Answer / roshan khadka

In on-line UPS,the batteries are always connected with
inverter so that there is no power transfer switch between
them and load is always connected through inverter whether
there is power supply or power on.

In off-line UPS, load is connected directly with ac source
in normal operation and battery charging will be there
during that period. But in case of power failure,load is
connected to the inverter via power transfer switch between
battery and inverter.

Answer / shubham patel

An off-line UPS remains idle until a power failure occurs,
and then switches from utility power to its own power
source, almost instantaneously. An on-line UPS continuously
powers the protected load from its reserves (usually lead-
acid batteries or stored kinetic energy), while
simultaneously replenishing the reserves from the AC power.

The on-line type of UPS, in addition to providing
protection against complete failure of the utility supply,
provides protection against all common power problems, and
for this reason it is also known as a power conditioner and
a line conditioner.
online ups is the one which in on position (both cases:
powersupply on&off).but in case of offline ups is on at the
time power failure.

Answer / engr.faridul alam

In case of ONLINE UPS-
when main supply is there, power is drawn from AC main
source & stored in the battery after conversion. DC power
from battery is converted to AC & supplied to LOAD all the
times (whether there is main power or not). LOAD never draws
power directly from AC mains.

In case of OFFLINE UPS-
When main AC supply is ON, LOAD gets power directly from
main supply & simultaneously battery is being charged from
main source. When there is power failure, main supply
disconnects & within few milliseconds AC supply which is
obtained from battery via converter) connects with LOAD.

Answer / sushant kumarj ena

Online UPS, it is getting power AC is converting to DC, then
the DC source stored to Battery at power supply on mode when
power fail, the DC sorce is changed to AC by inverter so
output power is having without noise.

OFFline UPS is having automatic voltage regulator, it
getting power from supply, it is regulated by AVR, then
power stored to battery so the change over time approx 2ms
to 5ms so change over noise comes.

Answer / mithilesh dwivedi

Online UPS alwaws given Constant voltage i.e.230V 50 Hz.and
what ever input like 170 v to 270V.Voltage goes through the
circuit and through the Battery in any time when AC is
present or on Backup position.

Offline UPS alwaws gives Same output what is input received
from Main. Voltage goes Without Circuit and only Battery
charging Voltage 12V DC goes to battery.When Mains is fail
then supply goes from battery backup.

Resultant On Line UPS Costly than the OFF Line UPS.

Answer / deepu

in the case of online ups,we are getting constant output voltage without any varriation ,if there is mains or not.

but in offline the output voltage is varried during the changeover time..

so online ups is the better choice for computer applications than offline...

Answer / amit kumar

On line UPS means supply will come from batteries on line
and charging also on line.



off line UPS supply will come from batteries when main line
supply fails.Batteries will charge on line.

Answer / gurumurthi

In Online UPS the main supply passes through Battery as well as inverter to the load at time.

But in Offline UPS the main supply passes direct to load & to the battery section & bypasses the inverter section. Once the mains fails the supply is feed from battery section.

Answer / sana

yes

Answer / nilesh

On line UPS means you monitor the UPS by Ethernet card from anywhere this is on line UPS
Off line UPS means you have to go near the UPS for taking all deta

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