

I still have to wire in my outlet for it and was reading the owner's
manual. It says the input voltage is 230, input amps at rated output
is 20, Max recommended circuit breaker in amperes is 20, Minimum input
conductor size in AWG is 14, minimum grounding conductor in AWG is 12.

I'm not an electrician but I have wired up my electrical box in my
garage but doesn't a 20 amp breaker on a welder seem low? The outlet
is a 50 amp outlet and I had planned on running 4AWG wire to it with a
50 amp double pole circuit breaker switch. Can this still be used
without doing any damage to the welder?

Also, the 4AWG wire I have is solid copper instead of stranded. Is
one better than the other?

"Mark" wrote in message
om...
I've never welded anything before but always had the interest to
tinker around with metal building stuff so I finally bought a MIG
welder yesterday. Through various friends' input who work in the
sheet metal industry and research on the web I decided on a new
millermatic 175 that I got at local welding supply store for $625.

I still have to wire in my outlet for it and was reading the owner's
manual. It says the input voltage is 230, input amps at rated output
is 20, Max recommended circuit breaker in amperes is 20, Minimum input
conductor size in AWG is 14, minimum grounding conductor in AWG is 12.

I'm not an electrician but I have wired up my electrical box in my
garage but doesn't a 20 amp breaker on a welder seem low? The outlet
is a 50 amp outlet and I had planned on running 4AWG wire to it with a
50 amp double pole circuit breaker switch. Can this still be used
without doing any damage to the welder?

Also, the 4AWG wire I have is solid copper instead of stranded. Is
one better than the other?

Wire it up to a circuit breaker and go. Your wiring is adequate. The
welder will only pull amperage when it is welding, aside from the small draw
for the fan motor.

If you were to weld a piece that is 20 feet long, it would heat up, but you
will be doing intermittent welds with a wirefeed with pauses inbetween, and
you will not even approach popping a breaker.

Yes, it is a welder, but you are welding in a much lower amperage rating
than if you were burning heavy rods. The machine is a 230v. machine, but
you will rarely be welding full throttle, and mostly it will be in the lower
ranges where the amp draw is waaaay under your breaker rating. If you need
to weld anything thick and turn it way up and run it for a long time, you
would be better to do it with rod instead because of cold lap and lack of
fusion in the weld.

HTH. Try sci.engr.joining.welding for additional information and help as
you progress on your learning curve. Lots of helpful guys and gals there,
too.

Steve

Plug it into your 50A outlet and weld. Nothing bad will happen.
The 50A breaker is there to protect your house from overcurrent
heating and resultant fire. Your little MIG welder won't even
warm up 4 gage wire a touch.

Copper, solid, stranded, no big deal. Stranded is easier to pull
and (sometimes) to connect, that's all.

Grant Erwin

Mark wrote:

I've never welded anything before but always had the interest to
tinker around with metal building stuff so I finally bought a MIG
welder yesterday. Through various friends' input who work in the
sheet metal industry and research on the web I decided on a new
millermatic 175 that I got at local welding supply store for $625.

I still have to wire in my outlet for it and was reading the owner's
manual. It says the input voltage is 230, input amps at rated output
is 20, Max recommended circuit breaker in amperes is 20, Minimum input
conductor size in AWG is 14, minimum grounding conductor in AWG is 12.

I'm not an electrician but I have wired up my electrical box in my
garage but doesn't a 20 amp breaker on a welder seem low? The outlet
is a 50 amp outlet and I had planned on running 4AWG wire to it with a
50 amp double pole circuit breaker switch. Can this still be used
without doing any damage to the welder?

Also, the 4AWG wire I have is solid copper instead of stranded. Is
one better than the other?

