How many watts is my system using?

If you have a 100 watt light bulb, is that a 100 watts per second, per minute? The answer is not "per" but a constant wattage over the period the light bulb is burning. A watt is a watt - you cannot divide it - it's a 100 watts when you flip the switch and still a 100 watts just before you flip it off. If you leave the light on 24 hours a day, then the energy used in one month will be 30x24x100 = 72,000 watt-HOURS. Not watts per (divided) hour but watts multiplied by hours.

If you want to know how many watts per hour or minute, you would first have to determine over what period the light bulb burns. To a utility company 72,000 watt-hours (or 72 kilowatt-hours) at a rate of 10 cents a kilowatt hour, $7.2 to burn that bulb all month.

Per hour.

Your electric company charges by the kwh or per 1000 watts. To figure how much you stereo is costing you the formula would be: 732 watts = .732 x "the kwh rate". So if the rate was say 20 cents per hour, you would be paying 14.64 cents per hour, not so much, BUT if you leave it on 24/7, you will be adding $105 a month to your bill. You will probably get a Xmas card from them.

Gs5556 Thanks for your detailed answer the light is now on.

Mystang,

Yes your calculation is correct...

Thank you all. I just got a tube amp and noticed that the reading on my conditioner went from 4.9 Which is what my s.s. Amp And system used to 6 amps now that I have a tube amp. I do turn the system off when not in use to keep from going broke.

Maybe this will help with the "time" or "rate" question. The unit you are speaking of, the watt, is a unit of power. Power is energy per unit time. 1 watt is 1 joule per 1 second. So time is "built into" the "watt". That is, the watt is, by definition, a rate. If you are dissipating 1 watt for 1 second you 'use' 1 joule, 1 watt for 2 seconds = 2 joules. The utility company is technically charging you for energy usage. The unit is typically a kW hr - a larger unit than a joule, i.e. 50 KwH = 180000000 joules. Why is any of it important other than the electric bill? Think of energy as heat, that is what the big deal about power really ends up at in electronics.

Mystang - "I'm using 6 amps when my system is playing music" something doesn't add up - If you use class A amp then your supply power is always the same with or without music but if your amp is class AB then your average power is in order of few watts and cannot possibly be 732 watts. Since average power of the music runs in order of few percent of the peak power your amp is likely to be class A (about 50W per channel) or similar wasteful scheme.