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[Azztech]

An electrician I'm not, but I was under the impression that a standard mains outlet was rated at about 10amps, therefor I'm not sure about 2X50W heat cords drawing 8 amps. Should that be correct I could be in trouble running 5X100W lights from the same point

your right, an electrician your not! in fact don't go anywhere near electicity with comments like this

the 8amp draw is calculated by this:

2 x heat cord = 100 watts
power supply (batteries) = 12 volts
amps = watts/volts

= 100/12 = 8.3amps.

if they were plug into 240 volts (mains) they would be .4amps as in 100(watts)/240(volts) = .4amps

you have to remeber that your looking at what wattage the INVERTER is drawing under 12 volt condiditons.