IEC/SC 22G - IEC_SC_22G

specifies electromagnetic compatibility (EMC) requirements for power drive systems (PDSs). A PDS is defined in 3.1. These are adjustable speed a.c. or d.c. motor drives. Requirements are stated for PDSs with converter input and/or output voltages (line-to-line voltage), up to 35 kV a.c. r.m.s.

IEC 61800-9-1:2017 specifies the general methodology to energy efficiency standardization for any extended product by using the guidance of the extended product approach (EPA). This document specifies the methodology of determination of losses of the extended product and its sub-parts. It is applicable to motor systems operated by a motor starter or by a converter (power drive systems).

IEC 61800-9-2:2017 specifies energy efficiency indicators of power electronics (complete drive modules, CDM), power drive systems (PDS) and motor starters, all used for motor driven equipment. It specifies the methodology for the determination of losses of the complete drive module (CDM), the power drive system (PDS) and the motor system. It defines IE and IES-classes, their limit values and provides test procedures for the classification of the overall losses of the motor system. Furthermore, this document proposes a methodology for the implementation of the best energy efficiency solution of drive systems. This depends on the architecture of the motor driven system, on the speed/load profile and on the operating points over time of the driven equipment.

2017-05-02: D156/C084 - Ratified standards not being made available.
Published following BT156/DG10475/DV

IEC 61800-5-2:2016 is available as IEC 61800-5-2:2016 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition. IEC 61800-5-2:2016 specifies requirements and makes recommendations for the design and development, integration and validation of safety related power drive systems (PDS(SR)) in terms of their functional safety considerations. It applies to adjustable speed electrical power drive systems covered by the other parts of the IEC 61800 series of standards as referred in IEC 61800-2. IEC 61800-5-2, which is a product standard, sets out safety-related considerations of PDS(SR)s in terms of the framework of IEC 61508, and introduces requirements for PDS(SR)s as subsystems of a safety-related system. It is intended to facilitate the realisation of the electrical/ electronic/programmable electronic (E/E/PE) parts of a PDS(SR) in relation to the safety performance of safety sub-function(s) of a PDS. This edition includes the following significant technical changes with respect to the previous edition: a) rational added in the scope why low demand mode is not covered by this standard, b) definition added for: "category" and "safety function", c) "Other sub-functions" sorted into "Monitoring sub-functions" and "Output functions", d) deleted "proof test" throughout the document because for PDS(SR) a proof test is not applicable, e) replaced the term "safety function" by "safety sub-function" throughout the document, f) Updated references to IEC 61508 series Ed.2010, g) Added the principle rules of ISO 13849-1 and reference to tables of ISO 13849-2, h) 6.1.6 Text replaced by Table 2, i) 6.1.7 Integrated circuits with on-chip redundancy matched to changed requirement in IEC 61508-2: 2010, Annex E, j) 6.2.8 Design requirements for thermal immunity of a PDS(SR) k) 6.2.9 Design requirements for mechanical immunity of a PDS(SR), l) 6.1.6 SIL for multiple safety sub-functions within one PDS(SR), m) 6.1.7 Integrated circuits with on-chip redundancy, n) 6.2.1 Basic and well-tried safety principles, o) 6.2.2.1.4 Diagnostic test interval when the hardware fault tolerance is greater than zero, p) 6.2.5.2.7 PDS(SR) parameterization, q) 9 Test requirements, r) 9.3 Electromagnetic (EM) immunity testing, s) 9.4 Thermal immunity testing, t) 9.5 Mechanical immunity testing, u) Annex A Sequential task table, v) Annex D, D.3.16, Motion and position feedback sensors updated, w) Annex E Electromagnetic immunity (EM) requirement for PDS(SR), x) Annex F Estimation of PFDavg value for low demand with given PFH value.

IEC 61800-7-201:2015 is available as IEC 61800-7-201:2015 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition. IEC 61800-7-201:2015 specifies profile type 1 for power drive systems (PDS). Profile type 1 can be mapped onto different network technologies. This edition includes the following significant technical changes with respect to the previous edition: - Updates, clarifications and enhancements.

IEC 61800-7-203:2015 specifies profile type 3 for power drive systems (PDS). Profile type 3 can be mapped onto different communication network technologies. This edition includes the following significant technical changes with respect to the previous edition: a) minor updates in the Base Mode Parameter Access mechanism; b) minor updates and simplification in the Application Class 3 state machine definition.

