Post by: DJJ on April 13, 2008, 09:43:23 AM
Post by: Nitrogen on April 13, 2008, 09:55:53 AM
And what amperage will your new device pull? Make sure the combined pull is handleable by the wiring and circuit breaker.
Oh, and check your wiring code.
Post by: Matthew Carberry on April 13, 2008, 10:15:07 AM
See, they have an investment in your home, if it burns, the property tax revenue will drop AND they'll have to actually provide the fire and rescue services you pay for.
As long as they can dictate that you build safely, the house will maintain or increase in value, taxes will continue to be paid and they won't have to put any wear and tear on their shiny fire trucks.
So stick it to the man, ignore the code.
(or do what Nitro recommends)
Post by: geronimotwo on April 13, 2008, 12:20:27 PM
what do you plan on using the outlets for?
Post by: Firethorn on April 13, 2008, 12:37:42 PM
what do you plan on using the outlets for?
As others have noted, this is the critical question. In the USA, a 240V receptacle is normally only installed for high wattage applications where a 120V circuit is no longer practical. You can push almost twice as many watts over a given cable gauge at 240V, after all.
So, normally speaking, whenever you see a 240V circuit it was designed and installed for a particular application, and the wiring sized for it. Thus, unless for some strange reason they oversized the circuit or you can guarantee that both appliances aren't going to be used at the same time, you'll probably end up running a new circuit.
For example, an electric water heater is normally set up for 30 amps - because in normal use it takes around 25. Same with an electric dryer. Both shouldn't exist on the same circuit unless you like breakers popping or you have some way to make sure the water heater and dryer don't operate simultaneously.
Post by: ilbob on April 13, 2008, 01:05:16 PM
Or do these have to be dedicated, one-receptacle circuits?
I do not recall that the code imposes a limit.Post by: 280plus on April 13, 2008, 01:12:17 PM
Post by: Firethorn on April 13, 2008, 02:17:53 PM
As long as the combined amp ratings of the receptacles does not exceed the main circuit branch, you are ok.
Actually, you can exceed the amp ratings of the main circuit branch, this is frequently done with 120V wall outlets, remember. Each outlet is rated at 15 or 20A, and you got loads of them. It's just that it's not anticipated that most will be used, or even used near their capacity.
Post by: ilbob on April 13, 2008, 02:34:52 PM
As long as the combined amp ratings of the receptacles does not exceed the main circuit branch, you are ok.
this is not even an issue.
Post by: DJJ on April 13, 2008, 03:01:08 PM
Post by: Matthew Carberry on April 13, 2008, 03:34:34 PM
Well, I've heard from other sources that it's a flat-out no, so it's back to the drawing board.
Other sources?
OTHER sources?
Why the heck are you going outside APS for advice?
The only reasonable explanation is that you think we don't know what we're talking about.
Post by: 280plus on April 13, 2008, 03:50:20 PM
As long as the combined amp ratings of the receptacles does not exceed the main circuit branch, you are ok.
this is not even an issue.
Post by: ilbob on April 13, 2008, 04:03:31 PM
As long as the combined amp ratings of the receptacles does not exceed the main circuit branch, you are ok.
this is not even an issue.
The OP asked if they had to be dedicated circuits. The rating of an outlet or the combined ratings of all the outlets on the circuit just is not an issue to that question.
There are a few cases where the code requires dedicated receptacles IIRC. I think electric ranges are one.
Post by: 280plus on April 13, 2008, 04:58:01 PM
Quote
The OP asked if they had to be dedicated circuits. The rating of an outlet or the combined ratings of all the outlets on the circuit just is not an issue to that question.
Ohhhh,,,gotcha!
Post by: never_retreat on April 13, 2008, 05:25:06 PM
If this is for non fixed in place loads (ie portable something) you can draw up to 80 percent of the over current device. If it is for a fixed in place load you can only draw 50 percent of the over current device(range with a cord). Although you have to abide by what the manufacture of the device lists for the over current device size, not the electric code. The amperage listing on a UL approved piece of equipment trumps the NEC.
