House power: amps and fuses

[Don Davis]

Hey gang,

 

Quick question on using house power on location. Most residential locations have 15 and 20 amp fuses. If I need more amps out of a circuit, can I simply replace a 20 amp house fuse with a 30 amp fuse? Say I need to run a 2K and a 1K off of one cicuit. Surely it's not that simple...

 

Don Davis

Novice DP

Los Angeles

[Laurent Andrieux]

No, you certainly not do that. You can use an "open" wire at one end, that you plug on the main house feed. The thing is I'm sorry my english vocabulary is too poor as to explain how to do it with the right words, so wait until some american gaffer explains is well, but don't ever plug more than the maximum admitted intensity on a circuit.

[David Mullen ASC]

No, you certainly not do that. You can use an "open" wire at one end, that you plug on the main house feed. The thing is I'm sorry my english vocabulary is too poor as to explain how to do it with the right words, so wait until some american gaffer explains is well, but don't ever plug more than the maximum admitted intensity on a circuit.

<{POST_SNAPBACK}>

 

I don't recommend any of that either. A trained and licenced electrician can do a "tie-in" to the main power coming into a building, before the breaker box, with the right equipment and permission -- but don't do it yourself because it's very dangerous and illegal to boot.

 

As for putting in a 20 amp breaker or fuse into something rated for 10 amps, that's how electrical fires get started. It's rated for 10 amps for a reason.

[Laurent Andrieux]

tie-in

 

Thanks, looks like it's the word I was missing...

[Patrick Neary]

a simpler solution is to get a "distro box" (not a stage box but just multiple edison outlets) that plugs into a stove or dryer plug. Then you have a nice bit of power to use, usually 30 or 40 amps, but make sure the box is set up for splitting the 220 into 2x 110. Most gaffers I know have made one of these at one time or another, and often times you can find them at your grip/lighting house. There are a number of different plug shapes/sizes, though, and finding the right connector is usually the hardest part of the equation...

[Laurent Andrieux]

Good idea ! Can't you find these kind of plugs in big departement stores ? In a specialized shop for house electrical stuff ?

[Patrick Neary]

yes! you can get everything to build your own box (except maybe the actual plug, which any appliance repair place should have) at Home Depot.

 

(or is it Chateau Depot over there?) :)

[Ed Nyankori]

As for putting in a 20 amp breaker or fuse into something rated for 10 amps, that's how electrical fires get started. It's rated for 10 amps for a reason.

<{POST_SNAPBACK}>

 

The breakers rating 20amps is set to protect the copper wire leaving the breakerbox. Therefore using a higher rated breaker definitely will keep the breaker from tripping but will not do what it is intended to do: protect the wire that provides the electricity to said outlet. Even if you dont cause a fire you'll damage the insulation in the 'wire'. Which may lead to a fire. Its also irresponsable and illegal.

[Rik Andino]

Hey how about a simple solution...

Rent a genny and run an outside line from it

To get the extra power--

It'll be easier & cheaper than hiring a CERTIFIED electrician to do a tie in.

 

& remember the key word here is certified

Any idiot calling himself an electrician can try to do it...

But I've seen some stupid and nasty accidents happen this way.

 

Be careful & Good Luck

[Nelson Rogers]

What PatrickNeary mentioned is your best bet. You need a Stove or Dryer Plug to Joy adapter. (It should split into 2 female joy plugs) and from this you can run lengths of joy to a "dief" aka 3x20 which has 3 20amp edison plugs. Make sure you check what the breaker is rated at..ie: if it is rated at 30amps, remember you only have 30amps available to you at each dief, which you can run two from the stove or dryer plug. So in total you can have 60amps of power split between the two diefs. I have done this many times on lower budget shows that can't afford a generator. I have managed to run a 4k HMI, 2500 and some 1200's all from using the power from stoves and dryers. It works great, and allows you to be able to use a bit bigger lights then you can with just normal house outlets. But like I said, make sure you check what the breakers are rated at, and tape up the extra outlets on the diefs if you can't run a full 60amps, just so that someone won't plug more into it then you have the power for. And when it comes to electricity, always always safety first! Good luck!

 

Nelson Rogers

[Laurent Andrieux]

Yep, but mind that the total amount of intensity is in the range of the total supplied powered, according to the customer's subscription... Usually, you can see how it is set by the counter... In France, you pay the lent for the maximum intensity avaible that maybe only 32 A for instance even though you have 2 32 A plugs in the house... 32 A is already a big amount in a flat or little house...

[Phil Rhodes]

Hi,

 

Over the last week I've been slightly shocked at how little power there is available in domestic circumstances in the US. We couldn't run up all of the systems we were working on in one room of an office, and that's only three fairly ordinary PCs, some monitors and disk arrays. Apparently there's only six amps available per room, and at 110V that's nothing!

