API TR 11L6 pdf download Technical Report on Electric Motor Prime Mover for Beam Pumping Unit Service
4.1.3 Size Rating
Motors covered by this technical report shall be rated in horsepower(HP) or kilowatt (kw) on a contiruous-duty basis.4.1.4Synchronous Speed Rating
The synchronous speed rating at 60 Hz is 1200 RPM or as specified on the attached Motor Data Sheet (seeAnnex A). This technical report also permits the motor synchronous speed of 900 RPM or 1000 RPM.
4.1.5voltage, Frequency and Phase Ratings
Voltage ratings shall be 460/796 or 460 Volts AC,60 Hertz,3 Phase or 380V,50 Hertz, 3 Phase. The 50 Hzsynchronous speed is 1000 RPM.
4.1.6 Motor Enclosures
Motor enclosures shall be open drip proof (ODP) or totally enclosed fan cooled (TEFC) suitable for unclassified areas.s a minimum,enclosures shall meet ODP-guarded specifications in accordance with NEMA MG 1or TEFCspecification in accordance with NEMA MG 1.
4.1.7 NEMA Motor Designs and Starting Characteristics
Motors shall be NEMA Design D as specified by NEMA MG 1 with a slip of 5 % to 8 % or ultra-high slip design.Motorsshall be capable of accelerating load under conditions as specified in NEMA MG 1.
4.1.8 Frame Assignments
Motors furmished in accordance with this technical report, shall as a minimum comply with the frame size assignmentsas per NEMA MG 13-1984 for T-frame motors or according to NEMA MG 13-1956 for U-frame motors.
4.1.9 Motor Frame Material
For cast iron or other materials used, the motor manufacturer shall identify the material used for motor frames, andshields, and other structural parts; corrosion resistant treatment; test for corrosion resistance.
4.1.10Insulation System (Service Factor, and Temperature Rise)
The thermal rating of the insulation system shall be a minimum of Class F as defined in NEMA MG 1.When operatedat rated voltage, frequency and load, the temperature rise shall not exceed 80 C by resistance for Class F insulation,90 ‘C by resistance for Class F encapsulated, or 125 “C by resistance for Class H insulation in accordance withIEEE 112. Standard motors shall have a 1.15 Service Factor. ultra-high slip motors shall have a 1.0 Service Factorwithout exceeding the allowable temperature rise of the insulation system as determined in accordance withIEEE 112.
The power terminal box shall be located on the right side of the enclosure facing the shaft end of the motor inaccordance with NEMA Type F-2 construction.
The preferred number of motor leads should be six. As an option for voltage and torque variation, the user mayspecify 3, 9, or 12 leads.
4.1.13 Bearing Life
Bearings shall be selected to provide L-10 rating life of 26,280 hours minimum (3 years continuous) per ABMA-9 orABMA-11 as applicable.Calculations shall be based on extermal loads calculated for NEMA bolted application limits inaccordance with NEMA MG 1 and internal loads defined by the manufacturer.Regressable bearings shall beprovided on frame sizes above 286T.
4.2Other Electrical Design Considerations4.2.1 Power Supply Variations
126.96.36.199 Motors shall operate on a continuous basis at rated load with variation in the voltage or the frequency notexceeding the following conditions:
a)± 10 % of rated voltage, with rated frequency;b)土 5 % of rated frequency, with rated voltage; and
c) combination of voltage and frequency variation of 10 % (sum of absolute values) of the rated values, provided that
the frequency variation does not exceed ± 5 % of rated frequency.
188.8.131.52 Motors shall operate on a continuous basis at rated load and frequency when the voltage unbalance at themotor terminals is less than or equal to 1 % as calculated according to NEMA MG 1.
184.108.40.206 When elevation or ambient temperatures other than specified in 4.1.2 are noted on the data sheet, the motorshall be derated in accordance with NEMA MG 1.
4.2.2 All motors shall have nonhygroscopic insulation systems including loads and connections. Internal windingencapsulation may be specified.Coil ends shall be braced to prevent insulation cracking and fatigue from movementdue to starting, operating under cyclic load conditions, and vibrations inherent to a beam pumping system.
4.2.3The motor insulation system shall be protected against the severe conditions listed in 4.1.2.As minimum theinsulation system must pass the salt spray test as specified in ASTM B117.
4.2.4 The motor leads in the motor terminal box shall be constructed of copper motor lead wire and be permanentlyidentified.
4.3Other Mechanical Design Considerations4.3.1 Bearings and Lubrication
220.127.116.11 Regressable type bearings should be regressable without any disassembly, and shall contain a reservoirequipped with an outlet for elimination of purged grease. Inlet and outlet openings shall have removable plugs.
18.104.22.168 Regressable bearings should be supplied with as grease compatible with operating conditions specfied in4.1.2.The manufacturers preferred type of grease shall be stated in the maintenance and operating instructionsprovided with the motor.