hp : the measure of rate of work .one horse power is
equivalent to lifting 33,000 pounds to a height one afoot
in one minutes .the horse power of motor is expressed a
function of torque and rpm for motor the following
approximate formula may be used

hp =txrpm /5250
t-torque (in-ib.ft),rpm- revolutin per minute
hp -horse power

kw : the watts is relatively small unit of power the kilo
watts (kw) 1,000 watts is use where large unit of power
measurement are desirable

Horsepower is a north american standard for specifying
motors. KW is the European standard.

Low Voltage motors listed in KW will normally have 3
phase / 50 Hertz as there power supply.

Low Voltage motors listed in Horsepower will normally have
3 phase / 60 hertz as the power supply.

Unless the Engineers are mixing standards when specifying
the motor.

It should be noted that the frequency of the supply power
will affect the RPMs of the motor. In north america 3/60
power the normal nominal RPMS are 3600, 1800, 1200, 900,
while in Europe (3/50) the normal nominal RPMS are 3000,
1500, 1000, 750.

Hello friends, Can anyone explain the concept of zones in
Bus bar protection and how can we differentiate the main
zone and check zone in Bus bar protection