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Question
Difference between online and offline UPS?
 Question Submitted By :: Electrical-Engineering
I also faced this Question!!     Answer Posted By  
 
Answer
# 1
In Online ups output supply is continuously from battery to
inverter then load but in offline ups battery and inverter
comes in picture when power gets fail.
 
Is This Answer Correct ?    54 Yes 8 No
Dolnarayan Patel
 
Answer
# 2
IN ONLINE UPS THERE IS A DOUBLE CONVERSION AC TO DC THEN DC
TO AC.SO THERE IS NO INTERRUPTION IN ONLINE UPS WHEN MAIN
SUPPLY FAILS.BUT IN OFF LINE UPS THERE IS ONLY ONE
CONVERSION AT A TIME EITHER AC TO DC OR DC TO AC WHICH
SWITCH OVER WHEN CAHNGE OVER DONE.
 
Is This Answer Correct ?    27 Yes 4 No
Pawan Pratap
 
 
 
Answer
# 3
In online UPS, supply to the load is continuous.In offline
UPS there is an interruption of suplly to load for a small
time while switching from i/p supply system to battery.
 
Is This Answer Correct ?    27 Yes 8 No
Swathi
 
Answer
# 4
In Online ups output supply is continuously from battery to
inverter then load but in offline ups battery and inverter
comes in picture when power gets fail.
 
Is This Answer Correct ?    14 Yes 5 No
Srinivas..m
 
Answer
# 5
when the ups system is in floating mode it is said to
online.when supply is off and if the UPS is feeding load
the it a offline UPS
 
Is This Answer Correct ?    32 Yes 28 No
Mustafa
 
Answer
# 6
online ups : in this process if the ip volt is vary frm
170vto 280v, its op will be always const as 230v

offline ups: in this process if any ip volt means its
simply direct us the same volt
 
Is This Answer Correct ?    5 Yes 3 No
Rajan Babu
 
Answer
# 7
In an online UPS there is AC to DC conversion using a rectifier, DC to DC boosting and finally DC to AC conversion simultaneously at the same time. Online UPS is in operation and supply power to the load with mains power on.

An offline UPS charges the batteries when mains power is on and supplies power to the load when mains fail.
 
Is This Answer Correct ?    1 Yes 1 No
Castelino Nithin Francis
 
Answer
# 8
Online UPS is- the ups is connected to power supply and the
equipment is connected to the UPS.i.e ups does 2 works
here,they are:1) give the supply to the equipment.2) charge
the batteries in the UPS from the supply. this is online ups.

offline ups: the supply is connected to the ups and the same
supply is connected to equipment,i.e the supply charges the
ups and also the equipment. then if there is a failure in
the power supply then we disconnect the equipment from
supply and connect it to ups.this is the disadvantage of
this so we shifted to online UPS long ago.

example for the online UPS is: the ups we use for the
computers in our home
 
Is This Answer Correct ?    9 Yes 12 No
Thuranga
 
Answer
# 9
When ups taking load by equipments,thattimes its onlinebut
but equi.taking suply from bypass line that time ups is
ofline.
 
Is This Answer Correct ?    4 Yes 9 No
Amit.sonmale
 
Answer
# 10
On line UPS connection to the user is automqatically, so
there is an electical interlock between it and power
network . The logic of this inter lock is when power
network is on the UPS is diconnecterd from the user and
when power network is off, the UPS become connecterd to the
user.

In addition, on line UPS are used supply some important
equipment in some applications permanently such as process
computer, PLC or realys in industrial plants.

Off line UPS connection to the user is manually. So when
the power network is off, somebody has to connect the UPS
to the user by closing a breaker or contactor.
 
Is This Answer Correct ?    13 Yes 33 No
Saeid
 

 
 
 
Other Electrical Engineering Interview Questions
 
  Question Asked @ Answers
 
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