The ALPS ESE 60 µs has been added to our line up of ESE lightning protection systems with with laboratory testing confirming the efficiency. We now provide ESE lightning protection systems with a ∆T (triggering advance) of 35.5 µs and 60 µs. This lightning protection device is the largest in our line-up, as stated in NFC 17-102: 2011 "The maximum value for ΔT, whatever are the test results, is 60 μs."
Testing the efficiency
The efficiency of an ESE device is carried out in a high voltage laboratory and has to meet the requirements stated in NFC 17-102: 2011.
"Average values TESEAT and TSRAT and standard deviations σESEAT and σSRAT are calculated. The tested lighting conductor is an ESEAT if both the following conditions are met: • TESEAT < TSRAT • ΣESEAT < 0,8 σSRAT • TPTS - TPDA > 10 μs"
"The maximum value for ΔT, whatever are the test results, is 60 μs."
Testing confirms the ALPS ESE 60 μs is an ESEAT device with an advanced triggering time of 62.7 μs, with 60 μs being the maximum no matter the test results.
Radius Of Protection
The radius of protection Rp of an ESE is given by the European standard NFC 17-102 (September 2011).
It depends on the ESEAT efficiency ∆T of the ALPS ESE measured in a high voltage laboratory, on the levels of protection I, II, III or IV calculated according to the lightning risk assessment guides or standards (NF C 17-102 annex A or IEC 62305-2, guides UTE C 17-100-2 or UTE C 17-108) and on the height h of the lightning air terminal over the area to be protected (minimum height = 2 m).
The protection radius is calculated according to Annex C in European standard NF C 17-102. For ALPS ESE, the value of ∆T used in the protection radius calculations is 60 µs (∆T = T’SRAT – T’ESEAT = 358.9 – 296.2 = 62.7 µs) "The maximum value for ΔT, whatever are the test results, is 60 μs."
Therefore our new ALPS ESE 60 μs provides the largest Rp (radius of protection) possible according to standard for ESE systems NFC 17-102: 2011. This can be seen below.