I recently bought a used arc welder that runs on 230V AC, 60Hz, single
phase. It did not come with a male plug, so I purchased one (see
). Unfortunately, the
diameter of the power cord on the welder is too small to be clamped
down by the male plug (see
). Also, the female outlet
I was hoping to use requires 4 prongs (see
). Can I buy a 4 prong male
plug and use it in this female outlet? If so, how would I wire it to
the welder's power cord? Why is the power cord on the welder so thin
compared with other heavy appliances in my home such as the dryer cable?
It looks like you have one of the newer 4-prong 220-240V single-phase
receptacles, and an older 3-prong plug. The 4-prong ones include a
neutral, so if you have an electric dryer or stove which also requires
120V for its control circuitry it's available via one hot leg and the
neutral. You should be able to buy one of the 4-prong plugs at any
hardware store. Wire the two hots and the ground terminals but leave
the neutral terminal disconnected. If your existing receptacle is wired
correctly then the W (white/neutral) terminal is the one you'll leave empty.
How many amps does the welder draw at 230V (look at the nameplate near
the cord inlet)? That plug style is usually rated for 50A, but if your
welder draws a lot less (20A or so) then that would explain the smaller
wire. See if you can read the markings on the power cord to determine
what gauge the wire is; there's always a chance that someone rewired it
but used the wrong stuff. I like to open up the cover to double-check
where the wires go before connecting any piece of used equipment like a
welder or machine tool. You'll want to make sure that the hots and
ground all go to the right places, and that the transformer taps are
properly jumpered if it's configurable for multiple input voltages.
All the 14-gauge 3-conductor service cords I see listed are only rated
for 18A. Grant's point was that the cord is sized for 40% duty cycle
(40A times 40% = 16A average current). But the heat generated in the
cord is a function of the current squared, so if you put through double
the current you're creating 4 times the heat. That gives you 4 times as
much heat 40% of the time, and no heat 60% of the time, which is
equivalent to 1.6 times as much heat all the time. If it were me I'd
rewire it with at least a 10-gauge SOOW cord (30A, oil resistant,
If it were me...
I would hit the local home supply store's electrical aisle for a replacement
stove or dryer cord that fits the wall outlet. Both are at least 30 amp
rated and a lot better than what you have.
Hi, David. I have some suggestions and feedback for you.
First, take a moment away from your welder and learn to crop and resize your
digital photos to a more appropriate size so they don't take so long for others
to view. I have fast DSL and they still take an annoyingly long time.
I also own a small arc welder, and it came with a light-gage cord too. I
replaced the cord with 10SO3, which was easy to do. That is heavily insulated
with thick rubber, and your plug will fit to it. Should you want to keep your
existing power cord, I suggest stripping about an inch of insulation from any
large power cord, slitting it lengthwise and removing material until it will
wrap closely around your cord, acting like a rubber bushing to effectively
increase your insulation thickness so the strain relief on your plug will bear
on it. You can build up a cord with two such bushings if you needed to.
I'm guessing that is a dryer receptacle, L1, L2 are the 220V hot leads, another
terminal is neutral, and the L-shaped thing is ground. From either 220V leg to
neutral would be 110V nominal. If you have a dryer that uses a 4-prong plug to
fit this receptacle and you want to unplug it occasionally and plug in your
welder, then by all means find that plug and put it on your welder. Else just
buy a receptacle that fits your electrical box and plug, and install them.
They use light cords on small welders to save money, of course. Those welders
can only be used on a 40% or smaller duty cycle, so they're cutting corners on
the power cord. I replaced mine for cosmetic reasons, not technical ones. I just
find it looks much more like a welder with a power cord about 3/4" thick.
On 10 Oct 2005 13:28:37 -0700, firstname.lastname@example.org wrote:
Blink blink...a 220vt welder...at what 10 amps? Thats the smallest
power wire Ive ever seen on a welder.
Exactly what kind of welder is it?
"Pax Americana is a philosophy. Hardly an empire.
Making sure other people play nice and dont kill each other (and us)
off in job lots is hardly empire building, particularly when you give
them self determination under "play nice" rules.
Think of it as having your older brother knock the shit out of you
for torturing the cat." Gunner
Remove the metal strain relief, turn it around, then screw it together. I
had to do this with my spot welder.
The following may not make any sense, but I'll try anyway.
The clamp on your plug looks like this right now:
You want it to look like this:
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