Mode Lighting and the 17th edition

The recent introduction of the 17th edition regulations means a number of changes in the protection of circuits.

Mode Lighting units such as the tiger and Evolution have no main isolator and hence even in the previous edition of the regulations a mechanical isolator was required to isolate the incoming power to the unit to carry out mechanical and electronic maintenance.

The best solution seems to be three independent RCBo’s mounted in an external housing local to the Evolution control pack.
1 RCBO for each phase/bank of breakers – this requires that the pack neutrals are split for each RCBO and that the pack power supply (3 phase + neutral connection) is rewired to the mains supply side of the RCBOs. A warning label should be applied to the pack to this effect.
If a single phase supply is used for Evo/Tiger, it becomes easier, in that assuming RCBOs are only needed for one or two of the banks of breakers, the PSU can be powered from the remaining bank (ie all 3 PSU live inputs can be connected to the bottom of one set of breakers).
In all cases, it is essential that the load live and neutral outputs are connected to the relevant set of outputs, otherwise the resultant imbalance will cause tripping.
If you need advice on design or installation of a lighting control system please contact us and we can look over your project and ensure it meets all the current standards.