The 20 amp fuse on the 230V line gives you 4600 watts of power from the
outlet... but you are only welding at perhaps 25 to 30 volts, so you'll have
4600 watts / 25 volts = 184 amps of output (theoretically) less whatever is
lost in efficiency.
David




"Mark" wrote in message
om...
I've never welded anything before but always had the interest to
tinker around with metal building stuff so I finally bought a MIG
welder yesterday. Through various friends' input who work in the
sheet metal industry and research on the web I decided on a new
millermatic 175 that I got at local welding supply store for $625.

I still have to wire in my outlet for it and was reading the owner's
manual. It says the input voltage is 230, input amps at rated output
is 20, Max recommended circuit breaker in amperes is 20, Minimum input
conductor size in AWG is 14, minimum grounding conductor in AWG is 12.

I'm not an electrician but I have wired up my electrical box in my
garage but doesn't a 20 amp breaker on a welder seem low? The outlet
is a 50 amp outlet and I had planned on running 4AWG wire to it with a
50 amp double pole circuit breaker switch. Can this still be used
without doing any damage to the welder?

Also, the 4AWG wire I have is solid copper instead of stranded. Is
one better than the other?

Hello David,

Your math, while correct, only applies to purely resistive loads, and does not
apply to a highly inductive transformer device like a welder. What happens is
that the voltage and current get out of phase, (called power factor) so you can
have much higher current draw on the input of the welder versus the power output
of the welder.

Furthermore, there is an issue with an oversized breaker. Could be a fire risk
plugging it into an oversized breaker. You should put a 20 amp breaker feeding
the outlet for the welder.

Jeff

David Courtney wrote:

The 20 amp fuse on the 230V line gives you 4600 watts of power from the
outlet... but you are only welding at perhaps 25 to 30 volts, so you'll have
4600 watts / 25 volts = 184 amps of output (theoretically) less whatever is
lost in efficiency.
David

"Mark" wrote in message
om...
I've never welded anything before but always had the interest to
tinker around with metal building stuff so I finally bought a MIG
welder yesterday. Through various friends' input who work in the
sheet metal industry and research on the web I decided on a new
millermatic 175 that I got at local welding supply store for $625.

I still have to wire in my outlet for it and was reading the owner's
manual. It says the input voltage is 230, input amps at rated output
is 20, Max recommended circuit breaker in amperes is 20, Minimum input
conductor size in AWG is 14, minimum grounding conductor in AWG is 12.

I'm not an electrician but I have wired up my electrical box in my
garage but doesn't a 20 amp breaker on a welder seem low? The outlet
is a 50 amp outlet and I had planned on running 4AWG wire to it with a
50 amp double pole circuit breaker switch. Can this still be used
without doing any damage to the welder?

Also, the 4AWG wire I have is solid copper instead of stranded. Is
one better than the other?

A twenty amp circuit is big enough for your welder. In fact a 15 amp
circuit
( 14 awg wire and I assume they would have you use a 15 amp breaker
with 14 AWG wire ) will work because you will not be welding for long
periods of time. So you can use a smaller circuit for welding. But
putting in a 50 amp circuit is a good idea as you may run across a
stick welder at a good price sometime.

Just as you can plug in an alarm clock in a 20 amp circuit, you can
use your welder on a circuit that can supply lots more current. If
you want to protect the welder as well as the wire in the house, you
could either put a 20 amp breaker on that circuit until you need more
current for something. Or you can put a sub panel in the garage and
put a twenty amp breaker there.

I have a sixty amp circuit that goes to a plug next to the basement
door. I plug my 175 mig welder into it. I use the same circuit for a
stick welder.

Dan




(Mark) wrote in message
I still have to wire in my outlet for it and was reading the owner's
manual. It says the input voltage is 230, input amps at rated output
is 20, Max recommended circuit breaker in amperes is 20, Minimum input
conductor size in AWG is 14, minimum grounding conductor in AWG is 12.

I'm not an electrician but I have wired up my electrical box in my
garage but doesn't a 20 amp breaker on a welder seem low? The outlet
is a 50 amp outlet and I had planned on running 4AWG wire to it with a
50 amp double pole circuit breaker switch. Can this still be used
without doing any damage to the welder?