Since i don't know what your trying to connect I'll give a short run down.
Two 240v 20A outlets in your workshop for tools OK
Connecting an ac unit to your electric dryer NO
Connecting the dryer to a range NO
Under certain circumstances you can connect a cook top and wall oven together.
Post by: DJJ on April 13, 2008, 06:07:44 PM
Post by: Gewehr98 on April 13, 2008, 06:08:07 PM
(Not saying I have or haven't done this...)
Post by: ilbob on April 13, 2008, 06:16:17 PM
I depends on you application.
If this is for non fixed in place loads (ie portable something) you can draw up to 80 percent of the over current device. If it is for a fixed in place load you can only draw 50 percent of the over current device(range with a cord). Although you have to abide by what the manufacture of the device lists for the over current device size, not the electric code. The amperage listing on a UL approved piece of equipment trumps the NEC.
Since i don't know what your trying to connect I'll give a short run down.
Two 240v 20A outlets in your workshop for tools OK
Connecting an ac unit to your electric dryer NO
Connecting the dryer to a range NO
Under certain circumstances you can connect a cook top and wall oven together.
I am not sure where the numbers you quoted came from but they are just plain wrong. If this is for non fixed in place loads (ie portable something) you can draw up to 80 percent of the over current device. If it is for a fixed in place load you can only draw 50 percent of the over current device(range with a cord). Although you have to abide by what the manufacture of the device lists for the over current device size, not the electric code. The amperage listing on a UL approved piece of equipment trumps the NEC.
Since i don't know what your trying to connect I'll give a short run down.
Two 240v 20A outlets in your workshop for tools OK
Connecting an ac unit to your electric dryer NO
Connecting the dryer to a range NO
Under certain circumstances you can connect a cook top and wall oven together.
Cord and plug connected loads are not part of the premises wiring so they are not covered by the NEC.
UL listing of a piece of equipment never trumps the NEC. In fact, it is extremely rare that the NEC has anything to do with a UL listing at all. The code does require that you follow the installation instructions that come with a listed device, but in no way is that "trumping" anything.
Post by: geronimotwo on April 14, 2008, 08:23:30 AM
Post by: Tallpine on April 14, 2008, 09:04:20 AM
Even then, it will only be a nuisance to trip the breaker - though keep in mind that breakers will eventually wear out if tripped too often. And we used to have an old house that you couldn't buy replacement breakers for except at an extremely high price, as the company was out of business.
Post by: Matthew Carberry on April 14, 2008, 10:46:24 AM
I don't see any problem unless both devices will be in use at the same time.
Even then, it will only be a nuisance to trip the breaker - though keep in mind that breakers will eventually wear out if tripped too often. And we used to have an old house that you couldn't buy replacement breakers for except at an extremely high price, as the company was out of business.
Even then, it will only be a nuisance to trip the breaker - though keep in mind that breakers will eventually wear out if tripped too often. And we used to have an old house that you couldn't buy replacement breakers for except at an extremely high price, as the company was out of business.
Putting in a new panel is fun though.
Post by: Firethorn on April 14, 2008, 10:56:21 AM
Putting in a new panel is fun though.
Been there, done that, wasn't too difficult.
The biggest fun I had was working with the live, unfused(until the power pole), utility line. I wrapped them up good before moving them.
Post by: Matthew Carberry on April 14, 2008, 11:02:23 AM
Post by: Firethorn on April 14, 2008, 11:25:09 AM
You didn't have a exterior meter with a shut off?
What can I say... It's legacy.
It's an old 60 amp service. If the power company shuts it off I'll have to update it before they'd turn it back on. Don't have the money for that at the moment.
When I started the house had a main fuse box, 2 sub fuse boxes, and a circuit breaker box.
