Success Stories
Palermo-Messina motorway (Italy)

Luminous flux regulators for tunnel reinforcements


The design choices, made already in the nineties, took into account the requirements of the CIE 88, regarding the need to provide for a modulation of the luminous flux in particular in the reinforcement area, at the entrance to the tunnel, but also in the pre- exit.

The designer has identified three main levels of lighting - full sun, medium sun, no sun - according to the reading made by the luminance sensor placed outside the entrance, at a distance equal to the stop distance for the maximum allowed speed. in that stretch. However, three levels do not fully satisfy the requirements of CIE 88 as the jump between one level and another is too high and can cause over-lighting situations in different operating conditions, as well as high energy consumption.


This is why the choice to include luminous flux regulators in the reinforcement and pre-exit circuits, capable of reducing the flux emitted by SAP lamps by up to 50%.

It is therefore possible to recover half of the increase / reduction in flow that occurs by switching a step on or off and therefore ultimately determining conditions of better comfort for the human eye. Given that a large part of the lighting power installed in the tunnel is necessary for the operation of the reinforcement circuits, it is also clear that the luminous flux regulator also determines substantial energy savings.

Revetec supplied the vast majority of the regulators installed in the Palermo - Messina tunnels. These have been supplied in the G version, for interiors, with IP21 protection degree, to be controlled from the general electrical panel. The end customer particularly appreciated the static system used for regulation, which is maintenance-free and has no moving parts, which is essential in such hostile environments.