IEC 61800-7-301:2015 is available as IEC 61800-7-301:2015 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition. IEC 61800-7-301:2015 specifies the mapping of the profile type 1 (CiA 402) specified in IEC 61800-7-201 onto different network technologies. This edition includes the following significant technical changes with respect to the previous edition: - Additional mappings to communication systems are included (Mapping to CC-Link IE Field Network and Mapping to EPA).

IEC 61800-7-302:2015 specifies the mapping of the profile type 2 (CIP MotionTM) specified in IEC 61800-7-202 onto different network technologies. This edition includes the following significant technical changes with respect to the previous edition: - update of patent information; - updates to the Connection Format and connection points; - support of an additional object.

IEC 61800-7-204:2015 specifies profile type 4 for power drive systems (PDS). Profile type 4 can be mapped onto different communication network technologies. This edition includes the following significant technical change with respect to the previous edition: - update of drive parameters and their specification.

IEC 61800-7-304:2015 specifies the mapping of the profile type 4 (SERCOS) specified in IEC 61800-7-204 onto different network technologies. This edition includes the following significant technical change with respect to the previous edition: Update of mapping specification.

IEC 61800-7-303:2015 specifies the mapping of the profile type 3 (PROFIdrive) specified in IEC 61800-7-203 onto different network technologies. This edition includes the following significant technical changes with respect to the previous edition: - Enhanced definition of the using of PROFINET IO Diagnosis ASE and Alarm ASE; - Minor updates in the mapping of the Base Mode Parameter Access to PROFIBUS and PROFINET.

IEC 61800-7-202:2015 specifies profile type 2 (CIP MotionTM) for Power Drive Systems (PDS). Profile type 2 can be mapped onto different communication network technologies. This edition includes the following significant technical changes with respect to the previous edition: a) update of patent information; b) new revision of the Drive Profile and Drive Axis specifications, with multiple clarifications and enhancements.

IEC 61800-7-1:2015 specifies a generic interface between power drive system(s) (PDS) and the application control program in a controller. The generic PDS interface is not specific to any particular communication network technology. Annexes of this part of IEC 61800 specify the mapping of the different drive profiles types onto the generic PDS interface. The functions specified in this part of IEC 61800 are not intended to ensure functional safety. This requires additional measures according to the relevant standards, agreements and laws. This edition includes the following significant technical changes with respect to the previous edition: a) mapping of drive profile type 1 onto additional network technologies; b) minor updates in the subclauses for profile types 1, 2 and 4, in relation with corresponding changes in the dedicated IEC 61800-7-20x parts.

IEC 61800-2:2015 applies to adjustable speed electric a.c. power drive systems, which include semiconductor power conversion and the means for their control, protection, monitoring, measurement and the a.c. motors. It applies to adjustable speed electric power drive systems intended to feed a.c. motors from a BDM connected to line-to-line voltages up to and including 1 kV a.c. 50 Hz or 60 Hz and/or voltages up to and including 1,5 kV d.c. input side. NOTE 1 Adjustable speed electric a.c. power drive systems intended to feed a.c. motors, and with rated converter input voltages above 1 000 V a.c. are covered by IEC 61800-4. NOTE 2 Adjustable speed electric d.c. power drive systems intended to feed d.c. motors are covered by IEC 61800-1. NOTE 3 For adjustable speed electric a.c. power drive systems having series-connected electronic power converter sections, the line-to-line voltage is the sum of the series connected input voltages. Traction applications and electric vehicles are excluded from the scope of this standard. IEC 61800-2:2015 is intended to define the following aspects of an a.c. power drive system (PDS): - principal parts of the PDS; - ratings and performance; - specifications for the environment in which the PDS is intended to be installed and operated; - other specifications which might be applicable when specifying a complete PDS. This standard provides minimum requirements, which may be used for the development of a specification between customer and manufacturer. This edition includes the following significant technical changes with respect to the previous edition. a) Clause 1 (Scope) has been updated, b) Clause 2 (Normative references) has been updated, c) Clause 3 (Definitions) has been updated including fundamental definitions to be used across the IEC 61800 series of standards, d) Clause 4 has been updated with respect to: 1) description of the basic topology for BDM/CDM/PDS (4.2); 2) ratings and performance (4.3 and 4.4); 3) reference to applicable standards within the IEC 61800 series with respect to EMC (IEC 61800-3), Electrical safety (IEC 61800-5-1), Functional safety (IEC 61800-5-2), Load duty aspects (IEC TR 61800-6), Communication profiles (IEC 61800-7 series) and Power interface voltage (IEC TS 61800-8) to avoid conflicting requirements (4.5, 4.6, 4.7, 4.10, 4.11, 4.12); 4) update of requirement for ECO design (4.8); 5) update of requirement for environmental evaluation (4.9); 6) implementation of requirement for explosive atmosphere (4.13). e) Clause 5 has been updated with test requirement in order to provide a clear link between design requirement and test requirement. f) Clause 6 has been updated to harmonize the marking and documentation requirement within the IEC 61800 series. g) Existing Annexes A to G have been deleted and replaced with new Annexes A to C.

