Hi. I'm wondering if there's a tool of some sort to identify which power outlets within a house run off the same circuits. Or a tool that can identify how much more power that particular circuit can provide before blowing. I'm often fearful of accidentally drawing too much juice from the same circuit... especially when I'm in a residence that is not my own. Does anyone have any tips other than, choose the farthest outlet and hope it's not running on the same circuit? TIA
Questiong about running off house power...
- Thread starter morisato
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This will probaby end up sounding like a commercial about HMI, LED or fluorescent lighting but you got me on my soap box now ;-). When you start to become aware of some of the practical issues surrounding all this subject it makes you think about changing your approach to lighting. It's one reason I got interested in technologies that put out more lumens per watt than tungsten which is about 10 to 20 lumens per watt.
This subject really is a can of worms, especially in other people's houses. You never know what the age of the wiring or state of the safety circuits could be and of course that could be breakers or fuse boxes. And it IS somebody else's house too; so if you cause problems there, it can be awkward (if you see what I mean).
No tools I know about other than a brute force survey which would even include checking ground continuity in the extreme (are the grounds hooked up in the residence and is there even a ground pin on the plugs at all). To see what outlets are on what circuits is a question of just plugging things into them and turning off breakers and seeing what's still energized. But how can you really check the state of the wiring in the walls and how can you tell if the wires are getting too hot running 2 or 3 thousand watts of lighting?
There really are practical reasons for using low wattage lighting in video other than being "green" or conserving energy or not heating up talent and crew.
Many of the people here on this board are not using a soundstage with several 400 amp services but rather using a house with maybe one 150 to 200 amp service (or thereabouts) and residential grade outlets to run lighting and running over 1000 watts (about 9 amps dividing 1000w/110v) you start to get into shady territory where you're not sure if it's a good idea. Imagine the 100 year old apartment building in NY for instance. Was the wiring ever really brought up to modern standards?
In addition, even though each individual plug is rated for 15 amps or so in modern residential wiring you can certainly have several plugs on one circuit which means that the total of all of them can't draw more than the breaker of that circuit will allow. If its a 15 amp circuit then all the plugs should not have more than 15 amps total (about 1600w) running on them. If the breaker is running correctly, it should argue with your choices by turning off when it doesn't like what's going on. Do people get away with pushing these limits? Yes, everyday. Would anyone who is prudent recommend that you do so on a public board? Not me anyway.
I feel safe in running something like 220w fluorescent lights at a 2 amp draw and still getting adequate lighting for most things--with fluorescent that gives out over 800 watts of equivalent light (for anywhere you would have used a 800w softbox). Even with 440w at 4 amps you would still be hard pressed to find, in even the most wretched wiring, some problems waiting for you.
Sometimes you don't need soft light though and you need a LOT of light outside or whatever. HMI's (or metal halide) are extremely efficient too at 80 to 140 lumens per watt but still hot lighting--just not as hot as tungsten.
A 575w HMI puts out conservatively about 1600w of light and maybe more. Remember, that was the upper limit of a tungsten instrument on house wiring I mentioned earlier and that really IS the upper limit to of the circuit breaker on that line. But the 575w HMI is only drawing 575w actually--still well within the limits of safety for most situations you'll encounter. The 150w metal halide fresnel project I wrote an article about recently, is only drawing 150w but putting out about 500w of light. You get so much more light for your money and you're not pushing the limits of circuits as much.
And we haven't even covered LED's here which are about the best solution when no power is available at all, you've only got batteries and a generator is out of the question...
This subject really is a can of worms, especially in other people's houses. You never know what the age of the wiring or state of the safety circuits could be and of course that could be breakers or fuse boxes. And it IS somebody else's house too; so if you cause problems there, it can be awkward (if you see what I mean).
No tools I know about other than a brute force survey which would even include checking ground continuity in the extreme (are the grounds hooked up in the residence and is there even a ground pin on the plugs at all). To see what outlets are on what circuits is a question of just plugging things into them and turning off breakers and seeing what's still energized. But how can you really check the state of the wiring in the walls and how can you tell if the wires are getting too hot running 2 or 3 thousand watts of lighting?
There really are practical reasons for using low wattage lighting in video other than being "green" or conserving energy or not heating up talent and crew.
Many of the people here on this board are not using a soundstage with several 400 amp services but rather using a house with maybe one 150 to 200 amp service (or thereabouts) and residential grade outlets to run lighting and running over 1000 watts (about 9 amps dividing 1000w/110v) you start to get into shady territory where you're not sure if it's a good idea. Imagine the 100 year old apartment building in NY for instance. Was the wiring ever really brought up to modern standards?
