A.O. Smith ST1302 - Page 49

Pump Motors 47
Level 2 A.O.Smith
MOTOR REPLACEMENT REMINDERS
A. If possible, isolate the cause of failure so that:
1. There will be confidence that a similar
replacement motor will have an accept-
able service life.
2. If external conditions (moisture, low volt-
age, etc.) contributed to the failure, they
may be corrected.
B. Match the mechanical and electrical charac-
teristics of the original and replacement
motors.
1. Mounting
This will include the end frame, shaft
extension and base (if so equipped). The
nameplate will provide some or all of the
needed information in the section for
frame size (FR).
2. Electrical
Determine operating voltage, phase, max
amps and hertz or cycles.
3. Horsepower
Multiply nameplate horsepower times the
service factor to find total horsepower.
The total horsepower of the replacement
motor must equal or exceed the original
motor.
4. Model Number
Each motor has a series of numbers
and/or letters which designate one specif-
ic design. This number alone is sufficient
for the manufacturer to cross reference
the motor for replacement. If this num-
ber was crossed previously, it may be on a
published list. Don't rely on the number
alone. A difference of one number or let-
ter means a different motor. The model
number may contain some descriptive
information, but by itself does not enable
someone in the field to select a replace-
ment.
Motor
Replacement
Reminder s