One day I was having some wierd power issues, went down to the basement and found the main fuse box sparking. I had already obtained a new breaker box, just moved up my replacement plans by quite a bit. I replaced the other two fuse boxes with utility ones to extend the wires to the breaker box.
So I still have a 60 amp service, but at least it's all new breakers.
Post by: Matthew Carberry on April 14, 2008, 11:27:14 AM
What did you wrap it with?
Post by: Firethorn on April 14, 2008, 12:00:22 PM
What did you wrap it with?
Electric wrap. It's like electrical tape without the adhesive. Sticks to itself like that crinkle wrap that people sometimes use instead of ace bandages today.
I did one line at a time, not touching the lead, doing my best not to ground myself just in case. By only doing one line, I only had to really worry about 120V, not 240V as with both.
Post by: Tallpine on April 14, 2008, 04:17:47 PM
Then they spliced it back together (hot!). This while standing on the roof of my carport.
Post by: Matthew Carberry on April 14, 2008, 06:35:30 PM
When I had to fix the meter socket at our old house, the "switch" that power company used to turn off the service was a pair of bolt cutters.
Then they spliced it back together (hot!). This while standing on the roof of my carport.
Then they spliced it back together (hot!). This while standing on the roof of my carport.
Well yeah. They're professional union electricians.
They're the only ones professional enough to use bolt cutters... <ZAP>
Post by: Firethorn on April 14, 2008, 07:36:03 PM
When I had to fix the meter socket at our old house, the "switch" that power company used to turn off the service was a pair of bolt cutters.
Then they spliced it back together (hot!). This while standing on the roof of my carport.
Then they spliced it back together (hot!). This while standing on the roof of my carport.
I think I like my electrical wrap better...
Post by: cassandra and sara's daddy on April 15, 2008, 02:14:38 AM
Post by: Nick1911 on April 15, 2008, 05:45:48 AM
240v 9-ft South Bend lathe in garage, tied to 240v clothes dryer outlet on other side of garage wall?
(Not saying I have or haven't done this...)
(Not saying I have or haven't done this...)
Thanks Gewehr. Now I have precise-timekeeping AND Lathe envy.
(On a side note, how the heck did you move that thing into your garage? I moved my mill with an engine hoist, but I haven't figured out how to move a big, old, American lathe into a residential garage...)
Post by: ilbob on April 15, 2008, 11:19:09 AM
I don't get all freaked out by working near hot leads anymore (if I have to) but I don't know I'd want to try to unhook a main power cable.
What did you wrap it with?
You probably should get freaked out by working on live equipment. A fair number of electricians die every year from doing just that and presumably they know what they are doing.
What did you wrap it with?
Post by: Firethorn on April 15, 2008, 11:53:49 AM
You probably should get freaked out by working on live equipment. A fair number of electricians die every year from doing just that and presumably they know what they are doing.
I know about electricity, I actually have some training on the stuff. Just not a professional electrician.
What probably gets the electricians killed is complacancy. I was very attentive when I was moving those wires. Any other work I turn the bloody juice off for.
Post by: Leatherneck on April 15, 2008, 12:51:20 PM
The HVAC guys still have four 220V breakers to install, but all my wiring in the box is done. Just imagining myself slowly sparkling into oblivion, attached to that unfused 300+ Amp service gives me shudders. Fear transcends apprehension.
TC
Post by: Nick1911 on April 15, 2008, 12:58:58 PM
Live box freaks me out. And mine at the cottage just got the underground service today, says Leatherness. (She's spending the week at the river "to keep an eye on things" Uh, Huh.)
The HVAC guys still have four 220V breakers to install, but all my wiring in the box is done. Just imagining myself slowly sparkling into oblivion, attached to that unfused 300+ Amp service gives me shudders. Fear transcends apprehension.
