I seem to be running out of wall sockets in my home. Each will socket has two wall plugs in them. If I bought two six socket voltage dividers and plugged both into each wall socket, am I creating a fire hazard?
I have a 6 socket thingie in every wall socket in my room, and have had no fires for 2 years. I guess it depends on what you plus in though. I have mostly game systems and other electronics that I rarely use while another on the same strip is on. I imagine if you were trying to plug in appliances and/or power tools, it might be hazardous.
No, The main things that are being plugged up are mainly:
Computers and Periperials,
Table lamps,
TV’s,
Stereo’s,
DVD players,
VCR’S,
Power Supplies for Telephones,
Alarm Clocks,… ect
*Nothing that would think would draw a lot of current *
The fire hazard comes from 2 main sources: the amount of current running through that particular circuit, and extension cords fraying from being trod upon.
A typical household wall circuit in North America is rated for 15 amps. If you keep the total load to 10-12 amps, you won’t have much of a problem. This also assumes the circuit is 3 wire. If it’s 2, keep the load less than 8.
If you don’t know what a particular device draws, look at the back. There will be a plate describing the power consumption, and find the load number. It will have units of either Watts or VA (Volts x Amperes). Divide by 110, and the result is the drawn current. As an example, a 100 W lightbulb draws about 1 amp. Add up the drawn currents for everything on that circuit. Hint: lights and anything with a heating element will be big power hogs.
I leave protection of extension and power cords as an exercise to the reader.
Oh, I like the tagline about dogs on the space shuttle. I’ll pass it up the management chain. Nit: the acronym is NASA, not Nasa 
Generally speaking, they are safe. I have my entertainment system and computer set up that way, too many things to plug in for plain sockets. I used a 10 outlet, double width strip (5x2) and mounted it on my wall behind all the stuff. Obviously, there are things to watch out for. Don’t overload any individual outlet with high current devices. Don’t chain power strips by plugging a strip into another strip, you should only plug strips into the wall socket itself.
I prefer mounting them on the wall if possible, that makes it less likely for the plugs to get knocked around or stepped on.
Please do not plug any of the following into a multi-tap adapter or extension cord:
Vacuum cleaner
Iron
Hair dryer
Toaster oven
Microwave oven
Refrigerator
Space heater
Air conditioner
Shop equipment (e.g. table saw, planer, compressor)
Large household appliances (e.g. dishwasher, stove, washer and dryer)
This is not an exhaustive list. Read the manual; determine the current or power draw of each item. Do not defeat safety features. If it has a three-prong plug, plug it into a grounded outlet. Change the battery in your smoke detector. Know two escape routes from your house. Oh. And “Don’t drive on the railroad tracks!”
vunderbob is right, it’s not the voltage that is an issue.
I’m currently teaching electrician classes in Pennsylvania, where common ampere ratings for an outlet are either 15 (slightly older) or 20 amps, so you definitely want to check your outlet and your breaker for the current limit. Try to stay under that by about 1 to 2 amps, or you run the risk of causing a fire.
Also, if you get any ideas about replacing the outlet boxes in the walls themselves, check your breakers first. What you don’t want to do is use a 15 amp rated outlet box on a 20 amp breaker circuit. The metal cannot withstand the heat of the higher current, and melts.
Houses are wired in parallel, such that voltage does not divide between outlets, but current does. The six-outlet box you put outside the wall that plugs into the wall would also divide current but not voltage. Household items are designed to operate at around 110 V and their resistive components will draw as much current as they need.
Happy extensioning.
Make sure the power strips you buy are UL-listed. In fact, make sure everything in your home that uses electricity is UL-listed. That means they’ve been through at least some independent testing to make sure they don’t burst into flames for no particular reason.
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At my former employer, we were doing some software development on new computer hardware provided by a large Korean electronics manufacturer. Along with the hardware, they sent a box of power cords - the kind you use on a PC. We plugged one system in, got a loud bang and some smoke from the now-fried power supply. Some investigation showed that the power cord manufactured in Korea had reversed hot and ground wires! We quickly tossed the entire box.
