Detail of GB/T 755-2019

Introduction of GB/T 755-2019

This standard is developed in accordance with the rules given in GB/T 1.1-2009. This standard replaces GB/T 755-2008 Rotating electrical machines - Rating and performance. In addition to a number of editorial changes, the following technical changes have been made with respect to GB/T 755-2008: ——the thermal equilibrium condition is modified as: the temperature rises of the heating parts of the machine do not vary by more than a gradient of 1K per half hour (see 3.25, 3.25 in 2008 version); ——the term "runaway speed" is added (see 3.33); ——the requirements on water coolant temperature are added (see 6.5, 6.5 of 2008 edition); ——the stipulation that the variable frequency motor shall meet the requirements of IVIC is added, and the bus transfer and fast reclosing requirements are added (see 7.1); ——Table 3 “CCC symbol designation” is added (see Table 3 of 7.2.4); ——Item 5 of Table 4 in 7.3 is modified: synchronous generator driven by steam turbines or combustion gas turbines with rated output ≥10 MVA (see Table 4, Table 3 in 2008 edition); ——provisions on the impulse voltage insulation class, in the case of machines designed to operate without partial discharges are added (see 7.5); ——a new insulation class 200(N) is added and some temperature rise limits in Table 8 are modified (see Table 8, Table 7 in 2008 edition); ——the calculation formula of Item 1b in Table 10 is modified (see Table 10, Table 9 in 2008 edition); ——marking of IC codes, IVIC for variable frequency motors, IE codes for energy efficiency grade is added (see 10.2); ——Items 1 and 2 for tolerances are added (see 12.2; 12.2 in 2008 edition); ——EMC requirements for excitation synchronous machines without brushes are added (see 13.1). This standard, by means of translation, is identical to IEC 60034-1:2017 Rotating electrical machines – Part 1: Rating and performance The Chinese documents consistent and corresponding with the normative international documents in this standard are as follows: ——GB/T 156-2017 Standard voltages (IEC 60038: 2009, MOD); ——GB/T 1971-2006 Rotating electrical machines - Terminal markings and direction of rotation (IEC 60034-8:2002, IDT); ——GB/T 1993-1993 Cooling methods for rotating electrical machines (eqv IEC 60034-6: 1991); ——GB/T 4026-2010 Basic and safety rules for logo identification of man-machine interface equipment terminals and conductor terminals (IEC 60445:2006, IDT); ——GB 4343.1-2018 Electromagnetic compatibility requirements for household appliances, electric tools and similar apparatus-Part 1: Emission (CISPR 14-1: 2011, IDT); ——GB 4706.1-2005 Household and similar electrical appliances-Safety-Part 1: General requirements (IEC 60335-1:2004, IDT); ——GB/T 4772.1-1999 Dimensions and output series for rotating electrical machines -Part 1: Frame numbers 56 to 400 and flange numbers 55 to 1080 (IEC 60072-1:1991, IDT); ——GB/T 4772.2-1999 Dimensions and output series for rotating electrical machines -Part 2: Frame numbers 355 to 1000 and flange numbers 1 180 to 2360 (IEC 60072-2: 1990, IDT); ——GB/T 4772.3-1999 Dimensions and output series for rotating electrical machines-Part 3: Small built-in motors- Flange numbers BF10 to BF50 (IEC 60072-3: 1994, IDT); ——GB 4824-2013 Industrial, scientific and medical (ISM) radio-frequency equipment-Disturbance characteristics-Limits and methods of measurement (IEC/CISPR 11: 2010, IDT); ——GB/T 4942.1-2006 Degrees of protection provided by the integral design of rotating electrical machines (IP code) - Classification (IEC 60034-5: 2000, IDT); ——GB 5226.1-2008 Electrical safety of machinery - Electrical equipment of machines - Part 1: General requirements (IEC 60204-1: 2005, IDT); ——GB/T 6113.101-2016 Specification for radio disturbance and immunity measuring apparatus and methods - Part 1-1: Radio disturbance and immunity measuring apparatus - Measuring apparatus (CISPR 16-1-1: 2010, IDT); ——GB/T 11021-2014 Electrical insulation-Thermal evaluation and designation (IEC 60085:2007, IDT); ——GB/T 17948 (All Parts) Rotating electrical machines - Functional evaluation of insulation systems [IEC 60034-18 (All Parts)]; ——GB/T 22715-2016 Impulse voltage withstand levels of form-wound stator coils for rotating a.c. machines (IEC 60034-15:2009, IDT); ——GB/T 25442-2018 Standard methods for determining losses and efficiency of rotation electrical machines from tests (excluding machines for traction