Power has to be the largest concern at any LAN Party. Poor planning of power distribution can turn a fun event into a not so fun session of sitting in the dark. I see quite a few people out there running parties without the preper knowledge of power in relation to computer equipment, so for F.R.A.G.'s sake and others, this stuff should be written down.

This document is not written in stone. It's a text document actually and it can be modified and updated to reflect the most accurate information possible. If you see something that is wrong or needs to be clarified, send me some e-mail and I will update this page. Me being Bad Mojo, mojo@rps.net.

Basic Theory (FuseBoxes, Breakers, Circuits, Electricity)

Basic Electricity Concepts

Electricity (I can attest to) will shock the ever living crap out of you. Be careful with it and treat it with respect and it will (grudgingly) provide you with power. I learned a lot about electricity in school/college and then I forgot about it. Then I wanted to host a LAN Party and I kicked myself for not remembering. Doh!

Watts = Volts * Amps

This is the equation that will do it all. If you are in the United States, V or Volts will be about 120 or less. Basically the standard feed to a house in the united states is two 120v legs or a total of 240v. Some large building will have a higher feed, but they know that the outlets will need to provide a typical house voltage to stay within the standard. So outlet circuits in any place you hold a party should be 120v. Makes things simple ... kinda. Remember a few sentances back when I said `about 120 or less'? Well, electricity loses it's voltage over distance. And after a long run to your house and that long run through your 100' extension cord ... it might not be a full 120v. Plan on 110v being what's actually at the fusebox.

Speaking of the fusebox ... breakers will normally be rated by Amps. If you know the Voltage (we do), and the Amperage of the circuit (we do if we look in the fusebox), then we know how many watts we can put on the circuit. A typical 15Amp, 110v circuit can support 1650 watts. Woo hoo!

Simple Building/House Wiring Concepts

A breaker is like a fuse. Except when it's tripped, it can be reset by simply flipping the little throw switch back to ON. Saves you money by not having to buy expensive fuses everytime you mess up. Go find your fusebox. Open it. Stare at it. Look at the breakers closely. Good, read on.

In any building or house, a circuit refers to the wires providing power from the fusebox to any appliance, light, or outlet. Each circuit has one breaker in the fusebox. Once you get to commercial or industrial buildings, circuits tend to allow more amperage and cover less outlets per circuit (which is a good thing).

Power enters the building via the fusebox, where it is distributed among the many circuits. There is a breaker that isolates the fusebox from the main power feed, and there are breakers that isolate each circuit from the main power feed. The purpose of the main breaker is to keep the total power usage of the entire building from exceeding a certain amperage. Each of the smaller circuit breakers prevent each circuit from exceeding a smaller amperage. This places two limitations on your power needs. You can't exceed the main breakers amperage or the individual circuit breakers amperage. If you stay under the smaller circuit breakers amperage limit, you should never have to worry about popping that mighty big main breaker. If the main breaker pops due to heavy draw, the entire building will lose power, so it's worth the simple calculation if you can make sure you'll stay under it's limit.

At this point you might ask `Why do we have fuse boxes that limit our power draw?' It is very good that you ask. If you draw 20Amps of power over a 10Amp extension cord, there is a good chance the cord will melt, spark, or even catch on fire. Imagine those conditions inside the walls of your house. The breakers prevent you from abusing or damaging the wiring inside your house, and the wiring to the power company overall. On this note I will warn you not to alter or change the wiring or fuses in your house or building unless you are a trained electrician and know what you are doing.

Power Emergency Sequence

Computer Hardware

In an ideal world, computers and all of their accesories would receive power from the power supply and that would be it. But people run powered speakers and can't plug their monitors into their computers power supply. This means that you need to generalize the most power hungry computer you can, and assume everyone is going to bring one. This is called planning for the worst while hoping for the best.



There is good news and bad news about monitors. The bad news is that larger monitors that most people want to use today are power hogs. The monitor on my desk at work is 17" and rated at 2.1Amps. That's 231 watts, almost as much as a computer itself! There are two good points to monitors. If you have the proper kind of power supply in your system case, you can power your monitor off of your computers power supply. I do this and it helps cut down on power drain since your computer won't use all of the power that power supply can make anyways (unless you're running 12 SCSI drives, 4 CD-ROMs, and every slot filled). Monitors also normally only draw their full Amperage when they are first turned on. Once on and warmed up, monitors tend to draw about 60% of their listed amperage. As long as you don't have 10 people with 21" monitors power on at the same time, the monitors won't cause much impact. If the power goes out, and people leave their systems on and you flip the breaker and all of those monitors power up and start to draw ... they might pop the breaker again. Refer to the power outage emergency sequence.

Standard CPU		300w
17" Monitor		139w (60% of 231w)
Total			439w (or 3.9Amps)

Mapping Power

So you just rented or borrowed that huge warehouse and now you want to know what breakers/circuits control what outlets/lights. A very valid question. If you are lucky, the place wil be able to provide a map of the power and how many amps each circuit provides. But chances are good that when you asked `Do you have an electrical map of the location?' they said `Huh?' Just like when you said `I'm holding a LAN Party.' This means YOU will have to do some work. I recommend getting a 50' extension cord, a radio or lamp, and any friends who said `I'll help you run a LAN Party!' Make sure you do this mapping on a day when you can abuse the power at the site, you'll be flipping breakers on and off and you don't want to be doing that while the place is being used.

1) Plug the radio/light into the extension cord.
2) Draw a diagram of the outlets in the building.
3) Draw a diagram of the fusebox.
4) Plug the extension cord into an outlet.
5) Start flipping breakers off, then on.
6) When the light/radio goes off, mark the outlet and the breaker with a matching symbol.
7) Repeat until you know what outlets are on what breakers.

If there are large appliances in the area, you may want to note which of them switch off when you flip breakers. Having a heavy duty freezer on your server circuit can cause problems when it's compressor kicks in and steals your power. Try to find out what EVERY breaker does. It's a little extra work but it can help if you know there's an extra outlet somewhere in case you need a back-up circuit during your party. Look at each fuse and there should be an amperage rating on each one. Now you can tell where the power is, and how much there is at each location. A 20Amp circuit will provide you with 2200 watts of power.