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Since when did 15 amp branch circuitry become obsolete? 20 amp branches are only required in a handful of locations for dwelling units. So long as the ampacity of the overcurrent protective device is consistent with the sizing of branch circuit conductors, the risk of fire is negligible.
How do you account for the proliferation of nonmetallic device boxes? Cite, please.
Fooey. Any appliance can be plugged into any receptacle on a branch and draw up to the limit of the overcurrent protective device, as such current is additive, not divided. Were your statement about resistive components true, then how would one control devices using a rheostat?
Plugstrips and extension cords have the same problem-abuse/misuse. Article 400 covers Flexible Cords and Cables. 400.8 Uses Not Permitted. Unless specifically permitted in 400.7, flexible cords and cables shall not be used for the following: (1) As a substitute for the fixed wiring of a structure. 400.7 Uses Permitted (A) (11) Temporary wiring as permitted in 527.4(B) and 527(C) which refer to Temporary Installations. 527.3(B) allows temporary installations for a period not to exceed 90 days, together with other constraints. All references 2002 National Electrical Code®. Bottom line-if you need additional receptacles, have them installed by a qualified, trained person.
Every single one of the breakers in my brand new house is 20 amp, and all of the outlet boxes themselves are 20 amp, which the electricians and the inspector seemed to find rather normal. Same holds true for the other homes in my neighborhood, as most of the people there ‘toured’ around all the homes as they were going up, and me being the nerd I am, I asked about ours to see if it was a common thing.
Which is why you don’t put in the wrong guage of wiring or the lower-ampere rated outlet box than the circuit breaker is rated for. In other words, 24 guage wire and using an outlet box rated for 5 amps will not do when the OPD is rated at 15 or 20 amps. I am not seeing your quibble here.
Cite of what? That more current than a certain guage of metal can handle is going to overheat it and can melt it?
That there are device boxes that are built out of plastic? Tell me, what are the conductors that are put into those boxes made of?
The total current supplied to a parallel circuit is divided to each branch of that circuit, thus the total amount of current drawn by all the branches of the circuit adds. Or would you say that the 200 Amp service entrance to a newly wired house (and I’m going with my neighborhood, in Pennsylvania, which was built within the last two years as having 200 Amps) is not divided among all the branch currents in the house? Those branch currents are, you’re right, added to get the total amount of current drawn from the source.
If you’re considering the outlet, or the OPD (circuit breaker) to be the ‘source’ of the current, then that current will be divided by all the branches connected in parallel to it. The sum of all the branches will be the current supplied up to the limit of the OPD. Which means that if you have 6 devices in parallel with each other that each draw 1 Amp, the total current drawn will be 6 Amps. That 6 Amps will divide (not always evenly depending on the loads) among each branch in the circuit.
You’re looking at it branch to source, I looked at it source to branch.
Rheostats operate by varying resistance, which means that if you raise the resistance, less current will be able to flow through that device. If you lower the resistance, more current will be able to flow through the device. All else being equal, the total current drawn by the circuit will change in accordance with the change in current through the rheostat.
So you’re saying that if someone needs to plug in that surge protector for their computer which will require a monitor, printer, box, and probably speakers, they’re going to need a place to plug in four things and should have another outlet installed by an electrician rather than purchasing and using their 20$ surge suppressor?
My god, I’m not suggesting that people make outrageous changes to their wiring as in National Lampoon’s Christmas Vacation. What I’m saying is that if you’re going ot hook up that computer, as long as the total of the currents through the devices in the surge suppressor are not more than the OPD, wiring, and box itself can handle, I can see no reason why the six outlet surge suppressor is bad. It becomes bad when you’re attempting to do something like circumvent the OPD and the wiring’s limitations by doing something like installing a larger amperage OPD and then plugging in fifteen hairdryers to your daisy chain of four power strips.