ESE Devices

All information that follows is intended to elucidate the protection approach of ESE devices and is not provided for the purposes of design or advice. The theory underpinning the performance of ESE devices is based upon the electric characteristics of lightning formation. Lightning initiates with a downward leader, propagating to any direction. Once it approximates to the objects placed on the ground, any of them can be struck. The objective of an external lighting protection system is to control the lightning striking point thus providing the lightning current a path to the ground without damaging the structure. The main feature of ESE devices is the emission of the continuous upward leader before any other object within is protected area. The standards define this characteristic using a parameter called advance time(t). The advance time determines the protection radius of each air terminal. If the triggering occurs earlier, then the distance where the downward leader is intercepted increases, thus avoiding the lightning strike in a wider area.

  • The protection radius of an ESE device is related to its height relative to the area intended to be protected.
  • The ESE air terminal must be installed at least 2m higher than any other element within its protected area.
  • Any installation of an ESE device must be undertaken with great care as ESE devices need to be able to maintain performance in all types of weather conditions; any damage leading to rain ingress could short-circuit the ESE device and render it ineffective.
  • Each ESE device must be connected to the earthing using an external down conductor. Two or more down conductors are needed for structures over 28m in height, and when the horizontal part of the down conductor is larger than the vertical part.
  • Each down conductor must have a low inductance earth termination system, which is oriented away from the structure and has a lower resistance than 10Ω.
  • 3 fixing clips should be installed for every metre of down conductor.
  • Down conductors must not come within 3m of external gas pipes.
  • Down conductors should have a cross-section of at least 50mm². Since lightning current is impulsional then flat conductors (tape) are preferable than round conductors because they have a larger surface for the same amount of material.
  • The Dat Controler®Plus ESE devices have gained AENOR product quality seal of certification.

Find out more about these sustem design considerations in our FM Sudafix Catalogue