equipment power rating: is it instantaneous consumption?

Pls I'm a little confused about the rating of electrical equipment. For instance an equipment is rated 80W, could this 80W be the instantaneous consumption by which in 1hr it would have consumed 80x60x60=288KW?

I need this to be able to calculate type of load I can put on a inverter i'm trying to design and for how long I can do that.

Best regards

folarinv said:

Pls I'm a little confused about the rating of electrical equipment. For instance an equipment is rated 80W, could this 80W be the instantaneous consumption by which in 1hr it would have consumed 80x60x60=288KW?

I need this to be able to calculate type of load I can put on a inverter i'm trying to design and for how long I can do that.

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You're complicating things with no reason, basically by mixing up units. If your equipment is rated at 80W you need an 80W inverter, or preferably slightly higher - I would suggest at least 100W. A lot depends on what the load actually is?, you may need an even higher power inverter to allow the unit to start-up.

Your mistake is suddenly changing from watts to watt-hours, if something is rated at 80 watts, then in one hour it will use 80 watt-hours, or in ten hours 800 watt-hours (can also be written as 0.8 kilowatt-hours).

this does beg the question of what is the wattage rating. Peak, average or ?? I've always suspected that it's a fairly loose rating.

philba said:

this does beg the question of what is the wattage rating. Peak, average or ?? I've always suspected that it's a fairly loose rating.

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It's got to be loose, there's very little electronic equipment that will have a specific consumption, most things will vary according to use - for example, your TV set will vary greatly, depending how loud the volume is at any one instant, and (even more so) on the brightness of the picture.

An LCD TV is more constant, but at a constant high rate, as the display tubes remain at a constant level. Many sets do have 'energy saving' settings, where the brightness of the tubes are reduced.

But, as with any honest rating, the values quoted are RMS ones.