Electrical power imbalance in a building can cause personal injury, loss of property or death. Property occupants need a high level of personal protection against electrical faults. Residual Current Devices monitor electricity flowing through the mains to a house, business or office to prevent the occupants of that building from dangerous situations whenever there is an imbalance on a circuit. RCDs are highly sensitive and cut off electricity within milliseconds of detecting an electrical imbalance. Each domestic building should be installed with a minimum of two Residual Circuit Device safety switches for even division of electrical circuits and maximum safety in case of an electricity surge, commercial properties should consider RCD protecting each circuit individually so as to minimise disruption in the event of a particular circuit failing.


Functional testing of RCDs

According to the UK’s department of housing website https://www.hse.gov.uk, you should undertake functional testing of your RCD quarterly. The RCD has a button that is used to check whether the switch is functioning correctly. Upon pressing this button, the power should go off if the RCD is functioning well. However, if the power fails to go off, you should call in an electrician to re-test it. The electrician will determine whether the switch is faulty or you just tested it wrongly. He will then repair or replace it if it is faulty.


How is an RCD tested?

Under standard wiring requirements published on https://www.beama.org.uk/when testing an RCD, it should cut off electricity in 40 milliseconds when you pass 5 times the amount of current it has been designed for. The test is carried out by an electrician using a calibrated equipment. This test is always done during an electrical inspection to determine whether the RCD would cut off power fast enough to prevent shock.

When an RCD test is carried out, it ‘trips’ the RCD, disconnecting the circuit it protects. Any electrical equipment, therefore, needs to be disconnected before carrying out an RCD test. The test only takes about 5 minutes. In an office setting, it is advisable to do RCD tests prior to office opening hours otherwise you will have to inform your staff that there will be power disruptions.


Why should you test RCDs?

Old wiring and electrical appliances could have some earth leakage. Earth leakages are common in electrical systems. Whan you add more electrical appliances to your system, the earth leakage increases. Since earth leakages trips RCDs, excess tripping could lead to a circuit overload. Overloading of circuits causes electricity fatalities like fires or personal injury. RCD testing provides a means of early fault detection and helps avoid such electricity faults.


And are RCDs reliable?

According to a study published on http://carelabz.com/learn-about-residual-current-device-testing-safety/, RCDs have been found to be 97% reliable. Their reliability is even higher when they are tested regularly. However, RCDs don’t eliminate all electricity risks and great care should still be observed with electricity systems. To ensure your property is secure, have the wiring checked at least once every 10 years.



You should have professional electricians perform RCD tests on your property annually. You can rest at ease when you now that your family, workers and property are safe from electrical risks. We have expert electricians who do RCD testing in Manchester and beyond. Our electricians will advise you on the most effective measures to be taken if your RCDs are faulty.

Leave a Reply

Your email address will not be published.

You may use these <abbr title="HyperText Markup Language">HTML</abbr> tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <s> <strike> <strong>