Should you use BS EN 61439 or BS EN 60204 for machine control panels?

BS EN 61439, relates to low-voltage switchgear and controlgear assemblies. BS EN 60204 is a multi-part machinery safety standard relating to the electrical equipment of machines. Both are the British Standard equivalents of IEC international standards.

BS EN 61439 is a seven-part standard. Part 1 provides general rules and is used in conjunction with one of the other six parts, each of which covers a different field of application. As an aside, compliance with Part 1 alone cannot be claimed; compliance must be with Part 1 and one of the other Parts.

Part 2 applies to power switchgear and controlgear assemblies.

Part 3 is for distribution boards intended to be operated by ordinary persons (DBO).

Assemblies for Construction Sites (ACS) is Part 4.

Part 5 is for assemblies for power distribution in public electricity networks.

Busbar trunking systems (busways) are covered by Part 6.

Part 7 covers assemblies in specific applications such as marinas, camping sites, market squares and electric vehicle charging stations.

In addition, Part 0 is a Published Document (Technical Report) PD IEC/TR 61439-0 that provides guidance to specifying assemblies.

For machine control panels, compliance is common with Parts 1 and 2. However, this is discussed later in this article.

BS EN 60204 is also a multi-part standard. Part 1 presents general requirements. The other parts are as follows:

- Part 11 covers equipment for voltages above 1000 V AC or 1500 V DC and not exceeding 36 kV.

- Part 31 is for safety and EMC requirements for sewing machines, units and systems.

- Part 32 is the requirements for hoisting machines.

- Part 33 is for semiconductor fabrication equipment.

In addition, there is a Technical Specification, IEC TS 60204-34:2016, covering requirements for machine tools (there is no separate British Standard equivalent for this). This may be upgraded from a Technical Specification to a full Part of the standard in the future.

Geographical regions

The standards - or parts thereof - with which a machine control panel should comply depends on the machine and its application. If the machine is destined for the GB market, it should be UKCA marked according to the Supply of Machinery (Safety) Regulations. On the other hand, if it is heading for the European Union or other states where the European Machinery Directive has been implemented (including Northern Ireland, under the Northern Ireland Protocol), it needs to be CE marked. To confuse matters further, the UK Government has decided to accept CE Marking for the foreseeable future.

In most cases, in the UK, a machine needs need to comply with the Supply of Machinery (Safety) Regulations or the Machinery Directive - which are, for the time being, all but identical. Specific components within the machine or its control panel may need to comply with other regulations and directives, such as those for low voltage or electromagnetic compatibility. Furthermore, if a panel builder is undertaking the design and the manufacture, it is probable the panel will require UKCA/CE marking according to the low voltage and/or EMC regulations/directives.

Designated/harmonised standards

The simplest way to demonstrate compliance with the relevant essential requirements of the regulations and directives is to comply with the applicable designated/harmonised standards for the British/European markets. These standards provide a 'presumption of conformity'.

Earlier, we mentioned the 61439 and 60204 series of standards. The BS EN 61439 series is not designated/harmonised to the GB Supply of Machinery (Safety) Regulations or the European Machinery Directive. No part provides a presumption of conformity with the essential requirements.

However, BS EN 60204 Parts 1, 11, 31, 32 and 33 are designated/harmonised and should be complied with as appropriate when a machine is UKCA/CE marked to the Supply of Machinery (Safety) Regulations or Machinery Directive. A machine can only be CE marked as a whole, including the control panel, so the control panel should be designed, manufactured and installed according to the relevant parts of BS EN 60204.

Note that it is not mandatory to comply with designated/harmonised standards, but doing so is likely to be the most expedient way of meeting the essential requirements of the regulations/directives.

61439 versus 60204

Depending on the machine, the components it incorporates and the operating conditions, it may need to comply with some aspects of the 61439 series of standards. In some cases, therefore, it may be appropriate to design, manufacture and install a machine control panel in compliance with specific clauses or subclauses of the relevant Parts of BS EN 61439.

But (and it is a very big 'but') complying with 61439 does not mean 60204 can be ignored. Panel builders, system integrators and machine builders often seem to be familiar with the 61439 series and therefore apply it, but they are oblivious to the existence of the 60204 series. This situation is potentially dangerous because the 60204 series of machinery safety standards have been drafted to reduce the risk of injury to machine users and maintainers. If BS EN 60204-1 and other relevant Parts are not complied with, there could be risks such as electric shock and overheating of cabling and components, resulting in a fire that puts lives at risk. Even if non-compliance does not cause injury, it can still give rise to unreliability, premature failures and unplanned downtime that can be very costly for the end-user. The supplier's profitability suffers when the machine is still under warranty.

Those panel builders and others familiar with the 60204 series do not find compliance expensive or time-consuming. Compliance can save time and cost; for example, correct labelling of terminals and wiring can speed commissioning and fault-finding.

Benefits of compliance

Complying with the standard during the design, manufacture and installation costs far less than undertaking rework. In addition, a machine that is fully compliant with BS EN 60204-1 is less likely to give rise to problems when a customer conducts a pre-delivery UKCA/CE marking audit. Moreover, last-minute rectification can also jeopardise delivery dates.

Typically, machine control panels should comply with BS EN 60204-1 and maybe one of the other Parts if appropriate. In addition, some clauses and subclauses of BS EN 61439-1 and BS EN 61439-2, may also need consideration. It is vital that the documentation presents the rationale behind which aspects of BS EN 61439 have been applied and which have not, and a formal risk assessment plays a significant role in informing this rationale.

Exporting to the EU

Panel builders that design and manufacture panels for the EU market - or other regions where the European Low Voltage Directive and EMC Directive have been implemented - are likely to need to CE mark the panels. In addition, the panel builder needs to have an economic operator based in the EU so they can comply with EU Regulation 2019/1020 on market surveillance. In most cases, the best option is to appoint an EU Authorised Representative (EUAR).

Similarly, if machine builders are exporting to the EU, the machinery needs to be CE marked in accordance with the EU Machinery Directive. Not only do GB machine builders need to follow the CE marking process, but they must also name somebody on the Declaration of Conformity (DoC) who is authorised to compile the technical file. This person must be established in the EU, which can be problematic for many GB-based machine builders.

Fortunately, Safe Machine has a sister company based in the Republic of Ireland, Hold Tech Files. This company can act as an EUAR and can be named on a machine's DoC. This is all managed via a simple web-based portal where clients can sign a mandate, pay a fee and upload the relevant files to a secure server.

Note that the Machinery Directive is being superseded by the new Machinery Regulation in 2027. One of the many changes is that the Machinery Regulation is more specific about the requirements in relation to economic operators.

- To support companies working with BS EN 60204-1, Paul Skyrme and Derek Coulson jointly authored a white paper, 'BS EN 60204-1 for machine builders and panel builders - a guide to avoiding common errors'. This document presents approximately 80 ways in which this standard's requirements are often not met. Safe Machine has published the white paper to help machine builders, system integrators and panel builders improve their compliance. You can download a free copy here.