Inverter help

[cat007]

Hey all

If I have a 12v-240v inverter and the device I'm running uses 240v and 260 watt - how many watts @ 12v will it draw from the battery?

Is it goign to be 260W or will it change somehow because its stepping down/up to 12v....

[sergei]

Hey all

If I have a 12v-240v inverter and the device I'm running uses 240v and 260 watt - how many watts @ 12v will it draw from the battery?

Is it goign to be 260W or will it change somehow because its stepping down/up to 12v....

How many watts? if inverter efficiency is about 60-80% so then it will draw 300-360W.
Perhaps you meant amps? roughly 25A-30A.
Power=Voltage * Current.
How long you battery lasts? If it is a standard NS40 style, under 1 Hour.

[cat007]

How many watts? if inverter efficiency is about 60-80% so then it will draw 300-360W.
Perhaps you meant amps? roughly 25A-30A.
Power=Voltage * Current.
How long you battery lasts? If it is a standard NS40 style, under 1 Hour.

I have one of these: http://linux.supercharge.com.au/product_detail.php?seq=84

The inverter is an 800-1000 watt continuous (1600-2000W surge) - is that the 240V power rating? 800watt @ 240volt is 3.33amps - but 3.3amps @ 12volt is only 39watt??? I'm confused as hell lol

[sergei]

How many watts? if inverter efficiency is about 60-80% so then it will draw 300-360W.
Perhaps you meant amps? roughly 25A-30A.
Power=Voltage * Current.
How long you battery lasts? If it is a standard NS40 style, under 1 Hour.

I have one of these: http://linux.supercharge.com.au/product_detail.php?seq=84

The inverter is an 800-1000 watt continuous (1600-2000W surge) - is that the 240V power rating? 800watt @ 240volt is 3.33amps - but 3.3amps @ 12volt is only 39watt??? I'm confused as hell lol

You should add approximate efficiency loss to 800W (say 100W) and then divide it by 12V that way you will get current.

[whynot]

two simple formula to remember V=IxR and P=VxI

V is volts, I is current in amps, R is resistance in ohms and P
is power in watts.

300w at 240v is 1.25amp where 300w at 12v is 25amp

take into account efficiency of the inverter and you should have an answer
oh and when you try this with some amplifier ratings the pmpo rating seems pretty optimistic