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Motor Operating and Maintenance Manual with Warranty

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XP Hazardous Location Motor Operating and Maintenance Manual with Warranty

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Gear Reducer Operating and Maintenance Manual with Warranty

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Attention Food Processors  – Read our white paper on why Sanifan® motors should be part of your FSMA preventative plan implementation

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Glossary

AC:  Alternating current.







AC Motors:   a motor operating on AC. The two general types are induction and synchronous







Air Gap:  space between the rotating (rotor) and stationary (stator) member of an electric motor







Altitude:  the height above sea level at which a motor will be operating;  NEMA standards state an altitude exceeding 3,300 ft. (1,000 meters) requires derating of a motor due to reduced cooling ability







Ambient Temperature:  the temperature of the surrounding air which comes into contact with the motor. The standard NEMA rating for ambient temperature is not to exceed 40°C / 104°F







Axial Thrust: the force or load that is applied to the motor shaft in a direction parallel to the axis of the shaft such as from a fan or pump







Brake:  an external device that brings a running motor to a standstill and/or holds a load







Braking Torque:  the torque required to bring a motor to a standstill









Breakdown Torque:  the maximum torque a motor will develop at rated voltage without a relatively abrupt drop or loss in speed







“C” Face / Flange:  a NEMA standard flange used with close coupled pumps, speed reducers, and in similar applications where the mounting holes in the flange are threaded to receive bolts, a “C” face is used where a pump or similar item is to be overhung on the motor









Conduit Box (Junction Box): the metal container where a motor’s winding leads are attached to leads connecting to the power supply







Constant HP: A designation for variable or adjustable speed motors used for loads requiring the same amount of HP regardless of their motor speed during normal operation







Core:  the iron portion of the stator and rotor made up of  laminated electric steel;  the stator and rotor cores are concentric and separated by an air gap with the rotor core being the smaller of the two and inside to the stator core







Coupling: the mechanical connector joining a motor shaft to the equipment to be driven







Current: the flow of electrical charge measured in amps (amperes)







Cycles Per Second (Hertz):  The frequency of a power source. 60 Hz ( cycles per second) AC power is common throughout the US and 50 Hz is common in foreign countries







“D” Flange:  an endbell with holes for through bolts in the flange;  primarily used for mounting a motor on a gear reducer;  standardized for frames 143T through 445T; “D” flanges are not threaded and bolt holes extend beyond the motor frame







Drive End (DE):  The end of the motor with the output shaft



Dual Voltage:  a motor may be capable of operating on two different voltages depending on its construction and connections







Dynamometer: A device which loads the motor to measure output torque and speed accurately by providing a calibrated dynamic load; the tool is helpful in testing motors for nameplate information and for measuring efficiency







Efficiency: the efficiency of a motor is the ratio of mechanical output to electrical input;  efficiency represents the effectiveness with which a motor converts electrical energy into mechanical energy; NEMA has codes correlating to specific nominal efficiencies







Enclosure: the housing frame of a motor







Endbell: the motor housing which supports the bearing and acts as a protective guard for the electrical and rotating parts inside a motor; also called the end bracket or end shield







Explosion Proof Enclosure: a totally enclosed motor enclosure constructed to withstand and contain an internal explosion; the enclosure prevents the ignition or explosion of gas or vapor surrounding  the motor enclosure;  explosion proof  enclosed motors are listed with Underwriter’s Laboratories (UL)







Flange:  Mounting endbell with special rabbets and bolt holes for mounting equipment as pumps and gear boxes to the motor or for overhanging the motor on the driven machine







Frame:  the supporting structure for the stator parts of an AC motor; the frame determines mounting dimensions







Frame Size:  refers to the set of NEMA established motor dimensions, including critical mounting dimensions;  48 and 56 frame motors are fractional HP sizes , but can exceed 1HP; 143T to 449T are c integral HP AC motors;  5000 series and higher are large motors



 



