Answer / thowsif_emerson_csm team

Working Principle of UPS:-
UPS is for the purpose to give un-
interruptible power
supply. This stores the energy in the form of DC by the
controlled rectifier (AC - DC converter) and discharge the
energy in the form of controlled AC by inverter (DC - AC
converter) so as to provide continuous power supply. Here
the back up is derived based on the requirement.

types:
1. Online Double convertion UPS (Normal High capacity UPS)
2. Online Delta convertion UPS (New technology offline
using buck boost Transformers)
3. Offline UPS (economical UPS medium capacity UPS 3 -
30KVA also available in higher capacity)
4. Line Interactive UPS (lower capacity UPS 300VA - max5KVA
output will be Squasi Sinewave).

UPS are used in home, medical, IT and industrial where the
critical load is used.


Static Transfer Switches :-

Static transfer switches in single
phase and 3 phase outputs suitable for use with two
synchronised or non synchronised input power sources, the
transfer switch provides a single output to the critical
load. This series of static transfer switches can operate
with the default source selected as A or B to feed the
critical load, on failure of the selected source the load
will be transferred in synchronism to the alternative
source. Sizes are available from 10kW to 1000kW with three
switching elements as standard for the three phase system,
a manual wrap around bypass switch is also provided. A
power flow status mimic and alarm indicating mimic with
separate digital or analogue metering is fitted as a
standard feature.

Answer / sakkaravarthi soganur

ups means un interuptible powersupply

ac voltage converted to dc voltage through converter
dc supply connected to baterry also connected to inverter
incoming so we convert dc to ac through inverter.whenever
normal supply failure at that time battry suplly used
without any interuption,
static switch means two scr's connected to antiparallel,and
also this is electronics switch,

pls,send the previous year written test questions.

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