Answer / thowsif_emerson_csm team

A UPS consist of 3 parts ,inverter ,charger,and AVR
(voltage regulator).when mains is present a UPS provides
supply to computer in regulated mode using inbuilt AVR ,and
simultaneously charges the batteries.
when mains fails it changes over to inverter mode using an
electromechanical relay (The changeover time is as fast as
4 milli secs in offline UPS).The charging current of ups is
normally 1amps to max 6 amps

in case of inverter when mains is present it bypasses what
ever comes in betweeen 100-280 volt(a typical setting in
all reputed brands)
when mains fails it changes over to inverter mode and
change over time as high as 200 mill secs.
The charging current is high minimum 8 amps and can go upto
20 amps

there are some companies which make special kind of
inverter under the name of home ups.These are ordinary
inverter with two difference ,one----the change over is
made very fast upto 10 millisecs,
second input mains range is reduced to 190-250 v A/C,so
that if it goes below 190 volts it goes to batt mode and
same is te case when input exceeds 250.These kind of home
UPS are succes ful only upto one PC ,with higher number of
PCs the complaint of rebooting whem mains fails increases
drastically,hence never recommended.

Answer / yvb

Inverter is Part of UPS. May be above answer given by an IT
student.
mains + rectifier + battery charger + batteries + inverter
= UPS ( A static switch also includes in industrial ups.)
UN INTERRUPTED SUPPLY means absolutely no inturruption.
its hard to sence intruption.
Inverter also consists same parts but less
capacity.changeover is not fine.we can sence the
intrruption.

Answer / mohit.k.k

what ever above said is right but technically inverter is
that which convert d.c to a.c and its is a part of ups
(uninterupted power supply)

Answer / vj

whatever mr.Thowsif_emerson_csm has explained is good....
i wud like to know some answers on distribution side like why transformer rating is given in kva?
what happens if reactive increased or decreased?
what is the exact amount of reactive power should be maintained?
and wht to do for that?

WHY DOES NEUTRAL DO NOT CARRY EVEN THOUGH IT CARRIES RETURN CURRENT?

3 Answers  

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bit confused - am i correct in thinking that to determine line to line voltage in a star config 110v 3 phase 4 wire distribution system i would use a voltmeter? I have a circuit configured as an unbalanced load, consisting of three incandescent lamps (1x40w, 1x60w, 1x100w - all 110v rated)connected in a star configuration to a 110v 3 phase 4 wire distribution system. I want to find out what types of meters i would use to obtain: a) each line to line voltage b) the line to neutral voltage across each load c) current flowing in each line and load d) current flowing in the neutral conductor e) power supplied to the loads im assuming i would be using ammeters in series along each line and voltmeters in parallel across each line to neutral? Also how could i predict these meter readings before taking them and with which formulae? Any help would be greatly appreciated A.

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1 Answers  

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