Full Load Current:  the greatest current that a circuit or motor is designed to carry under specified conditions







Full Load Torque: That torque of a motor necessary to produce its rated HP at full-load speed ; also referred to as running torque







Hertz (Hz): One cycle per second (as in 60 or 50 cycles per second)







Horsepower (HP):  a foot per second unit of power, equal to 550 foot-pounds per second (equivalent to 746 watts); the horsepower of a motor is expressed as a function of torque and RPM







Inductance: the characteristic of an electric circuit by which varying current in it produces a varying magnetic field causing voltage in the same circuit or in a nearby circuit







Induction Motor: an induction motor is an AC motor in which the winding on the stator is connected to the power source and a squirrel-cage secondary winding on the rotor carries the induced current; there is no physical electrical connection to the secondary winding, its current is induced







Inertial Load: a load which tends to cause the motor shaft to continue to rotate after the power has been removed







Insulator: material which tends to resist the flow of electric current (paper, glass, etc.) in a motor; the insulation separates the various electrical components from one another and protects itself and the electrical components from contaminants and other destructive forces







Insulation Class: motor insulation is classified by the temperature ranges at which it can operate for a sustained period of time. There are four common classes:A, B, F and H.







Intermittent Duty: requirement of services that demands operation for alternate intervals of (1) load and no load; or (2) load and rest; or (3) load, no load and rest; such alternate intervals being definitely specified







Inverter: an electronic device that converts fixed voltage to variable frequency and voltage; an inverter enables the user to electrically vary the speed of an AC motor







Junction Box (Conduit Box): the metal container where a motor’s winding leads are attached to leads connecting to the power supply







Kilowatt (kW): as the watt is a relatively small unit of power, the kilowatt (kW) 1,000 watt is routinely used when larger units of power measurements is desirable







Laminations: steel portion of the rotor and stator cores made up of a series of thin sheets which are stacked and fastened together by cleats, rivets or welds; laminations are used instead of a solid piece in order to reduce eddy-current losses







Locked Rotor Current:  steady state current taken from the line with the rotor at standstill at rated voltage and frequency; current observed when starting the motor and load







Locked Rotor Torque: minimum torque that a motor will develop at rest for all angular positions of the rotor with rated voltage applied at rated frequency







Loss:  a motor converts electrical energy into mechanical energy and encounters loss; loss is the energy that is put into a motor and not transformed to usable power, the energy is converted into heat causing the temperature of the windings and other motor parts to rise







Magnetic Polarity: principle of a winding that adjacent poles must be wound to give opposite magnetic polarity







Nameplate: plate or diagram on the outside of the motor describing its dimensional standard, frame, HP, voltage, RPM, efficiency, design, enclosure, etc.







Opposite Drive End (ODE) : The end of the motor opposite to the output shaft end.



Phase: the space relationship of winding and changing values of the recurring cycles of AC voltage and currents. Due to the positioning of the windings, the various voltages and currents will not be similar in all aspects at any given time; each winding will lead or lag another voltage in time and each current will lead or lag another current in time; the most common power supplies are either single (1 ) or three phase (3)







Pull-Up Torque: minimum torque developed by an AC motor during the period of acceleration from zero to the speed at which breakdown occurs.







RTD (Resistance Thermal Detectors):  1) a Winding RTD is a resistance device used to measure temperature change in the motor windings to detect a possible overheating condition, these detectors are embedded into the winding slot and their resistance varies with the temperature; 2) a Bearing RTD is a probe used to measure bearing temperature to detect an overheating condition, the RTD’s resistance varies with the temperature of the bearings







Resistance:  degree of obstacle presented by a material to the flow of electric current ; measured in ohms







Rotating Magnetic Field: force created by the stator once power is applied to causing the rotor to turn







Rotor: rotating member of an induction motor made up of stacked laminations; the shaft runs through the center and a squirrel-cage holds the laminations together and act as a conductor for the induced magnetic field







