Another wiring question for the 187...

[wyomingclimber]

I'm trying to add this circuit to my garage and I'm not sure how much current I need.

I was going to run 6awg wire from a 50 amp/240v breaker to a NEMA 6-50R receptacle.

In looking through the manual, though, it says that the maximum recommended regular (i.e. not time delay) circuit breaker size is 30a and the minimum awg is 14.

So could someone tell me what I need here? It seems unusual to have a max circuit capacity and not a minimum one, as well as specing a minimum awg that can only handle 15 amps. But then, this is my first welder...

Thanks.

[84ZMike]

30 amp breaker and depending on how far a run you need.....number 12 / 10 on the wire (10 would be what I'd use)...... the 15 amps you are referring to with the 14 ga. is true under a full time load..... you HH187 isn't a full time load....good luck.
Mike

[Noisy Nova]

On the other hand, if you use a 50amp breaker and 6ga wire, you'll be in a position to accommodate a larger welder in the future.:D

[wyomingclimber]

On the other hand, if you use a 50amp breaker and 6ga wire, you'll be in a position to accommodate a larger welder in the future.:D

That's what I was thinking--a welder or some other ridiculously cool tool that costs the earth.

Stating a maximum 30a breaker, though, seems to imply that putting something beefier in could somehow cause damage to the 187 or be a safety issue...

[Jerel]

wyomingclimber,

I used #8 wire (#10 would have been large enough) and a 30 amp breaker on the circuit for my Hobart 187.
Look on page 15 and 16 of the Hobart 187 owner's manual to see what they recomend.
If you do not have a manual, then you can download one here.


http://www.hobartwelders.com/om/6digit/o228187a_hob.pdf

Jerel

[Broccoli1]

Should answer yer questions

http://www.hobartwelders.com/weldtalk/showthread.php?t=21460&highlight=220+wiring

:)

[wyomingclimber]

Should answer yer questions

http://www.hobartwelders.com/weldtalk/showthread.php?t=21460&highlight=220+wiring

:)

That's a great post--not sure how my search missed it. Thanks.

[MrUnix]

Stating a maximum 30a breaker, though, seems to imply that putting something beefier in could somehow cause damage to the 187 or be a safety issue...

You can run the welder off a 100 amp breaker if you wanted, it wouldn't hurt it a bit. The machine only draws what it needs. The breaker is there to protect the wire, not the machine. Just make sure you match the breaker size with the wire you use and you won't have to worry about burning down your house :)

PS: I almost always run 6/2 with a 50 amp breaker to a 6-50R. You never know what you might want to use that outlet for in the future.

Cheers,
Brad

[Broccoli1]

That's a great post--not sure how my search missed it. Thanks.

You probably searched 240v:)

I searched 220 and 240

[Zrexxer]

You can run the welder off a 100 amp breaker if you wanted, it wouldn't hurt it a bit. The machine only draws what it needs. The breaker is there to protect the wire, not the machine. THANK you. I don't know why that's such a hard concept to grasp but it's come up here over and over.

I tell people that if their theory were true and the load automatically draws the maximum value of whatever breaker it's connected to, then every light bulb in your house would immediately explode the instant it's turned on, because that 0.5A light bulb is plugged into at least a 15A circuit. :rolleyes:

[wyomingclimber]

THANK you. I don't know why that's such a hard concept to grasp but it's come up here over and over.

I tell people that if their theory were true and the load automatically draws the maximum value of whatever breaker it's connected to, then every light bulb in your house would immediately explode the instant it's turned on, because that 0.5A light bulb is plugged into at least a 15A circuit. :rolleyes:

This was exactly my thought.

The reason the question comes up is probably because the Hobart manual manual CLEARLY states a maximum breaker capacity of 25a. Why? I have no idea. Maybe they're assuming you're using their stated minimum awg of 14?

[Clay Walters]

THANK you. I don't know why that's such a hard concept to grasp but it's come up here over and over.

I tell people that if their theory were true and the load automatically draws the maximum value of whatever breaker it's connected to, then every light bulb in your house would immediately explode the instant it's turned on, because that 0.5A light bulb is plugged into at least a 15A circuit. :rolleyes:

It has come up here many times. When I made a similar statement because I believe the load center, breakers, wire requirements, grounding, etc. are to protect the building. (In my case, my home)

However I was promptly chastised and it was pointed out that the "maximum" breaker referenced in my welder manual was to protect the machine. The welder manufacturer doesn't concern themselves too much with your location I imagine. If I recall correctly this is to protect when something goes wrong and you want the breaker to pop before too much damage occurs to the welder.

