Specific applications

Some current sources have special  lighting as main user :

• greenhouses with energy-efficient lamps and other single phased lighting
• tertiary territory and warehouses : high amount of fluorescent lamps

In these networks the neutral can warm up quite well through which the isolation can melt or even can get fire.

Current in the neutral can have two causes :

• an unstable load of the phase
• a third harmonic current in the phases that is accumulated in the neutral

The installer will pull over the phases steady. If there is a steady load of the phases and there is despite it a significant current in the neutral, than is this a sign of the presence of third harmonics.

This problem can be faced with a filter especially for the third harmonic.

You can find more information in rubric tertiary .