Answer / sameer hussain

online ups is a double conversion(dual) ups which firstly
converts AC power to D.c ,then D.c to A.C .the stored D.c
form of electricity remains within the batteries. in online
ups systems load is always connected to inverter. in online
ups system the power supply goes to the end user through
the battery,if there is A.c power cut ,then no harm or
interruptibility occurs .

APPLICABLE IN CRITICAL INSTRUMENTS LIKE C.T SCAN,X-
RAYS,ULTRA SOUND,OPERATION
EQUIPMENTS,SPECTROSCOPES,COMPUTERS ETC......

by SAMEER HUSSAIN
(M.E)
SNA POWER ENG. PVT LTD LUDHIANA

while in case of offline ups sytems the raw A.c supply is
connected by a realy type of mechanism,then the battery and
inverter is bound tothe msin supply. so when there is A.c
Power cut ,the really needs a time gap of 3-5 ms to shift
it to battery mode.

Answer / nb subrahmanyam

ONline ups means,when ever raw power supply
fails ,automatically it will supply power to load with out
time gap(beacuse of raw power is connected through
innverter)

in the case of OFFline ups,whenever raw supply fails,it
will supply the power with time gap (beause of inverter
connected to load after raw power fails)

Answer / vivek yadav

online ups have no change over time but offline ups have a
change over time around 8 milli sec.

another difference is that online ups have less dc
capacitor bank but off line have more dc capacitor


online ups have a DOM type switch
offline have a toggle switch

Answer / ram kumar saini

online ups will give continuse supply wheater power fail or
on.
Offline ups give supply only when power supply off.

Answer / raj

In online ups inverter is always on when ac supply goes off
ups give power but in offline ups inverter always in off
condition inverter on when power goes off.

Answer / renjith mr

Online UPS powers the load from Battery always whereas Offline UPS powers it only during power failure. Online UPS is needed only for equipments where the power failure is not entertained even for milliseconds.

Answer / md. akhter-uz-zaman

The true advantage to the on-line UPS is its ability to
provide an electrical firewall between the
incoming utility power and your sensitive electronic
equipment. While the off-line and line-interactive
designs leaves your equipment connected directly to the
utility power with minimal surge protection, the
On-line UPS provides an electronic layer of insulation from
power quality problems. This is accomplished
inside the UPS in several tiers of circuits.

Answer / vijay prashanth t

Online UPS: We can also define this as true online, double
conversion UPS. This UPS will convert the AC power in to DC
and again DC to AC. And thats why, this is called as double
conversion UPS. The output of an online ups will be pure
sine wave always. The connected load is always in Inverter.

Offline UPS: This UPS will regulate only the voltage
tolerance and there will not be any protection for spike or
frequency tolerance. The output of this UPS will not be a
pure sine wave. The connected load is in Inverter only when
the power fails.

Answer / ompal

online ups connected with software and can work with pc

Answer / sub surjeet singh

in on line UPS out put is allways taken from invertor hence
o/p is isolated from input and there is no effect of input
voltage varriation in output.
in off line UPS when AC mains is present in the input that
is taken from output and when AC mains in input cut off
than change over to invertor and output is taken from
invertor. hence when ac mains is present output of UPS is
effacted when input mains voltages up or down.

How can I known multiplying factor .without multiplying table

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