acoustic enclosures connecing to lightning protection.

Acoustic enclosures for heat pumps, air conditioning, and refrigeration systems can be ideally integrated into a variety of environments thanks to the free choice of exterior color, usually powder coating.

But be careful: in many cases, acoustic enclosures must also be connected to lightning protection.

What is often overlooked is that the powder coating has an electrically insulating effect and a very high surface resistance (greater than 1 TΩ), which is why it does not allow electrical contact for lightning protection systems. This greatly reduces the conductivity of the coated surface, and direct discharge of lightning currents via the powder-coated surfaces is not guaranteed without additional measures.

To make powder coatings conductive, special so-called dissipative powder coatings (ESD coatings) are used. These contain conductive additives. These reduce electrostatic charge and enable a certain degree of electrical conductivity, which, however, is usually not sufficiently dimensioned or specified for lightning protection systems.

For lightning protection applications, this means:

1)
Conventional powder coatings prevent a secure electrical connection due to their insulation.

2)
Contact points in lightning protection must be mechanically removed from the powder coating to establish metallic, conductive contact.

3)
​Dissipative powder coatings are a special type, but are rarely used in lightning protection because they cannot safely conduct the high current loads of a lightning strike.