elec question RE 220V outlets

[Inspector507]

Actually this is from the manufacturer of my welder, who sells a UL listed product.

<font color="blue"> Using the following instructions, have a qualified electrician connect
a receptacle (NEMA 6-50R Type) to the power lines at the fuse
box. Three #10 or larger copper wires are required if conduit is
used. For long cable runs over 100', #8 or larger wire in conduit
will be needed to prevent excessive voltage drops. Fuse the two hot
lines with 50 ampere super lag type fuses as shown in the following
diagram. The center contact in the receptacle is for the grounding
connection. A green wire in the input cable connects this contact
to the frame of the welder. This insures proper grounding of the
welder frame when the welder plug is inserted into the receptacle.
If a separate disconnect switch is used, it should have two poles for
the two hot lines and both should be fused for 50 amperes. </font>

 

[VA_Joe]

Very interesting - learn something new each day. Seems like a loophole ripe for abuse (i.e. plugging an oven into an outlet meant for a welder). Thanks for the correction.

 

[sparkkky]

By the NEC you can not install a breaker that is rated at more amps than the wire!

Some electricans installed 40A breaker on 30A wire because of the start up load for A/Cs and the NEC put a stop to that along time ago.

Insp. I am surprised at you!

 

[mudcat]

SPARKKKY? /forums/images/graemlins/confused.gif You don't read the code book. Do you? /forums/images/graemlins/shocked.gif110.3.B /forums/images/graemlins/cool.gif

 

[Inspector507]

Joe,
A NEMA 6-50R outlet will not accept a range plug. That would take a NEMA 10-50R or a 14-50R outlet.

 

[VA_Joe]

All that I am saying is that if person A installs an outlet for one purpose according to one set of assumptions (i.e. for welder) and person B (a new owner, renter, etc) decides to use it for something totally different - I can envision the possibility of something very bad happening.

In the case of an HVAC circuit - the reason they allowed leeway is because the compressors are hardwired (i.e. no possibility for confusion) and breakers are not as tolerable to surges as fuses.

In any event - I think Mark got more advice than he ever envisioned /forums/images/graemlins/grin.gif.

Joe

 

[Inspector507]

<font color="blue"> In any event - I think Mark got more advice than he ever envisioned </font>

I'm sure he did /forums/images/graemlins/grin.gif

When I do inspections, I can't "expect" I have to inspect. But I do have to look at the current application/installation and approve it or not, according to the currently accepted version of the NEC®.

 

[sparkkky]

Under 110.3B unless Marks welder comes with any instructions included in the listing or labeling like Inspectors did, he could then be against code.

Looks like 630.12B pretty much covers it.

I will still run dedicated 50A circuits to any welders I wire, including my own.

 

[skid mark]

Thanks much for all of the great info fellas! I'm not 100% sure what I'll do yet, but I have a little time before I need to decide for sure.

I do have a big honkin "extension cord" as was mentioned. It's made of 2/0 cable that the utility company uses for overhead service entrance. The downside of it is that is is about 200 feet long and the length, combined with the heavy wire make it pretty bulky. But I don't want to cut it up as I have used it to reach things quite aways from the shop/garage. My neighbor has one that is 300 feet (they were cut from the same 500 ft roll). I've plugged one into the other a time or two to do some welding at a distant barn!

I got a chuckle out of the comment about some dummy plugging a stove into a welder outlet (or was it the other way around). GUILTY AS CHARGED!

Am I the only one who's first 220V welder was powered off of a dryer outlet? That's what I did for years. In my defense, this practice was suggested in a welding book I bought back when by Richard Finch and Tom Monroe.

Here's a new question for you:

How many amps are required by elec furnaces? I'm thinking of going that route for the "office" I'm going to finish off in the shop (want to keep all flamables (propane) out of the shop). A book I have said to plan on 20,000VA for an elec furnace. Yikes, that's like 90 amps! That will sure eat into my ever shrinking 200A service. Does that use a single 220V circuit or two separate smaller ones? I haven't owned a home with elec heat for years but if I remember right when I checked some fuses in a elec furnace in our first home years ago, there were four of them, not two.

Are there smaller furnaces that would be closer to 10,000VA? I'm only going to heat about 900 sq ft and it will be VERY well insulated.

I should have done my homework earlier. I'm learning that simply going and buying the "best and biggest" at the local box store isn't necessarily a great idea. It's starting to look like what they sell is generally simply the cheapest stuff available, fit for a small rent house. =(

Thanks again!

Mark

 

[VA_Joe]

I have been using propane in my shop because of its efficiency and (comparable) lower cost. In a garage/shop - what you really need is to have enough heating capacity to bring the temp up to a minimum of 50 degrees on a cold day. Bringing the temp up to 50 or so lets you work with a light jacket and without gloves (and have full hand/finger mobility). If the garage/shop is well insulated - the size of a system to meet these needs will be much smaller than that required to heat it to 70-80 degrees.

Also - because of the operating costs - I would take a second look at propane. The only time I would worry about propane (or natural gas) is if you were doing a wood shop work that generated a lot of fine saw dust (air and fine saw dust is an explosive combination). If you are only doing this work occasionally - then the easy way to avoid problems is to turn off the propane until the dust collector/vacuum catches up to the task

BTW - as long as the wire, circuit breaker, and outlet are correctly matched - there is nothing wrong with plugging a stove or dryer or welder or compressor into any outlet of your garage/shop. The point in the earlier discussion with Inspector is that it might be a good idea to check before plugging in (personally - for outlets - I always make sure that the three match as the potential savings is not worth the risk of a very bad mishap).

Joe

 

[GaryBDavis]

DTCOOPER,

Can you give me more information about the Polaris connectors and where I can get them? I have dual 50 amp outlets (for the welder and plasma cutter) on a single feed where I branch spliced 6AWG wire in a separate box just above my outlets. I used splice connectors covered with very thick grade heat shrink, but these Polaris connectors sound pretty cool. I'm interested in 8 through 4AWG sizes.

BTW, I'm in the Dallas area.

Thanks.

 

[Farwell]

I heat a portion of my small barn with a 2000 watt infrared tube wall heater without a fan. The room is 18'x18' and is very well insulated. This is where I do most of my wood work. I usually warm the room up about a 1/2 hour before I go to work. I also have a couple of 150 watt reflector bulbs over my equipment areas and this adds to the warmth. Living in Mid-Michigan in the Winter time gets mighty cold at times and the only problem I have with my heating system is the metal does not really get warm enough to keep in your hand for any length of time with out causing your fingers to get a little numb. My pole barn is heated with natural gas and has a 10 foot ceiling and I heat it with a 75,000 BTU Hot Dawg ceiling mount heater. I keep this at 47 degrees 24 hours a day during the cold weather. The metal still hurts my hands when I touch it. From all that I have read and heard, with the heater being that high off of the ground it is safe from fuel fumes but I am not sure about other flammable liquids so I use them in a non heated area if I need to use them.

 

[Farwell]

Something I forgot, is your monthly electric bill. It will probably be quite a bit higher with electric over most other heating alternatives.
Farwell