This part of EN 50598 specifies the process and requirements to implement environmentally conscious product design principles, to evaluate ecodesign performance and to communicate potential environmental impacts for power electronics (e.g. complete drive modules, CDM), power drive systems and motor starters, all used for motor driven equipment in the power range of 0,12 kW up to 1 000 kW and low voltage (up to 1 000 V) applications over the whole life cycle. It defines the content for 2 different environmental declarations based on EN ISO 14021: - The basic version - which, in this context, will be referred to as an environmental declaration type II, with basic data and qualitative statements on ecodesign. - The full version - which, in this context, will be referred to as an environmental declaration type II+, based upon a life cycle assessment and including quantitatively evaluated potential environmental impacts. For that the general principles of EN ISO 14025 are taken into account and product category rules [PCR] for motor system components are included to ensure a harmonized approach. This part of EN 50598 is harmonized with the applicable generic and horizontal environmental standards and contains the additional details relevant in this context for the above mentioned products.

2011-11-24: Publication editing allocated to cpalagi@cencenelec.eu

IEC/TR 61491:2010 presents an overview and guidance for IEC 61158, IEC 61784-1, IEC 61784-2 and IEC 61800-7 with respect to a real-time serial interface between the control unit and its associated devices, which is utilized to transmit periodic and non periodic data. This interface is intended to apply to industrial machines, such as machine tools, with multiple devices connected via this interface. This interface supports different operation modes. This first edition of the technical report cancels and replaces the second edition of IEC 61491, published in 2002. The changes are primarily to make reference to material that was moved to IEC 61158, IEC 61784 and IEC 61800-7 series of standards.

It specifies requirements for adjustable speed power drive systems, or their elements, with respect to electrical, thermal and energy safety considerations. It does not cover the driven equipment except for interface requirements. It applies to adjustable speed electric drive systems which include the power conversion, drive control, and motor or motors. Excluded are traction and electric vehicle drives. It applies to d.c. drive systems connected to line voltages up to 1 kV a.c., 50 Hz or 60 Hz and a.c. drive systems with converter input voltages up to 35 kV, 50 Hz or 60 Hz and output voltages up to 35 kV. The major areas of change in this edition are the following: addition of alphabetical Table 1 in Clause 3; addition of Table 2 in 4.1 for relevance to PDS/CDM/BDM; addition of Table 4 summary of decisive voltage class requirements; expansion of subclause on protective bonding (4.3.5.3); clarification of distinction between touch current and protective conductor current; revision of section on insulation (now 4.3.6) to include solid insulation; addition of overvoltage categories I and II to HV insulation voltage; revision of section on Solid insulation (now 4.3.6.8); addition of high-frequency insulation requirements (4.3.6.9, Annex E); addition of requirements for liquid-cooled PDS (4.4.5); addition of climatic and vibration tests (5.2.6); clarification of voltage test procedure to avoid over-stress of basic insulation (5.2.3.2.3); revision of short-circuit test requirement for large, high-voltage and one-off PDS (now 5.2.3.6); addition of informative Annex B for overvoltage category reduction