 

Phil

[Ed Nyankori]

What PatrickNeary mentioned is your best bet. You need a Stove or Dryer Plug to Joy adapter. (It should split into 2 female joy plugs) and from this you can run lengths of joy to a "dief" aka 3x20 which has 3 20amp edison plugs. Make sure you check what the breaker is rated at..ie: if it is rated at 30amps, remember you only have 30amps available to you at each dief, which you can run two from the stove or dryer plug. So in total you can have 60amps of power split between the two diefs.  I have done this many times on lower budget shows that can't afford a generator. I have managed to run a 4k HMI, 2500 and some 1200's all from using the power from stoves and dryers. It works great, and allows you to be able to use a bit bigger lights then you can with just normal house outlets.  But like I said, make sure you check what the breakers are rated at, and tape up the extra outlets on the diefs if you can't run a full 60amps, just so that someone won't plug more into it then you have the power for. And when it comes to electricity, always always safety first! Good luck!

 

Nelson Rogers

<{POST_SNAPBACK}>

Ive often wondered about this practice. The problem is 220v stove outlets are fed by 10/3 that means 10 gauge wire(rated @30amps) 3wire (red,black & white). the red and the black each 'hot' at 110v and the white is common. So if you split up the red and black to give you two legs each 110v then you are still running both circuits off a single common wire. Given that the breaker only protects the hot wires you have a great potential for damaging that common wire.

 

I used to do electrical work on homes and was an electronics tech in the Navy. I have not reviewed the NEC (national electric code) since 1996; but Im pretty sure this practice is not allowed and in theory very dangerous (no common wire protection).

[Patrick Neary]

but you still only have 30A total to use, still within the capacity of the #10 wire, and still limited by the 220/30A breaker, correct?

 

Most stoves split 110 off of their incoming 220v to power the clock, light, receptacle, etc. I assume it's a similar idea (?)

 

As an aside, if you want to see fun with electricity in filmmaking, check this thread out (you'll have to scroll down a bit):

 

http://www.cinematography.com/forum2004/in...?showtopic=5479

 

I'd love to hear what an electrician thinks of that!

[Patrick Neary]

....or maybe a better example would be a typical split or multiwire-circuit? that's also using a common neutral.

[John Pytlak RIP]

In the USA, most jurisdictions and safety rules are based on the National Electrical Code:

 

http://www.mikeholt.com/bookitem.php?id=42...egory_from=Book

 

Doing it wrong can be a shockingly fatal experience. :(

[Patrick Neary]

Ive often wondered about this practice. The problem is 220v stove outlets are fed by 10/3 that means 10 gauge wire(rated @30amps) 3wire (red,black & white). the red and the black each 'hot' at 110v and the white is common. So if you split up the red and black to give you two legs each 110v then you are still running both circuits off a single common wire. Given that the breaker only protects the hot wires you have a great potential for damaging that common wire.

 

I used to do electrical work on homes and was an electronics tech in the Navy. I have not reviewed the NEC (national electric code) since 1996; but Im pretty sure this practice is not allowed and in theory very dangerous (no common wire protection).

<{POST_SNAPBACK}>

 

To clarify (or just correct) my earlier post, as I understand this kind of set-up, because each hot wire (from the 220 circuit) is out of phase with the other, the neutral will only carry the difference of the two new 110 branches. So if you have one of our dryer-plug adaptors splitting off into 2 110v boxes, and you have a 2k plugged into one side, and a 1k plugged into the other side, the neutral is actually only carrying 10 amps (rounded up). Or if you have a 2k plugged into one side, and nothing in the other, the neutral carries 20amps (rounded-up), or if you have a 2k in each side, then the neutral is actually, well, neutral.

 

so you do have 30 amps each side (60 total) to play with in a 220v/30a circuit. If you overload one side, one of the breakers (tied to the other) will trip and shut down both sides.

 

again, as i understand it, this is how a typical split-wire receptacle works, without burning your house down if you plug a toaster in the top and your hairdryer in the bottom...

 

If any bit of this is just plain wrong, please someone let me know before I hurt myself.

Edited March 30, 2005 by PatrickNeary

[John Pytlak RIP]

If any bit of this is just plain wrong, please someone let me know before I hurt myself.

<{POST_SNAPBACK}>

 

Sorry, but if you have to ask, you do risk hurting yourself. :unsure: Please get a licensed electrician.

[Patrick Neary]

apologies, i was just making light of it, you're quite right- That service panel is a very scary place, as it should be.

 

i hope that my post, while sounding pompously authoritative, isn't mistaken for any kind of "how to", it wasn't intended that way.

 

That is my understanding of how it works, though. Despite its unforgiving nature, or maybe because of it, I find electricity to be interesting stuff... :)

[John Sprung]

To clarify (or just correct) my earlier post, as I understand this kind of set-up, because each hot wire (from the 220 circuit) is out of phase with the other, the neutral will only carry the difference of the two new 110 branches.