vehicles) (IEC 60034-2-1: 2014, IDT); ——GB/T 32877-2016 Specific test method for determining loss and efficiency of inverter-fed AC induction motors (IEC/TS 60034-2-3:2013, IDT). The following editorial changes have been made in this standard: ——the standard name is changed to Rotating electrical machines - Rating and performance; ——the clerical errors in the original document are corrected. This standard was proposed by China Electrical Equipment Industrial Association. This standard is under the jurisdiction of the National Technical Committee on Electric Rotating Machinery of Standardization Administration of China (SAC/TC 26). The previous editions of standard replaced by this standard are as follows: ——GB 755-1987, GB 755-2000, GB/T 755-2008. Rotating electrical machines - Rating and performance 1 Scope This standard is applicable to all rotating electrical machines except those covered by other IEC standards, for example, IEC 60349. Machines within the scope of this standard may also be subject to superseding, modifying or additional requirements in other standards, for example, IEC 60079 and IEC 60092. Note: If particular clauses of this document are modified to meet special applications, for example machines subject to radioactivity or machines for aerospace, all other clauses apply insofar as they are compatible. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. GB/T 2900.25-2008 Electrotechnical terminology - Rotating electrical machines (IEC 60050-411: 1996, IDT) GB/T 21210-2016 Starting performance of single-speed three-phase cage induction motors (IEC 60034-12: 2016, IDT) IEC 60027-1 Letter symbols to be used in electrical technology—Part 1: General IEC 60027-4 Letter symbols to be used in electrical technology—Part 4: Rotating electric machines) IEC 60034-2 (all parts) Rotating electrical machines—Part 2: Standard methods for determining losses and efficiency from tests (excluding machines for traction vehicles)] IEC 60034-3 Rotating electrical machines—Part 3: Specific requirements for synchronous generators driven by steam turbines or combustion gas turbines IEC 60034-5 Rotating electrical machines—Part 5: Degrees of protection provided by the integral design of rotating electrical machines (IP code)—Classification IEC 60034-6 Rotating electrical machines—Part 6: Methods of cooling(IC code)] IEC 60034-8 Rotating electrical machines—Part 8: Terminal markings and direction of Rotation) IEC 60034-15 Rotating electrical machines—Part 15: Impulse voltage withstand levels of form-wound stator coils for rotating a.c. machines) IEC 60034-18 (all parts) Rotating electrical machines—Part 18: Functional evaluation of insulation systems IEC 60034-18-41 Rotating electrical machines—Part 18-41: Partial discharge free electrical insulation systems (Type I) used in rotating electrical machines fed from voltage converters—Qualification and quality control tests IEC TS 60034-25 Rotating electrical machines—Part 25: AC electrical machines used in power drive systems—Application guide IEC 60034-29 Rotating electrical machines—Part 29: Equivalent loading and superposition techniques—Indirect testing to determine temperature rise IEC 60034-30 (all parts) Rotating electrical machines—Part 30: Efficiency classes of A.C. motors(IE-code) IEC 60038 IEC standard voltages IEC 60060-1 High-voltage test techniques—Part 1: General definitions and test requirements) IEC 60072 (all parts) Dimensions and output series for rotating electrical machines IEC 60085 Electrical insulation—Thermal evaluation and designation IEC 60204-1 Safety of machinery—Electrical equipment of machines—Part 1: General requirements) IEC 60204-11 Safety of machinery—Electrical equipment of machines—Part 11: Requirements for HV equipment for voltages above 1 000 V a.c. or 1 500 V d.c. and not exceeding 36 kV) IEC 60335-1: 2010 Household and similar electrical appliances—Safety—Part 1: General requirements) IEC 60445 Basic and safety principles for man-machine interface, marking and identification—Identification of equipment terminals, conductor terminations and conductors) IEC 60664-1 Insulation coordination for equipment within low-voltage systems—Part 1: Principles, requirements and tests) IEC 61148 Terminal markings for valve de-vice stacks and assemblies and for power conversion equipment) IEC 61293 Marking of electrical equipment with ratings related to electrical supply—Safety Requirements) CISPR 11 Industrial, scientific