Residual Current Devices, or RCDs, are essential safety devices that protect people from electric shock and prevent fires caused by electrical faults. They work by cutting off the power the moment a fault is detected.

Whether your property is a school, office, factory or public building, RCDs are critical and regular testing is a legal requirement under BS 7671:2018.

Why Is RCD Testing Important? 

RCDs can degrade over time or develop faults without any visible warning signs. If a device fails to trip when it should, the consequences can be serious.

Regular testing ensures your site remains legally compliant and that your people are protected from unnecessary risk.

How Often Should RCDs Be Tested? 

There are two levels of testing to be aware of. 

A user test involves pressing the test button every six to twelve months to simulate a fault and confirm the device trips as expected.

An engineer test is a full functional test carried out by a qualified electrician annually or in line with your risk assessment. This measures trip time, response accuracy and identifies any underlying issues. 

If your RCD does not trip when the test button is pressed, trips too frequently for no clear reason, or causes unexpected power cuts to appliances or circuits, it needs attention. Our team can assess and advise on the right course of action. 

What We Offer 

We carry out full RCD testing with clear, readable reports that identify exactly what needs attention. We also provide complete RCD mapping so you have a full picture of each device, what it controls and which board it belongs to. 

RCD testing can be combined with EML and PAT testing to reduce the number of site visits and keep costs down. 

About TISS Electrical 

Our engineers work across commercial and industrial sites of all sizes and understand what proper RCD compliance looks like in practice. We keep the process straightforward and make sure you have everything you need to stay on top of your obligations. 

Our RCD testing services are available throughout Suffolk, Essex and Cambridgeshire. Whether you are based in Balsham, Felixstowe, Bungay, Haverhill, Brightlingsea, Wisbech, Wrabness, Beccles, Halesworth, Sawston, Bury St Edmunds, Cambridge, Clacton, Ely, Mistley, Sudbury, Teversham, Wivenhoe, Trimley St Mary, Chelmsford, Peterborough, Basildon, Brentwood, Cambourne, Marks Tey, Stowmarket, Ipswich, Burwell, Tiptree, Harwich, Cottenham, Bar Hill, Manningtree, Walton, Woodbridge, Waterbeach, Halstead, Mildenhall, Great Bentley, St Ives, Linton, Saffron Walden, Leiston, St Neots, Lawford, Great Shelford, March, Frinton, Bures, Soham, Hadleigh, Brandon, Braintree, Kesgrave, Lowestoft, Newmarket, Huntingdon, Fulbourn, Needham Market, Colchester, Milton or Histon, get in touch with our team. 

For full details about RCD Testing, please visit here. 

Contact Us

To book RCD testing or find out more about what is involved, get in touch with our team. You can reach us by email at [email protected] or by phone on 01245 377 625.