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[email protected] clare@snyder.on.ca is offline
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Default How do we know when 120V US socket strip can handle Europe 240V?

On Tue, 20 May 2014 06:09:46 +0000 (UTC), "Geoffrey S. Mendelson"
wrote:

wrote:
No, to operate the same devices on 240 as on 120 it will only be
handling HALF the current. If the bar can handle the devices on 120,
it will have no problem, capacity-wize, on 240 because the current
will be MUCH lower.


Not always true. With a linear supply it would be true, as the different
transformer windings would both convervt the voltage down to the same
low voltage.

Switching supplies are not all the same, and some just convert the incoming
power to 400Hz (or higher) AC,run it through a transformer and reduce it
to the outgoing voltage with a regulator. If the device is plugged into
a 120 volt socket, the output voltage of the transformer is 15 volts,
if it is plugged into a 240 volt socket, it would be 30 volts.

The internal regulator would even it out.

Current draw would be the same.

Geoff.

Reguardless - they will never draw MORE current from 240 than they
would on 120 - so current capacity is never going to be an issue - and
MOST will draw less current on 240. One of the advantages of switch
mode power supplies is higher efficiency.