and medical equipment—Radiofrequency disturbance characteristics—Limits and methods of measurement) CISPR 14 (all parts) Electromagnetic compatibility—Requirements for household appliances, electric tools and similar apparatus CISPR 16 (all parts) Specification for radio disturbance and immunity measuring apparatus and methods 3 Terms and definitions For the purposes of this document, the terms and definitions given in GB/T 2900.25- 2008 and the following apply. Note 1: For definitions concerning cooling and coolants, other than those in 3.17 to 3.22, see IEC 60034-6. Note 2: For the purposes of this document, the term ‘agreement’ means ‘agreement between the manufacturer and purchaser’. 3.1 rated value quantity value assigned, generally by a manufacturer, for a specified operating condition of a machine Note: The rated voltage or voltage range is the rated voltage or voltage range between lines at the terminals. [GB/T 2900.25-2008, definition 411-51-23] 3.2 rating set of rated values and operating conditions [GB/T 2900.25-2008, definition 411-51-24] 3.3 rated output value of the output included in the rating 3.4 load all the values of the, in case of a generator, electrical and, in case of a motor, mechanical quantities that signify the demand made on a rotating machine by an electrical circuit or a mechanism at a given instant Note: GB/T 2900.25-2008, modified, definition 411-51-01. 3.5 no-load (operation) state of a machine rotating with zero output power (but under otherwise normal operating conditions) Note: GB/T 2900.25-2008, modified, definition 411-51-02. 3.6 full load load which causes a machine to operate at its rating [GB/T 2900.25-2008, definition 411-51-10] 3.7 full load value quantity value for a machine operating at full load Note: This concept applies to power, torque, current, speed, etc. [GB/T 2900.25-2008, definition 411-51-11] 3.8 de-energized and rest complete absence of all movement and of all electrical supply or mechanical drive [GB/T 2900.25-2008, definition 411-51-03] 3.9 duty statement of the load(s) to which the machine is subjected, including, if applicable, starting, electric braking, no-load and rest and de-energized periods, and including their durations and sequence in time [GB/T 2900.25-2008, definition 411-51-06] 3.10 duty type continuous, short-time or periodic duty, comprising one or more loads remaining constant for the duration specified, or a non-periodic duty in which generally load and speed vary within the permissible operating range [GB/T 2900.25-2008, definition 411-51-13] 3.11 cyclic duration factor ratio between the period of loading, including starting and electric braking, and the duration of the duty cycle, expressed as a percentage [GB/T 2900.25-2008, definition 411-51-09] 3.12 locked rotor torque greatest steady-state r.m.s. current taken from the line with the motor held at rest, over all angular positions of its rotor, at rated voltage and frequency [GB/T 2900.25-2008, Definition 411-48-06] 3.13 locked rotor current greatest steady-state r.m.s. current taken from the line with the motor held at rest, over all angular positions of its rotor, at rated voltage and frequency [GB/T 2900.25-2008, Definition 411-48-16] 3.14 pull-up torque(of an a.c. motor) smallest steady-state asynchronous torque which the motor develops between zero speed and the speed which corresponds to the breakdown torque, when the motor is supplied at the rated voltage and frequency Note 1: this definition does not apply to those asynchronous motors of which the torque continually decreases with increase in speed. Note 2: in addition to the steady-state asynchronous torques, harmonic synchronous torques, which are a function of rotor load angle, will be present at specific speeds. At such speeds, the accelerating torque may be negative for some rotor load angles. Experience and calculation show this to be an unstable operating condition and therefore harmonic synchronous torques do not prevent motor acceleration and are excluded from this definition. 3.15 breakdown torque(of an a.c. motor) maximum steady-state asynchronous torque which the motor develops without an abrupt drop in speed, when the motor is supplied at the rated voltage and frequency Note: this definition does not apply to motors with torques that continually decrease with increase in speed. 