Bradford White ERE240 Service Manual page 3

Commonly Used Formulas
Watts
Amps =
Volts
Watts
Amps =
Volts x 1.732
Watts =
Amps x Volts
2
Volts
Ohms =
Watts
Common Service Wire Configurations
WHITE
BLACK
Grounded
(Neutral)
Ungrounded
THE WATER HEATER MUST BE WELL GROUNDED. USE THE GREEN GROUND SCREW PROVIDED AT
THE ELECTRICAL CONNECTION POINT FOR CONNECTING A GROUND WIRE.
(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
GREEN
Grounding
WARNING
3
INFORMATION
RED
BLACK
Ungrounded
Ungrounded
240
120
GREEN
Grounding
120
3