Also, the 4AWG wire I have is solid copper instead of stranded. Is
one better than the other?

That will be just fine.

THey just don't want to hear about using zip cords so they give min.'s
:-)

Martin
--
Martin Eastburn, Barbara Eastburn
@ home at Lion's Lair with our computer
NRA LOH, NRA Life
NRA Second Amendment Task Force Charter Founder

On 7 Nov 2003 08:35:13 -0800, (Mark) wrote:
I still have to wire in my outlet for it and was reading the owner's
manual. It says the input voltage is 230, input amps at rated output
is 20, Max recommended circuit breaker in amperes is 20, Minimum input
conductor size in AWG is 14, minimum grounding conductor in AWG is 12.

I'm not an electrician but I have wired up my electrical box in my
garage but doesn't a 20 amp breaker on a welder seem low? The outlet
is a 50 amp outlet and I had planned on running 4AWG wire to it with a
50 amp double pole circuit breaker switch. Can this still be used
without doing any damage to the welder?

Yes. According to Code, the service panel breaker must be sized to
protect the premises *wiring*, not the load. With #4 wire, a 50 amp
breaker meets that criteria.

If Miller wants the load protected (and UL acceptance), they have
to install their own fuse or circuit breaker *in the unit*. In fact they
have, it has a 25 amp breaker, CB1, in its primary circuit. So don't
worry about hurting it by plugging it into a heavier circuit.

Also, the 4AWG wire I have is solid copper instead of stranded. Is
one better than the other?

Solid is better for the terminations used for circuit breakers
and outlets. Stranded really should only be used with terminals
designed for use with stranded wire (full crimp preferred).

Gary

On Fri, 07 Nov 2003 19:52:48 -0800, Jeff wrote:
Hello David,

Your math, while correct, only applies to purely resistive loads, and does not
apply to a highly inductive transformer device like a welder. What happens is
that the voltage and current get out of phase, (called power factor) so you can
have much higher current draw on the input of the welder versus the power output
of the welder.

Correct, which is why you want to use a heavier wire and a heavier
service breaker than would be needed for a purely resistive load.

Furthermore, there is an issue with an oversized breaker. Could be a fire risk
plugging it into an oversized breaker. You should put a 20 amp breaker feeding
the outlet for the welder.

If he's using #4 wire, a 50 amp breaker is not oversize. It will trip before
the wire overheats dangerously. That's what Code says it must do. What
it *won't* do is nuisance trip with the reactive load provided by the welder.

The welder has its own internal breaker, CB1, a 25 amp delay breaker,
which is designed to protect the welder in case of a welder fault.
Because it is a delay breaker, it won't nuisance trip like a 20 amp
service panel breaker would.

Gary

Gary Coffman wrote:

Solid is better for the terminations used for circuit breakers
and outlets. Stranded really should only be used with terminals
designed for use with stranded wire (full crimp preferred).

Gary

Gary, how many service entrance pannels have you wired? All the
breakers I've wired for ampacities greater than 30 A have had
terminals suitable for stranded wire. ie. a hole with a screw
to pinch the wire against the opposite side.
...lew...

In article , Lewis Hartswick wrote:
Gary Coffman wrote:

Solid is better for the terminations used for circuit breakers
and outlets. Stranded really should only be used with terminals
designed for use with stranded wire (full crimp preferred).
Gary

Gary, how many service entrance pannels have you wired? All the
breakers I've wired for ampacities greater than 30 A have had
terminals suitable for stranded wire. ie. a hole with a screw
to pinch the wire against the opposite side. ...lew...

i was thinking that #4 solid would be hard to work with. --Loren

In article , Gary Coffman wrote:
On 7 Nov 2003 08:35:13 -0800, (Mark) wrote:
....
I'm not an electrician but I have wired up my electrical box in my
garage but doesn't a 20 amp breaker on a welder seem low? The outlet
is a 50 amp outlet and I had planned on running 4AWG wire to it with a
50 amp double pole circuit breaker switch. Can this still be used
without doing any damage to the welder?

