how to caluclate cable size by Amps

Answer Posted / s bagchi

Step1: convert the kva or kw load into amps by dividing
with the respective voltage & pf in case of kw.
Step2: refer a cable catalogue & derate the current
considering temperature rating factor & group rating factor.
Step3: select a cable size considering the derated current.

at first you need to calculate the min cable size in case
of ht cables considering short time current & the fault
clearing time of the upstream breaker.

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