Electricity + Control June 2015

Bernd Leibig studied Electrical Engineering at the

University of applied Science Georg-Simon-Ohm

Nuremberg. Between 1993 and 2008 he held various

positions in R&D, sales and project management at

DIEHL Stiftung Nuremberg / Germany. Since 2008 he

has been product manager, surge protection red / line

at DEHN + SÖHNE GmbH + Co. Kg. in Neumarkt / Germany.

Dietmar Dürr studied Electrical Engineering at Grundig

Academy in Nuernberg. In1998 he joined Dornier

Medical Systems as a field Service Engineer. From

2000 to 2009 he was employed by DEHN + SÖHNE, in

various positions. He worked as key account manager

for SMA from 2009 to 2014. He is currently area sales

manager with DEHN + SÖHNE.

Enquiries: Alexis Barwise. Email

ELECTRICAL PROTECTION + SAFETY

Figure 7: Test set-up for a complete LED street lighting system in

the laboratory.

Conclusion

The laboratory tests in cooperation with LED light manufacturers

and the practice-oriented system test of a complete LED system,

consisting of a cable distribution cabinet, metal mast, cable junc-

tion box and LED light – in conjunction with practical experiences

are important elements of an efficient protection concept for LED

street lighting systems. A well-founded protection concept can

only be implemented by means of a complete system consisting

of cascaded SPDs (see

Figure 5

) which is specifically developed for

this application, in the cable junction box or in the LED light and

a coherent earthing concept where all metal masts must be con-

nected to the protective conductor of the SPDs used. This allows

safety control potential differences and ensures the availability

of the LED street lighting system – also in the case of surges.

This is the only way to ensure that an investment for retrofitting

street lighting systems with the new LED technology achieves the

predicted lifetime and uncalculated follow-up costs are prevented.

References

[1] IEC 61000-4-5. 2014. Surge immunity.

[2] EN 61643-11. 2011. Low voltage surge protective devices. Part

11: Surge Protective Devices connected to low voltage power

systems – requirements and test methods.

[3] IEC 60364-4-41:2005. Low-voltage electrical installations - Part

4-41: Protection for safety - Protection against electric shock.

[4] IEC EN 60598-1. 2008. Practical guide to testing and certifica-

tion requirements for luminaires.