Why choose 120 volts?

joel jaeggli joelja at bogus.com
Thu May 28 10:20:36 CDT 2009


If the pdu contains a surge suppressor and was designed for 120v, plugging in to 220 will cause the MOV that protects against transient over-voltage to emit smoke. The breaker or fuse is a current limiting device.

Joel

Pete Templin <petelists at templin.org> wrote:

>Dave Larter wrote:
>> Seems like if the c14 was connected to a 240v PDU the 5-15 would
>> deliver 240v to the equipment, arc/pop tripping the breaker on the
>> PDU as soon as it is connected killing power to everything on that
>> PDU.  Or am I missing something?
>
>If you plug a PDU into a service that's higher voltage than expected, 
>why would the PDU circuit breaker trip?  That breaker is measuring 
>current, AFAICT, though in the end it might be measuring power. 
>Regardless, it isn't measuring voltage, because that isn't constant 
>(it's AC, after all) and is likely to drop under a short circuit, not 
>skyrocket like the current will.
>
>pt
>


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