Bradford White RE3 Service Manual page 3

Commonly Used Formulas
Watts
Amps =
Volts
Watts
Amps =
Volts x 1.732
Watts =
Amps x Volts
Volts
Ohms =
Watts
BLACK Grounded
Ungrounded
120
Neutral A B
120
120
120
208
RED BLACK
(for single phase units) Example: 4500W/240V = 18.75A
(for balanced 3 phase units) Example: 4500W/240V x 1.732 = 10.82A
Example: 18.75A x 240V = 4500W
2
Example: (240V) / 4500W = 12.8 Ohms
WHITE
GREEN
Grounding
(Neutral)
0
120
Neutral
C
120
120
208
208
RED
2
BLACK
Ungrounded
A B C
120
240
240 240
RED BLACK RED
Page 3
GENERAL INFORMATION
RED
Ungrounded
240 120
120
Neutral A
277
277
277
480
RED BLACK
GREEN
Grounding
B C
480
480
RED
3