Yes. According to Code, the service panel breaker must be sized to
protect the premises *wiring*, not the load. With #4 wire, a 50 amp
breaker meets that criteria.
....
Also, the 4AWG wire I have is solid copper instead of stranded. Is
one better than the other?

Solid is better for the terminations used for circuit breakers
and outlets. Stranded really should only be used with terminals
designed for use with stranded wire (full crimp preferred). Gary

there are terminations for stranded wire, used by electrical
contractors. they look like just a barrel, they are crimped
on. code used to allow use of solder, too.

a co-worker almost got fired from GE when he connected main
power to a computer with stranded wire at a test station and
got a strand shorted. they had frayed out and were a bit
difficult to insert. they said he should have known that
the wires s/b crimped or solderd. no one else seemed to know.

--Loren

On Sat, 08 Nov 2003 14:13:39 GMT, Lewis Hartswick wrote:
Gary Coffman wrote:

Solid is better for the terminations used for circuit breakers
and outlets. Stranded really should only be used with terminals
designed for use with stranded wire (full crimp preferred).

Gary

Gary, how many service entrance pannels have you wired?

Probably well over 1,000 over the years.

All the
breakers I've wired for ampacities greater than 30 A have had
terminals suitable for stranded wire. ie. a hole with a screw
to pinch the wire against the opposite side.

Unless the hole is a snug fit to the wire to prevent the strands
from spreading when loaded by the screw, which it usually isn't,
that won't give a good full ampacity connection. When I have to
attach stranded cable to a breaker, I use a proper size crimp
ferrule over the wire first. Stranded wire needs a full 360 degree
compression to achieve a proper connection.

Gary

DO NOT SOLDER standed wire and then use any sort of pressure clamp to
attach the wire. The solder will cold flow and you will then have a
loose connection.
The loose connection will oxidize and then overheat. Where I used to
work they did an inspection to make sure that no plugs had stranded
wire that had been soldered. They missed a couple of power cords, but
the problem showed up a year or so later.

Dan


Loren Coe wrote in message news:XS8rb.144752
there are terminations for stranded wire, used by electrical
contractors. they look like just a barrel, they are crimped
on. code used to allow use of solder, too.

a co-worker almost got fired from GE when he connected main
power to a computer with stranded wire at a test station and
got a strand shorted. they had frayed out and were a bit
difficult to insert. they said he should have known that
the wires s/b crimped or solderd. no one else seemed to know.

--Loren

In article , Dan Caster says...

DO NOT SOLDER standed wire and then use any sort of pressure clamp to
attach the wire. The solder will cold flow and you will then have a
loose connection.
The loose connection will oxidize and then overheat. Where I used to
work they did an inspection to make sure that no plugs had stranded
wire that had been soldered. They missed a couple of power cords, but
the problem showed up a year or so later.

One way around that is to crimp the connection, and then flow
solder into it afterwards. These don't loosen up after time.
It's a bit of a bodge and I would never wire any power connections
that way, but I've found that doing this for motorcycle wiring
has two advantages: 1) the solder will wick into the
stranded wire for a way, and prevent work-hardening and
fracture near the crimp connector, and 2) it prevents corrosion
at the crimp when the connector will be exposed to rough
environment.

Jim

==================================================
please reply to:
JRR(zero) at yktvmv (dot) vnet (dot) ibm (dot) com
==================================================

On 9 Nov 2003 15:32:26 -0800, (Dan Caster) wrote:
DO NOT SOLDER standed wire and then use any sort of pressure clamp to
attach the wire. The solder will cold flow and you will then have a
loose connection.
The loose connection will oxidize and then overheat. Where I used to
work they did an inspection to make sure that no plugs had stranded
wire that had been soldered. They missed a couple of power cords, but
the problem showed up a year or so later.

