How does Lux Intelligent monitor emergency light performance?

Lux Intelligent’s unique addressable module (PLU) design monitors the actual light output of a luminaire via a fibre optic that typically points at luminaires light source.

This light level is measured against a calibrated value established at the time of manufacture of the PLU. 

If for some reason, a light level cannot be simply monitored in this fashion, it is possible to use another means of monitoring with an alternative interface component such as a current monitor.  Again, this is uniquely calibrated to ensure that the value measured confirms if the light source is working correctly.