IEC 61800-2:2015 applies to adjustable speed electric a.c. power drive systems, which include semiconductor power conversion and the means for their control, protection, monitoring, measurement and the a.c. motors. It applies to adjustable speed electric power drive systems intended to feed a.c. motors from a BDM connected to line-to-line voltages up to and including 1 kV a.c. 50 Hz or 60 Hz and/or voltages up to and including 1,5 kV d.c. input side. NOTE 1 Adjustable speed electric a.c. power drive systems intended to feed a.c. motors, and with rated converter input voltages above 1 000 V a.c. are covered by IEC 61800-4. NOTE 2 Adjustable speed electric d.c. power drive systems intended to feed d.c. motors are covered by IEC 61800-1. NOTE 3 For adjustable speed electric a.c. power drive systems having series-connected electronic power converter sections, the line-to-line voltage is the sum of the series connected input voltages. Traction applications and electric vehicles are excluded from the scope of this standard. IEC 61800-2:2015 is intended to define the following aspects of an a.c. power drive system (PDS): - principal parts of the PDS; - ratings and performance; - specifications for the environment in which the PDS is intended to be installed and operated; - other specifications which might be applicable when specifying a complete PDS. This standard provides minimum requirements, which may be used for the development of a specification between customer and manufacturer. This edition includes the following significant technical changes with respect to the previous edition. a) Clause 1 (Scope) has been updated, b) Clause 2 (Normative references) has been updated, c) Clause 3 (Definitions) has been updated including fundamental definitions to be used across the IEC 61800 series of standards, d) Clause 4 has been updated with respect to: 1) description of the basic topology for BDM/CDM/PDS (4.2); 2) ratings and performance (4.3 and 4.4); 3) reference to applicable standards within the IEC 61800 series with respect to EMC (IEC 61800-3), Electrical safety (IEC 61800-5-1), Functional safety (IEC 61800-5-2), Load duty aspects (IEC TR 61800-6), Communication profiles (IEC 61800-7 series) and Power interface voltage (IEC TS 61800-8) to avoid conflicting requirements (4.5, 4.6, 4.7, 4.10, 4.11, 4.12); 4) update of requirement for ECO design (4.8); 5) update of requirement for environmental evaluation (4.9); 6) implementation of requirement for explosive atmosphere (4.13). e) Clause 5 has been updated with test requirement in order to provide a clear link between design requirement and test requirement. f) Clause 6 has been updated to harmonize the marking and documentation requirement within the IEC 61800 series. g) Existing Annexes A to G have been deleted and replaced with new Annexes A to C.

This part of IEC 61800 applies to adjustable speed electric DC power drive systems, which include semiconductor power conversion and the means for their control, protection, monitoring, measurement and the DC motors. It applies to adjustable speed electric power drive systems intended to feed DC motors from a BDM/CDM connected to line-to-line voltages up to and including 1 kV AC 50 Hz or 60 Hz and/or voltages up to and including 1,5 kV DC input side. NOTE 1 Adjustable speed electric AC power drive systems intended to feed AC motors are covered by IEC 61800-2. NOTE 2 This document can be used as a reference for adjustable speed electric power drive systems, intended to feed DC motors from a BDM/CDM connected to line-to-line voltages up to and including 1,5 kV AC, 50 Hz or 60 Hz and/or voltages up to and including 2,25 kV DC input side. Traction applications and electric vehicles are excluded from the scope of this document. This document is intended to define the following aspects of a DC power drive system (PDS): - principal parts of the PDS; - ratings and performance; - specifications for the environment in which the PDS is intended to be installed and operated; - other specifications which might be applicable when specifying a complete PDS. This document provides minimum requirements, which may be used for the development of a specification between customer and manufacturer. Compliance with this document is possible only when each topic of this document is individually specified by the customer developing specifications or by product standard committees developing product standards. For some aspects which are covered by specific PDS product standards in the IEC 61800 series, this document provides a short introduction and reference to detailed requirements in these product standards.

Provides alternative methods for specifying ratings for adjustable speed electrical power drive systems (PDS) and in particular their basic drive modules (BDM

specifies electromagnetic compatibility (EMC) requirements for power drive systems (PDSs). A PDS is defined in 3.1. These are adjustable speed a.c. or d.c. motor drives. Requirements are stated for PDSs with converter input and/or output voltages (line-to-line voltage), up to 35 kV a.c. r.m.s.

