Is your Ring really a Ring?
Most homes will have at least one Socket circuit, if not more, and typically these are connected as a “Ring”, sometimes your Consumer Unit will have the reference “Ring” or “Socket Ring” or “Power Ring”. The wiring regulations classify a ring circuit as:
“A ring final circuit starts and finishes at the distribution board [Consumer Unit / Fuse Box], where it is connected to a 30A or 32A overcurrent protection device [MCB / Fuse].”
Which basically means a piece of cable leaves your Consumer Unit, goes in and out of several sockets and then returns to the Consumer Unit – completing the “ring”.
Most faults we find whilst carrying out Periodic Electrical Inspections are ring-circuit related, and typically we find that “Ring” circuits are no longer a “Ring” anymore.
Is this dangerous?
Simple answer is YES, very! Quite simply a “Ring” circuit is designed to share the load all around it, and by interrupting the ring your power circuit is in risk of overloading the cables supplying it, this can lead to cable failure (melting) and possible fire.
Will my MCB / Fuse trip if this happens?
No! Your MCB / Fuse will be rated at 30A or 32A, which is the rating for a power ring circuit, if your ring is broken, then the maximum load drops to 20A – therefore the MCB / Fuse will NOT trip and cable failures can easily occur.
What causes a “Ring” failure?
Assuming the original wiring of your home as been correctly installed and tested, then its typically external influences cause failure, most common faults are from:
- Replacement socket outlets where connections become loose
- Joint boxes where the connections fail / become loose
- Cables which have been extended with non-permanent connections
- DIY / Building works which has damaged a hidden cable without notice
- Rodent damage
How do I know if my “Ring” is broken?
You don’t – and many “Ring” problems go unnoticed for many years. Thankfully a good Periodic Electrical Inspection will detect this – our electrical testers are built with high-impedance ohmmeters which can detect ring continuity faults and our engineers can best advise on the correct remedial method to ensure protection & safety.
If your home is due a Periodic Electrical Inspection or you would like an Electrical Inspection carried out by a professional inspection specialist, please contact us.
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