Exactly right. Solder is a no-no for any high ampacity connection.

Gary

On 9 Nov 2003 15:43:01 -0800, jim rozen
wrote:

In article , Dan Caster says...

DO NOT SOLDER standed wire and then use any sort of pressure clamp to
attach the wire. The solder will cold flow and you will then have a
loose connection.
The loose connection will oxidize and then overheat. Where I used to
work they did an inspection to make sure that no plugs had stranded
wire that had been soldered. They missed a couple of power cords, but
the problem showed up a year or so later.

One way around that is to crimp the connection, and then flow
solder into it afterwards. These don't loosen up after time.
It's a bit of a bodge and I would never wire any power connections
that way, but I've found that doing this for motorcycle wiring
has two advantages: 1) the solder will wick into the
stranded wire for a way, and prevent work-hardening and
fracture near the crimp connector, and 2) it prevents corrosion
at the crimp when the connector will be exposed to rough
environment.

Would silver solder be even better? The reason I ask is that I have
just silver soldered the crimps on a set of battery adapter cables for
second son's UPS. (The free 12V gel cells are too big to fit in the
case)
Gerry :-)}
London, Canada

Thanks everyone for your comments. Turns out I didn't have enough #4
wire to run 3 wires the distance I wanted the outlet at so I went next
door to help my neighbor who'd building a house now and we were
talking about it and I mentioned I needed to go and get some wire, he
handed me his leftover roll of #6-3 wire he used for his stove. I did
call Miller and confirmed that I should use a 20 amp breaker, they
also said a 30 would work too so that's what I used. I don't think in
my projects I'll ever need it all. Hooked it all up and welded up the
first thing ever last night, a small welding table. It was alot of
fun, doesn't look so pretty but that will take practice.

Thanks again,
Mark

I think that silver solder would be okay. Silver solder is much
harder and not likely to yield as soft solder does. Also it will not
oxidize easily as soft solder does.

Dan


Gerald Miller wrote in message


Would silver solder be even better? The reason I ask is that I have
just silver soldered the crimps on a set of battery adapter cables for
second son's UPS. (The free 12V gel cells are too big to fit in the
case)
Gerry :-)}
London, Canada

Gerald Miller wrote:

It's a bit of a bodge and I would never wire any power connections
that way, but I've found that doing this for motorcycle wiring
has two advantages: 1) the solder will wick into the
stranded wire for a way, and prevent work-hardening and
fracture near the crimp connector, and 2) it prevents corrosion
at the crimp when the connector will be exposed to rough
environment.

You might consider crimping the connection and then applying two layers
of heat shrink tubing. The first is the two layer stuff where the inner
layer melts while the outer layer shrinks. If you heat from the middle
toward the ends, this will give an excellent seal. The second is
regular flexible heat shrink somewhat longer than the first
application. The net result is a well sealed connection with a flex
relief somewhat like those tapered rubber ends mold on factory
connections.

Ted

On Sun, 09 Nov 2003 19:28:43 -0500, Gary Coffman wrote:

On 9 Nov 2003 15:32:26 -0800, (Dan Caster) wrote:
DO NOT SOLDER standed wire and then use any sort of pressure clamp to
attach the wire. The solder will cold flow and you will then have a
loose connection.
The loose connection will oxidize and then overheat. Where I used to
work they did an inspection to make sure that no plugs had stranded
wire that had been soldered. They missed a couple of power cords, but
the problem showed up a year or so later.

Exactly right. Solder is a no-no for any high ampacity connection.

Gary

Oddly enough, on bolted (1,000A...20,000) busbar connections, tinned ends are
preferred. The solder, being softer than the copper, deforms and allows more
area to contact. It also reduces oxidation. 'Course, it's bad juju if there's
any SO2 in the atmosphere.

Mark Rand (just stirring things)
RTFM