Service Factor: 1) When used on a motor nameplate, a number which indicates how much above the nameplate rating a motor can be loaded without causing serious degradation; 2) when applied to motors or gearmotors, a figure of merit which is used to adjust measured loads in an attempt to compensate for conditions which are difficult to measure or define; typically, measured loads are multiplied by service factors (experience factors) and the result in an equivalent required torque rating of a motor or gear motor







Short Circuit: defect in a winding which causes part of the normal electrical circuit to be bypassed; frequently results in reducing the resistance causing the winding to overheat and burnout







Slip:   the difference between the speed of the rotating magnetic field which is always synchronous and the rotor in an asynchronous induction motor; expressed as a percentage of a synchronous speed; slip generally increases with increase torque







Space Heater:  small resistance heater units mounted in a motor energized during motor shutdown to prevent moisture condensation on the motor winding





Starting Current:  amount of current drawn at the instant a motor is energized, in most cases much higher than that required for running; same as locked rotor current







Starting Torque:   torque or twisting force delivered by a motor at the instant it is energized; starting torque is often higher than rated running or full load torque







Stator: the part of an AC induction motor’s magnetic structure which does not rotate usually containing the primary winding; the stator is made up of laminations with a large hole in the center in which the rotor can turn; there are slots in the stator in which the winding for the coils are inserted







“T” Frame:   NEMA designation identifying an AC induction motor frame







Tachometer:  small generator normally used as a rotational speed sensing device; tachometers are typically attached to the output shaft of AC inverter motors







Temperature Rise: some of the electrical energy losses inherent in motors are converted to heat causing motor parts to heat up when the motor is running; the heated parts are at a higher temperature than the air surrounding them thereby causing a rise above room (ambient) temperature





Thermistor: semiconductor used to measure temperature; can be attached to an alarm or meter to detect motor overheating







Thermostat: Thermally sensitive switch applied directly to the motor’s winding which senses widing temperature and automatically break the circuit at overheating







Torque: turning force delivered by a motor or gear motor usually expressed in lbs ft



 



Totally Enclosed Blower Cooled Enclosure (TEBC):
  a separate blower motor built into the motor provides a constant flow of cooling air over the motor at all speeds; this type of cooling option is suggested for all inverter-driven motors with turndown ratios to 10:1. As the blower motor requires its own source of power, separate wiring is included and brought out through the motor’s main motor junction box







Totally Enclosed Compressed Air Cooled Enclosure (TECAC): compressed air is passed through the motor at low pressure; this option provides for a TENV-type enclosure with no external fan in areas or environments or areas which cannot tolerate the air flow from a fan







Totally Enclosed Fan Cooled Enclosure (TEFC): a fan attached to the rear end of the motor shaft blows cooling air over the body of the motor; note that air flow is dependent on shaft speed







Totally Enclosed Non-Ventilated Enclosure (TENV): no provisions for external cooling to the enclosing parts; the motor is cooled by heat radiation from the exterior surfaces to the surrounding atmosphere







Totally-Enclosed Liquid Cooled Enclosure (TELC): 
an efficient cooling method by which cooling liquid, typically water, is circulated through a special cooling jacket built into the motor







UL (Underwriter’s Laboratory): independent testing organization which examines and tests devices, systems and materials with particular references to life, fire and casualty hazards; UL develops standards for motors for hazardous locations through cooperation with manufactures;  UL has standards and tests for explosion proof and dust ignition proof motors which must be met and passed before application of the UL label







Variable Torque:
  loads which may require reduced torque when driven at speeds less than the base speed of the load, but requiring increased torque when driven at speeds greater than the base speed of the load; variable torque loads usually decrease with the square of the speed



 



Vertical Motor: A motor being mounting vertically (shaft up or down) as in many pumps applications







“Y” Frame:   NEMA designation identifying an AC induction motor frame with special mounting dimensions







“Z” Frame:   NEMA designation identifying an AC induction motor frame where all mounting dimensions are standard with the exception of the shaft