Standard

BS EN IEC 60034-30-3:2024

Rotating electrical machines - Efficiency classes of high voltage AC motors (IE-code)

Current

•

Published:

31 Mar 2024

1 Scope

This part of IEC 60034 specifies efficiency classes for fixed-speed three-phase high-voltage cage induction motors in accordance with IEC 60034‑1 that

• have a rated voltage exceeding 1 000 V, but not exceeding 11 kV;
• have a rated power from 200 kW to 2 000 kW;

NOTE 1 Motors with rated power above 2 000 kW are produced in such small numbers and are designed and produced with a focus on achieving an optimum efficiency anyway, even though fulfilling increasingly special requirements that assigning efficiency classes would be an additional effort without the result of any countable energy saving.
• have two, four or six poles;
• are rated for single-speed line-operation;
• are intended for direct-on-line starting at rated or at reduced voltage and rated frequency;
• are constructed to any degree of protection;
• are designed for cooling methods IC411, IC511, IC611, IC01 or IC81W;
• are capable of continuous operation at their rated operating point (torque/power, speed) with a temperature rise within the specified insulation temperature class;

NOTE 2 Most motors covered by this document are rated for duty type S1 (continuous duty). However, some motors that are rated for other duty cycles are still capable of continuous operation at their rated power and these motors are also covered.
• are rated for any ambient temperature or coolant temperature within the range of − 20 °C to + 60 °C;

NOTE 3 Motors rated for temperatures outside the range − 20 °C and + 60 °C are considered to be of special construction and are consequently excluded from this document.
• are rated for an operating altitude up to 2 000 m above sea level;

NOTE 4 The rated efficiency and the efficiency class are based on a rating for altitudes up to 1 000 m above sea level.
• have a locked-rotor current I_l at stand-still and supply with rated voltage and frequency before application of any IEC or agreed tolerance in the range I_l / I_N ≥ 4,5;
• are designed for a customer load torque during starting not exceeding an envelope with a minimum of 25 % of the rated torque at low speed and a square shape T ~ n² up to a maximum load torque at full speed of 60 % of the rated torque in case of 2 pole motors or 100 % of the rated torque in case of 4 pole or 6 pole motors, respectively, (see Figure 1), After starting is completed, the load torque of 2 pole motors is increased to 100 % of the rated torque;
• have to accelerate an external moment of inertia as defined by the customer requirements not exceeding the values given in Table 1 considering all start up conditions defined in this document for not more than three consecutive starts from cold condition or two starts from hot condition, respectively;
• are designed for a minimum locked-rotor steady state supply voltage of at least 80 % of the rated voltage during starting.

Figure 1 — Envelope of the load torque during starting: Load torque during starting in % of rated torque over speed in % of rated speed

Table 1 — Maximum external moment of inertia

Number of poles	2		4		6
Frequency Hz	50	60	50	60	50	60
Rated output kW	Moment of inertia J kg m²
200	25	15	115	75	310	200
220	25	15	120	80	330	210
250	25	15	130	85	360	230
280	30	20	140	90	400	250
315	30	20	150	100	440	270
355	35	20	170	110	480	300
400	35	25	190	120	530	330
450	40	25	210	130	580	360
500	45	30	230	140	640	400
560	50	30	250	150	700	440
630	55	35	280	170	780	490
710	60	35	310	190	870	550
800	65	40	340	210	970	610
900	70	45	380	230	1 100	680
1 000	80	50	420	260	1 200	750
1 120	90	55	460	290	1 300	830
1 250	100	60	510	320	1 450	920
1 400	110	65	570	360	1 650	1 000
1 600	120	70	640	400	1 850	1 150
1 800	130	80	720	440	2 050	1 300
2 000	150	90	800	490	2 300	1 450

NOTE 1 The values of the moment of inertia given are in terms of mr² where m is the mass and r is the mean radius of gyration.

NOTE 2 Moment of inertia is defined in ISO 3: 1973, 3.7.

NOTE 3 If necessary, linear interpolation is permitted between two adjacent values.

Excluded are:

• Motors with mechanical commutators or slip-rings;
• Motors with 8 or more poles;
• Multi-speed motors;
• Motors with customer starting torque requirements exceeding the load torque envelope above, and motors exceeding the maximum external inertia defined in Table 1;
• Motors designed specifically for operation fed by a power electronic frequency converter with a temperature rise within the specified insulation thermal class or thermal class;
• Motors completely integrated with the driven machine (for example pumps, fans and compressors). This means that the motor cannot be designed in such a way as to enable the motor to be separated from the driven unit, i.e. it is not possible to operate the separated motor without the driven unit;
• Submersible motors specifically designed to operate wholly immersed in a liquid;
• Smoke extraction motors;
• Motors dedicated to operate in explosive atmospheres;
• Motors for operation in nuclear plants, especially nuclear power plants.

Product Details

Descriptors

Electric machines

AC motors

Efficiency

High-voltage equipment

Alternating-current motors

ICS Codes

29.160.01 Rotating machinery in general

29.160.10 Components for rotating machines

29.160.30 Motors

Committee

PEL/2

International relationships

Identical to:

IEC 60034-30-3 Ed.1.0

EN 60034-30-3 Ed.1.0

ISBN

978 0 539 13989 1

Publisher

BSI