"Geoffrey S. Mendelson" wrote in message
...
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 convert 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.


I don't think that's correct. To (possibly over-) simplify things, at higher
line voltages, the pulse width will be narrower, and less charge will be drawn
from the filter caps. Ergo, less current will be pulled from the line.

On Tue, 20 May 2014 07:32:03 -0700, "William Sommerwerck"
wrote:

"Geoffrey S. Mendelson" wrote in message
...
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 convert 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.


I don't think that's correct. To (possibly over-) simplify things, at higher
line voltages, the pulse width will be narrower, and less charge will be drawn
from the filter caps. Ergo, less current will be pulled from the line.
Don't confuse Phil with facts - his mind, such as it is, is already
made up.