For my own part I used 6ga wire to a 50amp recepticle. I started with a 50amp breaker but switched it out to a 30amp breaker when I purchased my HH187. Although I'm not certain I've read where 6ga wire can carry up to 60amp safely.

Regards,

Clay

[wyomingclimber]

It has come up here many times. When I made a similar statement because I believe the load center, breakers, wire requirements, grounding, etc. are to protect the building. (In my case, my home)

However I was promptly chastised and it was pointed out that the "maximum" breaker referenced in my welder manual was to protect the machine. The welder manufacturer doesn't concern themselves too much with your location I imagine. If I recall correctly this is to protect when something goes wrong and you want the breaker to pop before too much damage occurs to the welder.

For my own part I used 6ga wire to a 50amp recepticle. I started with a 50amp breaker but switched it out to a 30amp breaker when I purchased my HH187. Although I'm not certain I've read where 6ga wire can carry up to 60amp safely.

Regards,

Clay

Clay:

I've read two wiring books and scoured the internet regarding this question. As near as I can tell, Zrexxer is right. There would have to be a serious design flaw or some welder-specific issue that I can find no mention of to make it necessary for your home breaker to protect the machine.

In a cycling forum I used to participate in, knowlegable people wrote posts answering many FAQs and then pointed people to them. My vote would be for something like this:

The wiring instructions in the Hobart manual are confusing, misleading, and could result in the installation of a receptacle that does not meet code. Disregard them.

The minimum requirement for a dedicated receptacle is a NEMA 6-50R receptacle, 10/2 wire, and a 30a breaker. An optimal installation (which would allow for future upgrades) would involve 6/2 wire and a 50a breaker.

GFCI is not required unless you plan to plug a body of water into this outlet (i.e. pool, hot tub, etc.) GFCI could be used if desired, however, it could cause excessive sensitivity to current variations.

For all practical purposes, the footnote regarding matching time-current curves to a time delay fuse is mumbo-jumbo. Use the same brand breaker as your box.

Now if someone who actually knows what the heck they're talking about would just clean that up and post it, all problems will be solved :D

[Noisy Nova]

I use a range receptacle, 'cause I use an old stove for powder coating. Then I use a range pigtail with 50A welder receptacle.

http://i41.photobucket.com/albums/e251/noisynova/Garage%20stuff/DSCF0648.jpg

[hankj]

Welder manuals pretty much all have a disclaimer in the wiring information that references the National Electrical Code.

The pertinent sections are Art 310, Table 16 for wiring sizes, and Art. 630 for welder-specific wirng, such as duty cycle de-rating tables.

Briefly, any electrical outlet wired per the code needs to be constructed to handle 125% of the rated load. Following that logic, a 15-amp lighting circuit must actually be built to handle 18.75 amps real-time load (15 x 1.25), hence a #14 size copper wire with 90° rated insulation is required. These requirements are based on the assumption that anything connected to the branch circuit may need to operate 100% of the time.

Circuits suppying equipment that has a duty cycle (will not draw a load 100% of the time) can be constructed with lesser materials, depending on the duty cycle. Welders are covered in Art. 630 of the NEC. Table 630.11 (A) provides the reduction factors permitted in wire sizes for arc welders. There are specific articles for other appliances like motors, etc.

My personal apprach has always been that, in a residential setting, any circuit should be built to the 125% standard. This covers the "next guy" who buys your house and tries to run his 50-amp space heater from your 30-amp welder circuit that was built to Art. 630 standard!

If you are going to build a circuit in your garage at a lesser rating than 125% of rated load, [B]then make sure it is well labeled[B]!

Hank

[Sberry]

Something else to consider at least in theory and actually a code issue is that,,,, there is a legal limit to the breaker to this machine and that is 50A. The breaker is there to some extent to protect the machine or more importantly the operator, it needs to provide short circuit interruption for the internals of the machine and the cord is a number 12,,, limited to 50A circuits. If it had a 10 cord it could go to 60A and an 8 for 100A.