In addition, even though each individual plug is rated for 15 amps or so in modern residential wiring you can certainly have several plugs on one circuit which means that the total of all of them can't draw more than the breaker of that circuit will allow. If its a 15 amp circuit then all the plugs should not have more than 15 amps total (about 1600w) running on them. If the breaker is running correctly, it should argue with your choices by turning off when it doesn't like what's going on. Do people get away with pushing these limits? Yes, everyday. Would anyone who is prudent recommend that you do so on a public board? Not me anyway.
I feel safe in running something like 220w fluorescent lights at a 2 amp draw and still getting adequate lighting for most things--with fluorescent that gives out over 800 watts of equivalent light (for anywhere you would have used a 800w softbox). Even with 440w at 4 amps you would still be hard pressed to find, in even the most wretched wiring, some problems waiting for you.
Sometimes you don't need soft light though and you need a LOT of light outside or whatever. HMI's (or metal halide) are extremely efficient too at 80 to 140 lumens per watt but still hot lighting--just not as hot as tungsten.
A 575w HMI puts out conservatively about 1600w of light and maybe more. Remember, that was the upper limit of a tungsten instrument on house wiring I mentioned earlier and that really IS the upper limit to of the circuit breaker on that line. But the 575w HMI is only drawing 575w actually--still well within the limits of safety for most situations you'll encounter. The 150w metal halide fresnel project I wrote an article about recently, is only drawing 150w but putting out about 500w of light. You get so much more light for your money and you're not pushing the limits of circuits as much.
And we haven't even covered LED's here which are about the best solution when no power is available at all, you've only got batteries and a generator is out of the question...
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SilverWolf
Veteran
There is a tool that you can use to check if a outlet is on the same circuit as another. you can even use it to check which one it goes to on the breaker.
Go to home depot or a store close to that in your area and look in the electrical section for a circuit finder.
Go to home depot or a store close to that in your area and look in the electrical section for a circuit finder.
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Great find.
I looked up the device that silverwolf is talking about and it is a set that comes with a special transmitter plug and an electronic wand. You just plug the xmit plug in each outlet one at a time and then wave the wand across the circuit breakers (or fuses) until you find the circuit attached to the outlet where the transmitter is. Looks like the wand makes noise or lights up to indicate continuity (you still need a ground fault detector plug though to check grounds if you need to do that). Next, take notes and then move the transmitter plug to another outlet and repeat the process until you've covered all the circuits you want to document.
So the trial and error method is not necessary if that thing is really effective. The one I saw online was $99 at Amazon.
http://www.amazon.com/Zircon-59353-Circuit-Finder-Pro/dp/B0001Q2VNM
I looked up the device that silverwolf is talking about and it is a set that comes with a special transmitter plug and an electronic wand. You just plug the xmit plug in each outlet one at a time and then wave the wand across the circuit breakers (or fuses) until you find the circuit attached to the outlet where the transmitter is. Looks like the wand makes noise or lights up to indicate continuity (you still need a ground fault detector plug though to check grounds if you need to do that). Next, take notes and then move the transmitter plug to another outlet and repeat the process until you've covered all the circuits you want to document.
So the trial and error method is not necessary if that thing is really effective. The one I saw online was $99 at Amazon.
http://www.amazon.com/Zircon-59353-Circuit-Finder-Pro/dp/B0001Q2VNM
Wilson
Active member
These devices have so-so reliability. You would save time and money by just knowing a few things. One, most bathroom abd kitchen circuits are bigger, 20amp, compared to the average 15amps.
Find the fuse panel and read up on the different kinds and how to check for a blown circut. Trail and error and common sense is the toll that I use in such situations.
Bring lots of extention cords and pull from outlets as far away as each other as is possible.
Good Luck!
Find the fuse panel and read up on the different kinds and how to check for a blown circut. Trail and error and common sense is the toll that I use in such situations.
Bring lots of extention cords and pull from outlets as far away as each other as is possible.
Good Luck!
SilverWolf
Veteran
You also can plug the transmitter into the outlet then wave the wand over another outlet to see if it's on the same breaker. The one I got from Home Depot in the States was about $30 dollars. I'm sure the have some more expensive one out there like the one you found
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Wilson said:
Yes plugging into as many circuits as you can is the key to all our type stuff given what we mostly have to work with. Spreading the risk across the different circuits is the best way to keep yourself out of trouble with higher wattages. And the more instruments of lower wattage the better. For instance, it's indispensible to have two 1000w lights instead of one 2000w IMHO, in that way you can split over two circuits rather than burden one over the edge of what it can handle.