What is the BS EN 61439 low voltage switchgear and control gear assemblies standard?

IEC 61439 is the International Electrotechnical Commission standard which covers low voltage switchgear and controlgear assemblies. The standard gives details on the requirements of these products through testing and other verification methods.

It is a replacement for IEC 60439 and is now the industry standard requirement for ALL low voltage switchgear and controlgear Panel Assemblies
IEC 61439 has been achieved by less than 1% of the Control Panel manufacturers in the UK.

This standard is a significant change from the previous one, one of the most surprising changes for some will be the removal of the terms ‘type tested assembly’ and ‘partially type tested assembly’, these have been replaced by ‘design verification’.

Design Verification

The twelve design verification characteristics are split down into two main areas, that of ‘construction’ and ‘performance’.

Construction

Strength of materials and parts
This looks at the suitability of plastics and metals to prove the long term capabilities of the equipment.

Degree of protection of enclosures
This references the same standard as before.

Incorporation of switching devices and components
This requires the panel builder to ensure that devices are installed in line with manufacturer’s instructions.

Terminals for external conductors
This, again, puts the onus on the panel builder to ensure that the contractor will be able to terminate his cables on to the switchboard.

Performance

Temperature Rise
One of the biggest areas of change in the standard revolves around this area. No longer can you fit a device into a compartment and rate it at a level it would not be capable of carrying without exceeding the limits set by the standard. The standard now requires that the maximum current a circuit is capable of carrying, within the temperature limitations, is noted as its rating, irrespective of what the device manufacturers claims for the device alone.

Short circuit withstand strength
This is principally the same set of tests as per the previous version of the standard, with a few amendments.

Mechanical operation
This ensures the components of the system are mounted in such a way that through normal use, they will not fail or change the capabilities of the switchboard. In this case the test value is set at 200 operations.

JME Responsibilities

Upon completion of the above, and moving into production, the standard requires routine verification be carried out by the Control Panel Manufacturer to ensure continued compliance to the design verified solution is met. These routine verifications must be carried out on each and every MCC / Control Panel / Switchboard that is manufactured and is principally a simplified subset of the 12 design verification characteristics, but this cannot be seen just as a job for the final QC department, since important areas such a device ratings, terminal sizes, swapping of components etc. needs to be fully investigated prior to any work being started.
To ensure JME are fully certified to manufacture electrical control panels to the new 61439:2009 standard, they are assessed by the ECA annually to receive a technical compliance certificate, an achievement less than 1% of UK Panels Builders have achieved