Why we use less dia. fuse and conductors at H.T. side, although we use higher dia. cables on L.t. side?

Answer Posted / al amaan

The size of the cable(Conductor) is choosed depends on the current value
For Example In 1000 KVA,11 KV/433 V Step down Transformer
Formula for calculate Power in KVA; P=√3*V*I
Current Formula; I=P/(V*√3)
Current in H.T side; ; I=1000/(11*√3)
I= 5.25 A
Current in L.T side; I=1000/(433*√3)
I= 133 A
From that the current in L.T side is higher than the H.T side So we use Higher dia cables in L.T side

Is This Answer Correct ?    1 Yes 0 No



Post New Answer       View All Answers


Please Help Members By Posting Answers For Below Questions

what is the minimum winding resistance of 30hp compressor, to run or to switch on

1410


can we do the star delta connection of capacitor for 3- phase motor starter.

1548


Why the dc voltage drop during starting of emergency lube oil pump? The Voltage drop from 135kv to 125 kv for one min. before re-establish to 135kv?

1802


any one guide me to reduce the power factor of diesel Generator from 0.97 Leg to 0.8 Leg.with out any change in my load.

1222


How to calculate cable size by using load.?? Any formula...

914






How to calculate no of EARTH PIT? Describe the formula as per IS standard?

3197


What is the comparison of PILC and XLPE cable

1518


detailed procedure how we calculate cost for pcc m10 and rcc m20 including centering and labour excluding steel/ iron

2628


What is the function of NGR for the parallel operation of alternator? whats happen when different rating of alternator are running with parallel?

2501


What are the Formula of computing Back up Time of 500kVA UPS with 4 Battery Banks, each bank composed of 43 pcs of Batteries 12V150Ah. How to compute the Back up Time of UPS? We have also 3X500kVA UPS running in Parallel same composition as I write above.

908


at work we have a 3 phase motor but on testing one phase isnt getting a reading. it runs 24 hours a day all week. stops and starts well no noise or heating. the phase isnt down to earth.is it just a bad meter reading or not? phases one and three came up with a resistance reading of 0.4 but phase 2 couldnt get anything shows up as open circuit.

1188


what r the checklist while installing a 380 kva DG set

3330


how to calculate the breaking capacity of different breakers.

1705


Explain what is clipper and clamper circuits?

704


how will we calculate the copper wire load..

1460