ALTERNATING AND DIRECT CURRENT FORMULAE

TO FIND	DIRECT CURRENT	ALTERNATING CURRENT
TO FIND	DIRECT CURRENT	SINGLE PHASE	2 PHASE, 4 WIRE*	THREE PHASE
AMPERES ( I ) WHEN HORSEPOWER ( hp ) IS KNOWN	746 x hp I = ------------ E x eff	746 x hp I = -------------- E x eff x pf	746 x hp I = ---------------- 2 x E x eff x pf	746 x hp I = ---------------- 1.73 x E x eff x pf
AMPERES ( I ) WHEN KILOWATTS (kW) IS KNOWN	1000 x kW I = ------------- E	1000 x kw I = ------------- E x pf	1000 x kw I = -------------- 2 x E x pf	1000 x kw I = -------------- 1.73 x E x pf
AMPERES ( I ) WHEN KILOVOLT-AMPERES (kVA ) IS KNOWN	Not Applicable	1000 x kva I = -------------- E	1000 x kva I = -------------- 2 x E	1000 x kva I = -------------- 1.73 x E
KILOWATTS ( kW ) INPUT	I x E kw = ---------- 1000	I x E x pf kw = ----------- 1000	I x E x 2 x pf kw = -------------- 1000	I x E x 1.73 x pf kw = ------------- 1000
KILOVOLT-AMPERES (kVA )	Not Applicable	I x E kva = ---------- 1000	2 x I x E kva = ------------ 1000	1.73 x I x E kva = ------------ 1000
HORESPOWER ( hp ) OUTPUT	I x E x eff hp = ------------ 746	I x E x eff x pf hp = --------------- 746	I x E x 2 x eff x pf hp = ---------------- 746	I x E x 1.73 x eff x pf hp = ----------------- 746

* For two Ø, three wire, balanced circuits the I in the common conductor = 1.41 x that in either of the other two. I = amperes, E = Volts ( line to line ), pf = Power Factor (in decimals), eff = Efficiency (in decimals), kw = Kilowatt Input, kva = Kilovolt-Ampere Input, hp = Horsepower Output