Answer / rvg

The transformer details shows no load voltage and we can
assume about 3-4% decrease with full load. ACB with rated
voltage 690 should not be suitable for 725V. ACB's nominal
voltage should be 1.414 time the applied voltage.

Answer / mnm

Your selection is OK. Any breaker will have 110% voltage
withstand capability. Only thing is interruption capability
reduces, which is not relevent on no-load. On load, the
voltage of the transformer will reduce by nearly 6%, due to
impedance, making it just suitable.

Answer / praveen kumar gupta

ACB is not suitable as transfomer secondary voltage level
is higher than ACB voltage level which cause insulation
failure of the ACB and cause of flash.

Answer / loke

We can agree with Mr.Mnm because actually the rating of
breaker ia 690v and it will be having with stand capacity of
+_10% so it can with stand upto 765v & also check out with
the impedence it would be around 6-9% from that also you can
check secondary voltage of t/f.

Answer / joe

there wil be no effect because in transformer the input and
the output is difference due to the coil winding

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How does a diesel generator works?

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what is rated voltage?

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why rating in KVA and KVAR?

4 Answers  

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