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Bypass
A power path around a UPS system. An automatic bypass is used by the UPS to switch its load to the mains if it experiences an overload or internal failure. A manual, maintenance or service bypass allows an engineer to isolate, maintain or remove the UPS without interrupting power to the load.
http://www.upspower.co.uk/ups-products/choosing-a-new-ups/up...

Un bypass eléctrico es una desviación de un circuito eléctrico que permite la comunicación directa entre dos puntos, es decir un puente que puede soportar la potencia del caso y que se le incluye al UPS. Esta derivación entra en forma automática para pasar la carga que soporta el UPS a la red eléctrica principal del sitio cuando se detecta una sobrecarga o hay una falla interna en el UPS que no permite actuar como tal. también es una medida que toma el ingeniero de mantenimiento para aislar el UPS sin causar ninguna falla en el servicio de energía al circuito servido por el UPS.






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Note added at 15 hrs (2015-05-30 11:41:22 GMT)
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your unsource definition
Un bypass eléctrico es una desviación de un circuito eléctrico que permite la comunicación directa entre dos puntos.
http://www.significados.com/bypass/

Term Hacer un puente(eléctrico)=puentear
http://forum.wordreference.com/threads/hacer-un-puente-eléct...

For your defintion of shunt
shunt SpeakerListen:Scot
/ʃʌnt/
in Spanish | in French | in Italian | English synonyms | in context | images
WordReference Random House Learner's Dictionary of American English © 2015
shunt /ʃʌnt/ v.
[~ + object]to force or turn (something) aside or out of the way:to shunt the tanks off to the side.
[no object] to turn to the side:The railroad cars shunted off to the side.
Surgery[~ + object] to change the direction of the flow of a fluid by means of a shunt.
n. [countable]
the act of shunting;shift.
Rail Transporta railroad switch.
Surgerya channel through which a bodily fluid is sent off from its normal path by surgical connection or by insertion of an artificial tube.
Collins Concise English Dictionary © HarperCollins Publishers::
shunt /ʃʌnt/ vb
to turn or cause to turn to one side; move or be moved aside
to transfer (rolling stock) from track to track
to divert or be diverted through a shunt
(transitive) to evade by putting off onto someone else

n the act or an instance of shunting
a railway point
a low-resistance conductor connected in parallel across a device, circuit, or part of a circuit to provide an alternative path for a known fraction of the current
a channel that bypasses the normal circulation of the blood: a congenital abnormality or surgically induced
Brit informal a collision which occurs when a vehicle runs into the back of the vehicle in front
Etymology: 13th Century: perhaps from shunen to shun
'shunt' also found in these entries:
http://www.wordreference.com/definition/shunt Also Collins Dict.

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