GENERAL MOTOR INFORMATION
MOTOR MODIFICATIONS
SECTION 8
PAGE X-1
GENERAL MOTOR INFORMATION:
ELECTRIC MOTORS FALL INTO TWO MAJOR CATEGORIES, A.C.
AND D.C.. SINCE D.C. MOTORS ARE FURNISHED BY FEDERAL ONLY ON SPECIAL ORDER, WE
WILL LIMIT THE FOLLOWING DATA TO A.C. MOTORS.
A.C. MOTORS FALL INTO TWO CATEGORIES, SINGLE-PHASE
AND THREE-PHASE. SINGLE-PHASE MOTORS ARE BUILT WITH ONE CONTINUOUS STATOR
WINDING AND, THEREFORE, THE MAGNETIC FIELD CREATED DOES NOT REVOLVE AS IT DOES
IN A THREE-PHASE MOTOR. FOR THIS REASON, SINGLE-PHASE MOTORS REQUIRE AN
AUXILIARY METHOD OF STARTING. SINGLE-PHASE MOTORS OFFERED BY FEDERAL ARE OF THE CAPACITOR-START
TYPE WHICH INDICATES THAT A CAPACITOR IS USED IN SERIES WITH A SEPARATE STARTING
WINDING (THE CAPACITOR IMPROVES THE STARTING TORQUE); WHEN A SUFFICIENT SPEED IS
REACHED THE CAPACITOR AND STARTING WINDING ARE CUT OUT BY A CENTRIFUGAL SWITCH.
THREE-PHASE CURRENT CONSISTS OF THREE ALTERNATING CURRENTS
OF EQUAL FREQUENCY AND AMPLITUDE, BUT BEING PHASED EXACTLY 1/3RD OF A PERIOD
APART. THREE-PHASE CURRENT REQUIRES THREE WIRES, WHILE SINGLE-PHASE CURRENT
REQUIRES TWO. HOWEVER, THREE TIMES AS MUCH POWER IS DISTRIBUTED OVER THE
THREE-PHASE LINES THAN OVER THE SINGLE-PHASE LINES, MAKING THREE-PHASE CURRENT
MORE ECONOMICAL ABOVE THE 1/2 HP LEVEL. THE PHASING OF THREE-PHASE CURRENT
ESTABLISHES A ROTATING MAGNETIC FIELD IN THE MOTOR STATOR, WHICH INDUCES A
MAGNETIC FIELD IN THE ROTOR, THUS DRAGGING THE ROTOR AROUND.
THREE-PHASE MOTORS OFFERED BY FEDERAL (ON STANDARD
EQUIPMENT) ARE OF THE SQUIRREL-CAGE TYPE, WHICH MEANS THAT THE ROTOR
CONSTRUCTION RESEMBLES A SQUIRREL CAGE, BEING COMPOSED OF PARALLEL AXIAL BARS.
THE SPEED OF A SQUIRREL-CAGE MOTOR DEPENDS ON THE FREQUENCY OF CURRENT SUPPLIED
AND THE NUMBER OF POLES WIRED INTO THE MOTOR. TWO-POLE MOTORS (3600 RPM) ARE THE
FASTEST (4-POLE - 1800 RPM; 6-POLE - 1200 RPM; 8-POLE - 900 RPM). THE ACTUAL
RUNNING SPEEDS ARE SOMEWHAT LESS THAN THE SYNCHRONOUS SPEEDS STATED ABOVE; THIS
DIFFERENCE IS CALLED SLIP. SLIP OCCURS BECAUSE THE ROTATING MAGNETIC
FIELD OF THE STATOR MUST CONSTANTLY OVERTAKEN AND BE CUT BY THE ROTOR
WINDINGS.
SQUIRREL-CAGE MOTOR DEFINITIONS:
EFFICIENCY - RATIO OF POWER OUT TO POWER IN, EXPRESSED
AS A PERCENTAGE.
POWER FACTOR - RATIO OF REAL POWER TO APPARENT
POWER, EXPRESSED A PERCENTAGE.
ROTATION - DIRECTION OF ROTATION OF THE ROTOR AND
SHAFT (MAY BE REVERSED BY INTERCHANGING ANY TWO MOTOR LEADS).
TORQUE - TURNING EFFECT OF A MOTOR, EXPRESSED IN
FOOT-POUNDS.
HORSEPOWER - RATE OF DOING WORK ( 1 HP EQUALS 33,000
FOOT-POUNDS PER MINUTE).
FULL LOAD TORQUE - THE STEADY CONSTANT TORQUE AT RATED LOAD.
STARTING TORQUE - ADDITIONAL TORQUE REQUIRED TO START
THE LOAD ( ABOUT 210% OF FULL LOAD TORQUE).
BREAKDOWN TORQUE - ADDITIONAL TORQUE CAPACITY TO PREVENT STALLING FROM
OVERLOADS ( ABOUT 270% OF FULL LOAD TORQUE).
SERVICE FACTOR - MULTIPLIER WHICH APPLIED TO HP
RATING INDICATES PERMISSIBLE OVERLOADING (VARIES FROM APPROX. 1.25 FOR I HP
MOTORS TO 1.15 FOR 3 HP MOTORS AND LARGER.