Applies to adjustable speed a.c. drive systems that include power conversion, control equipment and a motor. Excluded are traction for railway applications and electrical vehicle drives. Applies to power drive systems with converter voltages (line-to-line voltage), between 1 kV a.c. and 35 kV a.c., input side 50 Hz or 60 Hz, and load side frequencies up to 600 Hz. Requirements for voltages above 15 kV are not included and are defined by agreement between the manufacturer and the system supplier. For power drive systems, with voltages above 1 kV, using a step-down input transformer and/or a step-up output transformer in connection with a low voltage converter (below 1 000 V), EN 61800-2 applies. Gives the characteristics of the converters, their topologies and their relationship with the complete a.c. drive system. It also states their performance requirements with respect to ratings, normal operating conditions, overload conditions, surge withstand capabilities, stability, protection, a.c. line earthing, topologies and testing. Furthermore, it deals with application guidelines, such as control strategies, torsion analysis, recommendations for earthing and drive system component integration.

Applies to general purpose adjustable speed d.c. driven systems which include the power conversion, control equipment, and also a motor or motors. Excluded are traction and electrical vehicle drives. Applies to power driven systems (PDS) connected to line voltages up to 1 kV a.c., 50 Hz or 60 Hz.

IEC 61800-5-3:2021, which is a product standard, specifies requirements and makes recommendations for the design and development, integration and validation of safety-related encoder (Encoder(SR)) in terms of their functional safety considerations, electrical safety and environmental conditions. It applies to Encoder(SR), being sensors as part of a PDS(SR). This document can also be referred to and used for Encoder(SR) in any other safety-related application, for example safety-related position monitoring. This document is applicable where functional safety of an encoder is claimed and the Encoder(SR) is operating mainly in the high demand or continuous mode. The requirements of IEC 61800-5-2:2016 for PDS(SR) apply to Encoder(SR) as applicable. This document includes additional or different requirements for Encoder(SR). It sets out safety-related considerations of Encoder(SR) in terms of the framework of IEC 61508 (all parts), and introduces requirements for Encoder(SR) as subsystems of a safety-related system. It is intended to facilitate the realisation of the electrical/electronic/programmable electronic (E/E/PE) and mechanical parts of an Encoder(SR) in relation to the safety performance of safety sub-function(s) of an Encoder(SR).

This European Standard provides a general methodology to energy efficiency standardization for any extended product including a motor system by using the methodological guidance of the extended product approach (EPA). It enables product committees for driven equipment with included motor systems to interact with the relative power losses of the included motor system (e.g. PDS) in order to determine the system energy efficiency aspects for the extended product by calculation. This should be based on specified calculation models for speed/load profiles, the load-time profiles and relative power losses of appropriate torque versus speed operating points. This part of the EN 50598 series specifies the methodology of determination of losses of the extended product including a motor system and its sub-parts. This framework is explained by an example for pumps. This part of the standard does not specify requirements for environmental impact declarations.

This European Standard specifies the energy efficiency indicators for power electronics (e.g. complete drive modules, CDM), power drive systems and motor starters, all used for motor driven equipment in the power range of 0,12 kW up to 1 000 kW. It specifies the methodology for determination of losses of the complete drive module (CDM), the power drive system (PDS) and the complete motor system. It defines IE and IES-classes, their limit values and provides test procedures for the classification of the overall losses of the motor system. Furthermore, this part of EN 50598 proposes a methodology for characterization of the best energy efficiency solution to be implemented. This depends on the motor driven system architecture, the speed/load profile and the operating points over time of the driven equipment. The methodology of the extended product approach and the semianalytical models are defined in Part 1 of the series. The structure of this EN 50598 contains the following: - the losses of a standardized reference PDS (RPDS) and the mathematical model for their calculation are given and classified; - the reference load/motor (RM) and the reference CDM (RCDM) are defined and can be used to determine the efficiency class of a motor system when one of its constituents is unknown; - the requirements for determining the losses of a real PDS are given and are classified in comparison to the RPDS; - the requirements for the type testing and the content of user documentation; - some illustrations of losses in an overall system as an example are given in annexes; - information about system and drive topologies are given in annexes. Specific data for power losses of RCDM, RM, RPDS and IE/IES-classes are given for low voltages (100 V up and equal to 1 000 V), single axis AC/AC power drive systems with three phase induction motors. Geared motors need to be treated as standard motors. All provided reference data is derived from PDS with induction motors, but valid for all types of PDS with other types of motors. High voltage equipment does not need to be assessed in this edition of the document. In prEN 50598-3, the methodology for eco-design for environmental impact is defined. NOTE The 50598 series does not cover energy efficiency classification of driven equipment, but provides input for the assessment of extended product approach.

