How can I select an MCB or RCD for various types of lighting loads?

Answer:

The Lighting Industry Federation states in their Technical Statement No.21: High Frequency Luminaires.

MCB protection
At switch on, HF ballasts draw a surge of current from the supply. MCBs having a Type C trip characteristic in accordance with EN 60898 are recommended as a minimum. The Electrical Contractor or the ballast manufacturer may specify a higher classification.The number of HF ballasts which may be operated in a circuit may vary with the ballast design and therefore the consultant/installer is advised to refer to the manufacturers information for guidance.

RCD on each circuit
The RFI filters incorporated in HF ballasts include capacitors connected between line and earth and neutral and earth. This arrangement will allow a small amount of 50Hz current to flow through the earth conductor which is interpreted as an earth leakage current by a Residual Current Device. If RCD protection is required account must be taken of the sum of the leakage currents when using a common RCD. The use of a time delayed RCD or individual RCD for each lighting circuit is recommended.