Dimmer/Router Speed Controller

[Bad Daddy]

Hey Bruce (or anyone else),

I was looking at router speed controllers and they have variable amps they can take. What rating controller should I get for lighting?

Edit: While I'm asking, what amp rating do I want for extension cords?

[Nathos]

Pick the amperage of the outlets you intend to use the dimmer with. That would be the simplest and safest option. If you plug into multiple amperage outlets, pick the highest amperage you're going to use, and get a dimmer that handles that.

Keep in mind that different amperages use different shaped plugs and receptacles. A 20 amp plug won't fit into a 15 amp outlet. A 15A plug should fit into a 20A socket, so if you use 20A outlets...would be best to get a 20A dimmer, get a 15A plug on it. Though if an electrician tells you that's evil, listen to them. Fires are only cool in their proper time and place.

Do not get a 15A dimmer and plug it into a 20A outlet. That's asking for trouble.

Gauge of wire for extension cord depends on how many amps you're going to ask it to carry, and how far. 14 gauge wire will be fine for taking 15A up to 25ft. I use 12 gauge for 50ft cable runs at 15A. That's a bit conservative, but it's safe. How many amps, and how far do you need to run the lines?

Nathos

[Bad Daddy]

Gauge of wire for extension cord depends on how many amps you're going to ask it to carry, and how far. 14 gauge wire will be fine for taking 15A up to 25ft. I use 12 gauge for 50ft cable runs at 15A. That's a bit conservative, but it's safe. How many amps, and how far do you need to run the lines?

Nathos

Honestly, I'm not sure. Most of the IDFG lighting equipment isn't above 1000 watt lights. However, I don't know the amps or volts for those lights. For pug-ins, it's mostly connecting lights to standard house outlets (not sure what typical specs are on housing outlets).

[Nathos]

Majority of household wiring is 120V/15A in the USA. Outlets that look like:

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(two flat blades of the plug and holes in the outlet are parallel) are 15A/120V outlets.

Outlets that look like:

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(one hole in the outlet has a sideways-T shaped hole, plug has one blade vertical, one horizontal) are 20A/120V outlets. Each amperage and voltage has its own shape, assuming the outlets are installed in accordance with NEC code.

Lights are rated in wattage, given that your outlets are 120V, you can calculate how much amperage the lamp will draw by using:

Watts/Volts = Amps

a 1000W lamp consumes:

1000W/120V = 8.33A

If you try to exceed the amount of current (measured in Amps) that an outlet can supply, you got a problem. Properly done electrical work will be fused, and so you'll blow a fuse or trip a breaker. You have to account for everything that is drawing power off that circuit (note the word "circuit", not "outlet"). For example, in the room I'm in, there are at total of 3 outlets. But they are all actually all part of the same 15A/120V circuit, so if I plug a 1000W lamp into one outlet, and a 2nd 1000W lamp into another outlet...now I've got an attempt to draw 16.66A total, and the circuit breaker for my room just tripped. On location, it's good to have someone around that might know what outlets are part of what circuit...that, or access to the breakers/fuses, just in case =)

The simplest way to think of it is that for each "free' 15A circuit, you can safely plug in any combination of lamps that totals less than 1800W:

Examples:
1 x 1000W lamp OR
2 x 650W lamps OR
5 x 300W lamps OR
1 x 1000W and 1 x 650W lamp ... etc

assuming there isn't anything else significant attached to the same circuit.

As far as extension cords/wires/cables/stingers go, they have a capacity as well. Cables are measured by diameter of the conducting wire, which is measured in "gauge" aka AWG. Wire isn't perfect, there is some loss of power when you send current through it (you loose so much per foot). So size (gauge) of wire you need to carry the current for your lamps depends on how much Wattage you have on the end of the cable, and how long the cable (plus the length of the lamp's cable) you need to run. 14 gauge cable is fine for extension cords up to 25ft, 12 gauge cable is fine for cords up to 50ft. That leaves plenty of margin for the lamp's cable, and you can draw up to 15 Amps through the cable without worry.

[Bad Daddy]

Thanks for the info. It's been awhile since I've taken physics so the refresher was nice.