It specifies a generic interface between power drive system(s) (PDS) and the application control program in a controller. The generic PDS interface is not specific to any particular communication network technology. Annexes of this part specify the mapping of the different drive profiles types onto the generic PDS interface.

It specifies profiles for Power Drive Systems (PDS) and their mapping to existing communication systems by use of a generic interface model. It also specifies the mapping of the profile type 2 (CIP MotionTM) specified in IEC 61800-7-202 onto different network technologies. DeviceNet (CP 2/3), ControlNet (CP 2/1), EtherNet/IP (CP 2/2).

It specifies profiles for Power Drive Systems (PDS) and their mapping to existing communication systems by use of a generic interface model and also profile type 4 for Power Drive Systems (PDS). Profile type 4 can be mapped onto different communication network technologies.

It specifies profiles for Power Drive Systems (PDS) and their mapping to existing communication systems by use of a generic interface model as well as profile type 1 for Power Drive Systems (PDS). Profile type 1 can be mapped onto different communication network technologies.

It specifies profiles for Power Drive Systems (PDS) and their mapping to existing communication systems by use of a generic interface model as well as profile type 2 (CIP Motion ) for Power Drive Systems (PDS). Profile type 2 can be mapped onto different communication network technologies.

It specifies profiles for Power Drive Systems (PDS) and their mapping to existing communication systems by use of a generic interface model. It also specifies how the profile type 3 (PROFIdrive) specified in IEC 61800-7-203 onto different network technologies. PROFIBUS DP, see Clause 4 and PROFINET IO, see Clause 5.

It specifies profiles for Power Drive Systems (PDS) and their mapping to existing communication systems by use of a generic interface model. It also specifies the mapping of the profile type 1 (CiA 402) specified in IEC 61800-7-201 onto different network technologies: CANopen, EtherCAT, ETHERNET Powerlink.

It specifies profiles for Power Drive Systems (PDS) and their mapping to existing communication systems by use of a generic interface model It also specifies the mapping of the profile type 4 (SERCOS) specified in IEC 61800-7-204 onto different network technologies: SERCOS I / II, SERCOS III, EtherCAT.

It specifies profiles for Power Drive Systems (PDS) and their mapping to existing communication systems by use of a generic interface model as well as profile type 3 for Power Drive Systems (PDS). Profile type 3 can be mapped onto different communication network technologies.

It specifies requirements and makes recommendations for the design and development, integration and validation of PDS(SR)s in terms of their functional safety considerations. It applies to adjustable speed electric drive systems covered by the other parts of the IEC 61800 series of standards.

specifies requirements for adjustable speed power drive systems, or their elements, with respect to electrical, thermal and energy safety considerations. It does not cover the driven equipment except for interface requirements. It applies to adjustable speed electric drive systems which include the power conversion, drive control, and motor or motors. It applies to d.c. drive systems connected to line voltages up to 1 kV a.c., 50 Hz or 60 Hz and a.c. drive systems with converter input or output voltages up to 35 kV, 50 Hz or 60 Hz.

Corrigendum to EN issued May 2001 * Superseded by EN 61800-3:2004

Defines a real-time optical serial interface between the control unit and its associate drives which is utilized to transmit periodic and non periodic data.

Applies to general purpose adjustable speed a.c. drive systems which include power conversion, control equipment, and also an a.c. motor or motors. Excluded are tractional and electrical vehicle drives. Applies to systems connected to line voltages up to 1 kV a.c., 50 Hz or 60 Hz, and load side frequency up to 600 Hz.

Specifies EMC requirements for adjustable speed a.c. or d.c. motor drives connected to mains supplies up to 1000v a.c.. Defines limits and test methods

Provides alternative methods for specifying ratings for semiconductor power convertors for adjustable speed electric drive systems, particularly for d.c. motor drives. It has been established with respect to, but is not restricted to, convertors of line or machine-commutated type. It is not intended to cover adjustable speed drives for traction purposes.