TC
The HVAC guys still have four 220V breakers to install, but all my wiring in the box is done. Just imagining myself slowly sparkling into oblivion, attached to that unfused 300+ Amp service gives me shudders. Fear transcends apprehension.
TC
I'm sure it's fused somewhere
That said, the resistance of your body is probably low enough to make your blood boil, but still far too high to trip a breaker at a substation.
Post by: Azrael256 on April 15, 2008, 01:10:42 PM
Quote
What probably gets the electricians killed is complacancy.
Yup. I had to coordinate quite a bit of electrical work at a previous job. All the electricians told me that almost every shock they had received came from not checking every wire every time. That, and coworkers playing pranks. Evidently 120 is funny to electricians.Rule #1 - Always treat the wire as loade... er... live, until you have inspected it for ammu... er... current.
Post by: AmbulanceDriver on April 15, 2008, 01:52:20 PM
We get there, and most of the work was already done. Just needed some old conduit cut out for where it was gonna go in the new locations. I asked him 3 times if the breakers were all off. "Oh yeah. Everythings off."
So he hands me a hacksaw and I start to saw on this one conduit. I get about three quarters of the way through when "BANG!" flash of light in the conduit, and the hacksaw blade now has a chunk missing out of it.
I look at him. Show him the hacksaw. "Everything's off, huh?
"He's lucky I didn't chase after him with that hacksaw......
Post by: 280plus on April 15, 2008, 02:07:18 PM
Post by: cassandra and sara's daddy on April 15, 2008, 02:08:04 PM
Post by: Matthew Carberry on April 15, 2008, 07:01:23 PM
I don't get all freaked out by working near hot leads anymore (if I have to) but I don't know I'd want to try to unhook a main power cable.
What did you wrap it with?
You probably should get freaked out by working on live equipment. A fair number of electricians die every year from doing just that and presumably they know what they are doing.What did you wrap it with?
Like explosives, if you are fearful as opposed to cautious, they'll bite you.
Post by: 280plus on April 16, 2008, 03:41:20 AM
Quote
Can you wire a second 240V receptacle into an existing 240V circuit?
Yes, but only by the light of the moon on the fifth of June.
Post by: Firethorn on April 16, 2008, 06:16:29 AM
So he hands me a hacksaw and I start to saw on this one conduit. I get about three quarters of the way through when "BANG!" flash of light in the conduit, and the hacksaw blade now has a chunk missing out of it.
As a teen I was moving into my new bedroom, that the previous owner of the house had slopped paint all over the outlets. Obvious fire hazard, so I get mom to get me the necessary replacement outlets and covers (less than $6, not a big deal).
I flip the breaker off, tell mom I'm changing the outlets.
I'm working on the second outlet, turning the screwdriver. Have a nice grip on the outlet with the neutral and ground connected, working on the hot. Mom goes into the utility room to do some laundry, sees the flipped breaker and flips it on. Fortuantly when I twitched from the electricity I prompty shorted the outlet back out with the screwdriver.
Then sat there for a minute or two before yelling at mom.
Lockout/Tagout is there for a reason!
Post by: Matthew Carberry on April 16, 2008, 07:54:59 PM
Live box freaks me out. And mine at the cottage just got the underground service today, says Leatherness. (She's spending the week at the river "to keep an eye on things" Uh, Huh.)
The HVAC guys still have four 220V breakers to install, but all my wiring in the box is done. Just imagining myself slowly sparkling into oblivion, attached to that unfused 300+ Amp service gives me shudders. Fear transcends apprehension.
TC
The HVAC guys still have four 220V breakers to install, but all my wiring in the box is done. Just imagining myself slowly sparkling into oblivion, attached to that unfused 300+ Amp service gives me shudders. Fear transcends apprehension.
TC
I'm sure it's fused somewhere
That said, the resistance of your body is probably low enough to make your blood boil, but still far too high to trip a breaker at a substation.
Hey, those big substation fuses are expensive. It's all a cost/benefit thing.