Does anybody know how to change the currency from 110 Volts, 60 cycles
to 240 volts 50 cycles.
which we use here in Australia?
Any information will be much appreciated.
Regards,
Peter Mason
> Does anybody know how to change the currency from 110 Volts, 60 cycles
> to 240 volts 50 cycles.
> which we use here in Australia?
The frequencies are not line-locked.
Get a 240-to-120 transformer of the required capacity.
North America hasn:t been 110 volts since before WW-II, and it was 117
volts, average, immediately after WW-II, and 120 volts since the 1950s.
--
CinemaScope�: The Modern Miracle You See without Special Glasses!
>
>Get a 240-to-120 transformer of the required capacity.
>
That would be an option, albeit a superfluous one, considering the
projector is supplied with a switching power supply, 100-240V 50/60Hz.
When you say "switching power supply" do you mean the projector
automatically detects
what voltage it is being supplied with and automatically switches over
to that circuit?
Regards,
Peter Mason
He means "switching" in its modern electronic sense: rather than using a
big-iron-cored transformer that runs at line frequency (50 or 60 Hz) to
step down the voltage to the lower voltages used internally, the power
supply uses semiconductor switching devices to "chop" the input power at
a higher frequency (on the order of 100 kHz). The input voltage can
then be more efficiently down-converted by a smaller, lighter-weight
transformer optimized for that high frequency. Also, regulation of
output voltage is managed by pulse-controlled switching devices that are
(ideally) either completely on or completely off, so that the overall
efficiency of the supply is much greater than an old-fashioned linear
regulated supply -- and less heat is dissipated in the power supply.
The control circuits which manage the process are generally able to keep
a constant output voltage over a very wide range of inputs, as in the
specification above. In recent years these control circuits are
integrated onto an inexpensive chip so that switching power supplies are
now common even in consumer gear.
Look at the power "brick" that supplies your camcorder or laptop
computer, for instance; its spec will often be 100-240V, 50/60 Hz, which
means it's a switching supply. Quite often the line cord will be
detachable from the brick so that the same universal "brick" can be used
with any of several line plugs depending on the locality in which the
device is sold.
For more details, see
http://en.wikipedia.org/wiki/Switched-mode_power_supply
-Neil Midkiff
No.
A switching power supply directly rectifies the AC power line to make high
voltage DC, then it has a high frequency switching oscillator that chops it
up into high frequency AC. This means the step-down transformer can be a
teeny tiny ferrite transformer that is cheap to make, instead of the huge
piece of iron that would be required at 60 Hz.
Switching supplies have become pretty much ubiquitous in consumer electronics
today. They are efficient and light. They are also more touchy about power
line noise and are a real devil to repair when they break.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."
So if I buy a projector from the USA can I use it by connecting it to
240 V 50 cycles (assuming I change
the plug) here in Australia?
Will it make any difference if it is connected to 120V 60 cycles
(American) or
240 V 50 cycles (Australian).?
Regards,
Peter Mason
That would depend upon the power supply. There should be a sticker on it
that says what input voltages and frequencies it will accept.
Most of these (at least the larger ones) use standard IEC power cords (same
as most computer power supplies), so you can just use an existing cord that
is lying around, assuming that the power supply will work with your voltage
and frequency.
--
Scott Norwood: snor...@nyx.net, snor...@redballoon.net
Cool Home Page: http://www.redballoon.net/
Lame Quote: Penguins? In Snack Canyon?
And since we've already discussed the specification of the power supply, the
answer is YES - just plug it in. It has a standard IEC plug, and a switching
power supply rated for 100-240V, 50/60Hz, so it will work anywhere.
Regards,
Peter Mason