In the world of surge protection we differentiate between impacts of high energy currents with an energy content up to 10 MJ/Ohm caused by a direct lightning strike and low energy transients just caused by electrical and magnetic effects, known as the indirect effects of lightning, similar to an antenna of a radio.

By international consensus such a direct lightning current could be described / simulated with a so called 10/350 µs current pulse compared to a 8/20 µs current pulse, just to simulate the indirect effects of lightning. The major difference of these pulses is the duration of the current flow, which for the 10/350 µs pulse is approximately 15 times longer than the low energy pulse.

Consequently, it is obvious that a surge arrester, with the purpose to protect against direct impacts, should be tested against the 10/350 µs pulse and not only with the low energy 8/20 µs pulse, which is most common in North America. The consequence of this mismatch could be in the best case the loss of the surge protector and the protected equipment and in the worst case the destruction of the whole installation, which most likely will happen by using the above mentioned cord line protector only.

DEHN, in the market since 1910, is offering a wide range of lightning current and surge protection products for power applications as well as for any kind of instrumentation and control circuits. DEHN's product portfolio includes devices rated for these high energy 10/350 µs current pulses, and for the low energy impact of inducted voltages simulated by the 8/20 µs pulse. Furthermore, the DEHN Red/Line product family are all energy-coordinated with each other.

An example of such a "lightning current" arrester is our DEHNbloc Maxi. This device is based on a triggered crow bar, but designed to avoid the former disadvantage of a high let through voltage and short circuit current issue. For more information, please contact us info@r3alimited.com.