cynic wrote:
On 12 Jan, 19:57, John Rumm wrote:
cynic wrote:
Any flourescent light has a power loss in the choke/control gear. If
This is true...

you check in the OSG for a rule of thumb this is normally taken as not
less than 80% of the rated power of the lamp thus a 100 watt lamp
fitting will consume 180 watts of power or more. Your readings are
entirely ok
You seem to be confusing the current demand, and power dissipated in the
load. The maximum circuit current may well be in excess of that expected
by inspection of the lamp power alone, however not all of that
additional current flow corresponds to matching power dissipation (and
hence energy consumption) in the load.

I do know the difference and very much doubt the el-cheapo meter
readout is actual watts power. It is likely to be reading va and the
readings mentioned fit reasonably well with that. Maybe I should have
given a fuller description :-(

I have one of the plug in meters somewhere (the one Maplin flogged for a
while)... IIRC the one I have does make a stab at assessing power
factor, however it is probably not much good on things that have non
sinusoidal current waveforms like CFLs. It seems ok on basic reactive
loads with straightforward leads or lags though.

(spose I ought to dig it out and work out why this house is so much more
expensive than the last one for electricity use)

--
Cheers,

John.

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