3.16 pull-out torque(of a synchronous motor) maximum torque which the synchronous motor develops at synchronous speed with rated voltage, frequency and field current 3.17 cooling procedure by means of which heat resulting from losses occurring in a machine is given up to a primary coolant, which may be continuously replaced or may itself be cooled by a secondary coolant in a heat exchanger [GB/T 2900.25-2008, definition 411-44-01] 3.18 coolant medium, liquid or gas, by means of which heat is transferred [GB/T 2900.25-2008, definition 411-44-02] 3.19 primary coolant medium, liquid or gas, which, being at a lower temperature than a part of a machine and in contact with it, removes heat from that part [GB/T 2900.25-2008, definition 411-44-03] 3.20 secondary coolant medium, liquid or gas, which, being at a lower temperature than the primary coolant, removes the heat given up by this primary coolant by means of a heat exchanger or through the external surface of the machine [GB/T 2900.25-2008, definition 411-44-04] 3.21 direct cooled (inner cooled) winding winding mainly cooled by coolant flowing in direct contact with the cooled part through hollow conductors, tubes, ducts or channels which, regardless of their orientation, form an integral part of the winding inside the main insulation Note: in all cases when ‘indirect’ or ‘direct’ is not stated, an indirect cooled winding is implied. [GB/T 2900.25-2008, definition 411-44-08] 3.22 indirect cooled winding any winding other than a direct cooled winding Note: in all cases when ‘indirect’ or ‘direct’ is not stated, an indirect cooled winding is implied. [GB/T 2900.25-2008, definition 411-44-09] 3.23 supplementary insulation independent insulation applied in addition to the main insulation in order to ensure protection against electric shock in the event of failure of the main insulation 3.24 moment of inertia sum (integral) of the products of the mass elements of a body and the squares of their distances (radii) from a given axis 3.25 thermal equilibrium state reached when the temperature rises of the heating parts of the machine do not vary by more than a gradient of 1K per half hour Note 1: thermal equilibrium may be determined from the time-temperature rise plot when the straight lines between points at the beginning and end of two successive intervals of half hour each have a gradient of 1K or less per half hour or 2K or less per hour. Note 2: GB/T 2900.25-2008, modified, definition 411-51-08. 3.26 thermal equivalent time constant time constant, replacing several individual time constants, which determines approximately the temperature course in a winding after a step-wise current change 3.27 encapsulated winding winding which is completely enclosed or sealed by moulded insulation [GB/T 2900.25-2008, definition 411-39-06] 3.28 rated form factor of direct current supplied to a d.c. motor armature from a static power converter ratio of the r.m.s. maximum permissible value of the current Irms,max N to its average value IavN (mean value integrated over one period) at rated conditions: (1) 3.29 current ripple factor ratio of the difference between the maximum value Imax and the minimum value Imin of an undulating current to two times the average value Iav (mean value integrated over one period): (2) Note 1: for small values of current ripple, the ripple factor may be approximated by the following expression: (3) Note 2: the above expression may be used as an approximation if the resulting calculated value of qi is equal to or less than 0.4. 3.30 tolerance permitted deviation between the declared value of a quantity and the measured value 3.31 type test test of one or more machines made to a certain design to show that the design meets certain specifications Note: the type test may also be considered valid if it is made on a machine which has minor deviations of rating or other characteristics. These deviations should be subject to agreement. [GB/T 2900.25-2008, Definition 411-53-01]

Contents of GB/T 755-2019

Foreword I 1 Scope 2 Normative references 3 Terms and definitions 4 Duty 5 Rating 6 Site conditions 7 Electrical operating conditions 8 Thermal performance and tests 9 Other performance and tests 10 Rating plates 11 Miscellaneous requirements 12 Tolerances 13 Electromagnetic compatibility (EMC) 14 Safety Annex A (Informative) Guidance for the application of duty type S10 and for establishing the value of relative thermal life expectancy TL Annex B (Informative) Electromagnetic compatibility (EMC) limits Bibliography