Last edit: 27/09/2025
THE DOUBT
Manufacturers of machines and industrial control panels often face uncertainty about which electrical standard should be applied for the design and CE marking of industrial control panels.
Different schools of thought exist on this matter:
- Some maintain that IEC 60204-1 — Safety of machinery – Electrical equipment of machines – Part 1: General requirements is the sole applicable standard when designing the electrical equipment of machinery.
- Others contend that IEC 61439-2 — Low-voltage switchgear and controlgear assemblies – Part 2: Power switchgear and controlgear assemblies must be applied in full and can even be regarded as the only relevant standard for the electrical cabinets of machinery.
CONSIDERATIONS
This doubt is understandable, as neither of the two standards can be strictly classified as the product standard for industrial control panels.
IEC 61439-2 is the reference standard for low-voltage switchgear and controlgear assemblies, while IEC 60204-1 sets out requirements and recommendations for the electrical equipment of machines in order to ensure:
-
the safety of persons and property;
-
the consistency of control response;
-
the ease of maintenance.
IEC 60204-1 is the technical standard for the entire electrical installation of a machine, not specifically for its control panels; however, it provides all the requirements needed to design a safe industrial control panel. It is broadly equivalent to NFPA 79 in the United States and C22.2 No. 301 in Canada.
By contrast, IEC 61439-2 is the product standard for switchgear and controlgear assemblies, meaning low-voltage distribution panels.
In other words, the reality is that there is no dedicated technical standard for Industrial Control Panels (ICPs) used in machinery.
Yes — that is the truth!
But this absence does not justify choosing IEC 61439-1 as the technical standard for ICPs. Unfortunately, this misconception persists in some quarters.
In the USA the situation is clear: the product standard for switchgears is UL 891, the one for industrial control panel is UL 508A. While the one for the Electrical Installation of Machinery is NFPA 79.
But let’s look at the language used in the two standards.
In the current edition of IEC 61439-2 (2012) we find the following language:
This part of the IEC 61439 defines the specific requirements of power switchgear and controlgear assemblies as follows:
– Assemblies for which the rated voltage does not exceed 1000 V in case of a.c. or 1500 V in case of d.c.;
– Stationary or movable assemblies with or without enclosure;
– Assemblies intended for use in connection with the generation, transmission, distribution and conversion of electrical energy and for the control of electric energy consuming equipment;
– Assemblies designed for use under special service conditions, for example in ships and in rail vehicles provided that the other relevant specific requirements are complied with;
– Assemblies designed for electrical equipment of machines. Supplementary requirements for assemblies forming part of a machine are covered by the IEC 60204 series.
It is clear that the scope of the standard extends to Industrial Control Panels (ICPs) and that IEC 60204-1 provides supplementary requirements for their design and safety.
However, in the latest edition of IEC 61439-2 (published in May 2020), the final paragraph was deleted specifically to clarify that IEC 60204-1 is the primary reference standard for control panels.
Manufacturers may, where appropriate, still apply certain provisions of IEC 61439-2 as supplementary requirements.
A comparable revision was introduced in the latest edition of IEC 61439-1 (published in July 2020).
Consequently, IEC 61439-1 and IEC 61439-2 are no longer intended to be directly applicable to Industrial Control Panels.
Once these new editions are harmonised under the Low Voltage Directive (LVD), it will be the responsibility of the panel manufacturer — within the framework of the risk assessment required for CE marking — to determine which specific provisions of EN 61439-1/2 to adopt voluntarily as supplementary measures.
That is in line with what is stated in the 2018 edition of EN 60204-1 (or 2016 edition of IEC 60204-1):
In addition to the requirements of IEC 60204-1, depending upon the machine, its intended use and its electrical equipment, the designer may select parts of the electrical equipment of the machine that are in compliance with relevant parts of the IEC 61439 series.
This means, for example, that for an industrial control panel equipped with a 25 A main switch, the manufacturer could reasonably apply the requirements of IEC 60204-1 alone.
Conversely, for a machinery control panel with a 1 000 A main switch, the designer should apply IEC 60204-1 and, in addition, follow the relevant provisions of IEC 61439-2 applicable to such high-current assemblies.
CONCLUSION
Ultimately, the machinery manufacturer — or the manufacturer of the industrial control panel — shall comply with the requirements of IEC 60204-1.
In addition, the manufacturer shall determine, through the risk assessment required for CE marking, whether to apply specific provisions of IEC 61439-2 that are relevant to the safe design and construction of the control panel.
For example, when building an in-house busbar trunking system, the manufacturer can refer to the ampacity calculation rules given in IEC 61439-1.