<{POST_SNAPBACK}>

That's correct. Neutral carries the difference in any two leg single phase application. What is potentially a problem with stove (though not usually dryer) plugs is that they may not *have* a neutral. A four wire receptacle will give you Hot-A, Hot-B, Neutral, and Ground. An old three wire may be HHN or HHG. Either way, you'd have to use the same path for both neutral and ground, which NEC no lorger allows. The simplest way to put it is that a connection between neutral and ground is required at the service entrance, and forbidden everywhere else. Ground gets connected to the exposed metal parts of all the equipment you use, so it's important to make sure that it's unlikely to accidentally turn hot on you. Things are required to be grounded so that if a hot wire ever touches them, it'll trip the breaker.

 

As for how much power is available in U.S. installations, all general purpose branch circuits are either 15 amp or 20 amp, and it's been that way for nearly a century. If you can only pull 6 amps in a room, it's because of other loads on that circuit elsewhere in the building. The older the building, the less power it's likely to have. My place, built in 1926, has a one leg 30 amp main. I'll be upgrading it to two leg 400 amp.

 

 

 

 

-- J.S.

[Paul Bruening]

THE CONTENTS OF THIS POST HAVE BEEN REMOVED BECAUSE THIS WEB SITE DOES NOT WANT TO BE AT ALL RESPONSIBLE FOR ANYONE'S DEATH. :(

 

If somebody wants to post instructions like these, post them on your own site and link to them.

 

 

 

....here's a guerilla formula.....

[David Mullen ASC]

I can't believe you just gave someone directions on how to do their own tie-in. Why not tell them how to make their own explosives while you're at it? And load their own blanks? And do their own driving stunts?

 

Here in California, it's illegal to do your own tie-ins unless you're licenced and certified so don't even try. I don't know what the laws are in other states.

 

My advice: JUST DON'T DO IT.

 

As for crystal-sync silent gennies for sound filmmaking, even IF one caught on fire (and I've never seen it happen) usually they don't take a whole house down with it, being parked out on the street. But I don't advise a total novice tackling a gennie either. As for portable Honda putt-putt gennies, they are next to useless unless you are shooting a silent movie.

 

My advice: if you are not a trained electrician, limit yourself to using lights that are under 20 amps and only use them in circuits that can handle that, watch the load you put on the circuit, learn where the breaker box is, have a fire extinguisher on set, and be safe in general around electricity.

 

Anything beyond that, hire real electricians.

[John Sprung]

In the olden days, we used to do tie-ins all the time. It was standard practice on nearly every location. They even taught it in film school. I must have done it dozens if not hundreds of times, never got a shock or started a fire. I even tied in to pre-WWI delta connected three phase once. The only thing the DWP cared about was that you go in after the meter and pay for the juice.

 

But now the times have changed and the laws have changed. We have become a more timid and ignorant society. So, don't do tie-ins.

 

Today you also have HMI's, Kino-Flo's, and fast film that we didn't have back then. So you can probably live without tie-ins until you have a big enough budget to afford a genny and operator.

 

 

 

-- J.S.

[Robert Hughes]

I don't think it's so much a matter of timidity in society as it is the greater total number of people in general, and inexperienced youngsters in particular. I've done safe, live tie-ins to bldg services before, but don't wish it on anyone who doesn't have first-hand experience with the ways that electricity can suprise you. Electrical services have become so reliable and trouble-free in the past generation that a lot of younger people have never experienced a serious mishap, and don't know the potential for danger waiting behind that panel cover.

 

A flash arc isn't just a big spark; it's an explosive, self sustaining electrical short through the air, traveling through vaporous copper that is evaporating off the electrodes. If you don't have a sufficient appreciation for what that means, you don't belong near an electrical box.

 

I was in an old warehouse several years back, and was considering tying onto some wires in an old panel that I figured was 440v 3 phase. But it looked iffy, so I passed. It turns out the wiring was 16 Kilovolt and would have incinerated me on the spot before I could blink. I'm thanking my lucky stars I was timid.

Edited March 31, 2005 by Robert Hughes

[Paul Bruening]

Thanks John and Robert,

 

I apologize for offending any group members and mediators. That was not my intent. I come from that older tradition where you do it yourself. It is still a standard of manliness in these parts of the country. Electricity, while dangerous, is no great mystery. Man has been harnessing its powers for some decades now. It is something that can be learned and mastered with safety to all persons and property. With that in mind, low budget producers are faced with the real challenges of achieving high budget looks on no money. More light helps and that has to be powered by realistic supplies. It has to come from somewhere. I have never performed a patch that went bad nor have I known anyone who has had a bad patch. I am definetly not trying to pick a fight with anyone here. Nor, am I trying to awaken anyone's emotions or fears. Again, sorry about the trouble I caused.