In a 3 phase,400v,4 wire system, 2 incandescent lamps, one having 230v,100w and

In a 3 phase,400v,4 wire system, 2 incandescent lamps, one
having 230v,100w and the other 230v,200w are connected between
r phase- neutral and y phase-neutral respectively. If neutral
wire breaks which lamp will fuse first and why?

Question Posted / lata

3 Answers
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In a 3 phase,400v,4 wire system, 2 incandescent lamps, one having 230v,100w and the other 230v,200w..

Answer / awdhesh

When neutral disconeted bulb are in series so ckt current is same but voltage drop is diffrent.vlt drop is propesanl to R so 100W lamp R is more with respect to 200W. 100 W lamp fuse first.

Is This Answer Correct ?

37 Yes

5 No

In a 3 phase,400v,4 wire system, 2 incandescent lamps, one having 230v,100w and the other 230v,200w..

Answer / velmurugan

100W lamp will fail first, Although the voltage across 100 w
lamp will be higher (293V), but it will fail because of
effective current (0.489A) which is more than the 100 w
lamp normal current (0.4A). Increase in current cause more
heat and heating element will fail.

Is This Answer Correct ?

6 Yes

3 No

In a 3 phase,400v,4 wire system, 2 incandescent lamps, one having 230v,100w and the other 230v,200w..

Answer / harsh

It might be .... the Phase issue ...
Phase R is Generally 120 angle ahead of phase Y...

Lets suppose A complax situation here..
We are now going to add an another Load of 300w in phase B
With same voltage drop..
At that time also 100 watt bulb would b fuse First...

Is This Answer Correct ?

0 Yes

7 No

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