Answer

Regularly testing your Residual Current Device (RCD) is vital for electrical safety. An RCD monitors electrical currents and swiftly disconnects power if it detects an imbalance, preventing potential electric shocks. 

To carry out a self-test on an RCD, press the test button firmly and quickly every six months; the device should trip, cutting off the electricity supply. If it doesn't, consult a qualified electrician for further inspection. Regular testing confirms the RCD's ability to protect against earth faults and electrical shocks, maintaining the safety of your electrical installation.

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