NEMA DESIGN DESIGNATION - STD. FEDERAL SQUIRREL-CAGE MOTORS ARE NEMA
DESIGN B, INDICATING NORMAL STARTING TORQUE, HIGH OVERLOAD TORQUE AND LOWER
STARTING CURRENT, FOR GENERAL PURPOSE APPLICATIONS.
INSULATION CLASS:
CURRENT NEMA FRAME MOTORS ARE FURNISHED WITH CLASS B INSULATION
FOR TEMPERATURE RISE RATINGS OF APPROXIMATELY 70ºC.
STANDARD OPERATING CONDITIONS:
STANDARD SQUIRREL CAGE INDUCTION MOTORS ARE DESIGNED TO OPERATE
SUCCESSFULLY UNDER THE FOLLOWING CONDITIONS:
1. AMBIENT (ROOM) TEMPERATURE NOT EXCEEDING 40ºC (104ºF).
2. A VARIATION IN VOLTAGE OF NOT MORE THAN 10% PLUS OR MINUS THE NAMEPLATE
RATING.
3. A VARIATION IN FREQUENCY (CYCLES OR HERTZ) OF NOT MORE THAN 5% ABOVE OR BELOW
THE NAMEPLATE RATING.
4. AN ALTITUDE NOT EXCEEDING 3300 FEET.
5. ATMOSPHERIC CONDITIONS (DUST, MOISTURE, FUMES) WHICH WILL NOT SERIOUSLY
INTERFERE WITH VENTILATION.
MOTOR ENCLOSURES:
1. DRIP-PROOF - AN OPEN MOTOR SO CONSTRUCTED THAT DROPS
FALLING AT ANY ANGLE NOT GREATER THAN 15º FROM THE VERTICAL CANNOT ENTER.
2. TOTALLY ENCLOSED - PREVENTS FREE EXCHANGE OF AIR BETWEEN INSIDE AND
OUTSIDE OF MOTOR (NOT AIRTIGHT).
3. TOTALLY ENCLOSED FAN-COOLED - TOTALLY ENCLOSED WITH A FAN TO BLOW
COOLING AIR ACROSS THE EXTERNAL FRAME.
4. EXPLOSION-PROOF - A TOTALLY ENCLOSED MOTOR DESIGNED TO WITHSTAND AN
EXPLOSION WITHIN AND TO PREVENT IGNITION OF GAS SURROUNDING IT.

MOTOR AND CONTROL MODIFICATIONS
SECTION 8
PAGE X-2
50 CYCLE MOTORS
TO PRICE A PUMP WITH A 50 CYCLE MOTOR (STANDARD 50 CYCLE VOLTAGE), USE THE 60
CYCLE PRICE OF THE NEXT HIGHER H.P. AT THE REQUIRED R.P.M. THE OPERATING SPEED
AT 50 CYCLES WILL BE 5/6 OF THE 60 CYCLE SPEED. DERATE PERFORMANCE CURVES
ACCORDINGLY. STANDARD 50 CYCLE VOLTAGES ARE 190/380V, 200/400V, 208/416V AND
220/440V. FOR OTHER 50 CYCLE VOLTAGES, CONSULT ABC ELECTRIC CORP.
SPLASH-PROOF MOTORS
CURRENT DRIP-PROOF MOTORS INCORPORATE MOST OF THE FEATURES OF THE OLD
SPLASH-PROOF DESIGN AND CAN BE USED FOR MOST APPLICATIONS CALLING FOR
SPLASH-PROOF HOUSINGS.
POWER CORD AND PLUG
Power cord and plug (3-wire plug with ground) is furnished as standard equipment
on 115V motors on the following units: MC-1, MMC-1, MCH and ALTV. To add an
8-Ft. Power cord and plug for 1/4, 1/3 and 1/2 HP motors OPERATING at 230V
(or 115V on units not enumerated above) add ---
$135
TOTALLY ENCLOSED AND EXPLOSION-PROOF MOTORS SEE SECTION 8,
PAGE X-3
MISCELLANEOUS MODIFICATIONS
CONSULT ABC ELECTRIC CORP FOR MODIFICATIONS SHOWN BELOW, OR FOR OTHER
NON-STANDARD FEATURES:
HIGH ALTITUDE MOTORS.
SPECIAL SHAFT EXTENSIONS.
HIGH AMBIENT TEMP MOTORS.
GUARDED MOTORS, SCREENED OPENINGS.
NON-STANDARD VOLTAGES.
SPACE HEATERS IN MOTORS.
EXTRA LONG LEADS.
TEMPERATURE SENSORS IN WINDINGS.
SPECIAL NAMEPLATES.
STAR-DELTA MOTORS.
FACTORY CHOICE BRANDS
FEDERAL RESERVES THE RIGHT TO FURNISH FACTORY CHOICE BRAND MOTORS AND CONTROLS
AS SHOWN BELOW. IF NON-STANDARD BRANDS ARE REQUIRED, ADD THE FOLLOWING
PERCENTAGES TO THE LIST PRICES OF THE MOTORS OR CONTROLS:
MAGNETIC STARTERS, COMBINATION STARTERS, D&T PANELS
--- ADD 40%
FRACTIONAL FRAME MOTORS --- ADD 55%
INTEGRAL FRAME MOTORS --- ADD 35%
STANDARD VOLTAGES AND SUPPLIERS
STANDARD SUPPLIERS SHOWN ARE FOR GENERAL INFORMATION
ONLY AND ARE SUBJECT TO CHANGE WITHOUT NOTICE: