Answer / srikanthgss

I think ... since its a 5 MVA transformer , you can have a
unity pf load of 5kw or 4.5mw at 0.9 pf lag or 4.0mw load at
0.8 pf lag .

{ P=VIcos@
Given VI= 5MVA

=> at 0.9pf = 5*0.9=4.5MW
at 0.8pf = 5*0.8=4.0MW
..... etc .
}

Answer / javad

Transformer have an interesting characteristics ie
You can Load the transformer around 20 % of Full load to
around 120% of full load without any problems(At that time
efficiency lie between 75 to 95 %).But maximum
efficiency will give when copper loss equal to core loss that
is around 80 to 85 % of full load.just see load vs efficiency
curve, then u ll b more clear.

Answer / dharmendra

(
Load calculation for 3 phase ac motor



A = 1000 × P(kW) / (√3 × PF × VL-L(V)

Answer / k.sri405

MVA is the apparent power means combination of active and
reactive power. Load means active power so 5 MVA capacity
means we can load this transformer below 5 mw.if there is a
completely resistive load than it may be loaded upto 5 mw
but practically it is not possible.

Answer / ramesh

KW = KVA x pf
1mva=1000kva
kva*0.8= kw
5*0.8=4kw
1kw= 1000W
4=1000*4=4000kw
5mva= 4mw or4000w
--RAMESH

Answer / addicted to know electrical

Load means current,not Mw(power).So,by looking at
P=VI*p.f....
Since i is load which is always variable....the power drawn
from the transformer will always vary......and hence it is
not inour hand how much load shall be given to the
transformer but the efficiency will be max. when load is
equal to iron loss divided by square of secondary
resistance.

Answer / guest

50ohm

Why we does earthing for transformer neutral point

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