Auto-reclosing RCD and selectivity in Seville, Spain: stop the whole house tripping

Auto-reclosing RCD in Seville: so one trip does not cost you the fridge or the business

The RCD (residual current device, or GFCI in American English) trips when it detects a leak, and that is how it should be. The problem comes when it trips because of a passing disturbance, a distant storm or a spike on the grid, and there is nobody at home or in the shop to switch it back on. Hours later the fridge has warmed up, the cold room has spoilt the stock or the pump has left the house without water.

An auto-reclosing RCD solves that case: an auto-reclosing device checks that the leak has gone and switches the protection back on. And good selectivity prevents the other big headache, a fault on a single circuit switching off the whole house or business.

What an auto-reclosing device does

1. It detects the trip of the RCD or the circuit breaker.
2. It waits a few seconds and checks the insulation of the installation.
3. It recloses if the leak or fault has gone.
4. It locks out if the fault persists, after a limited number of attempts, so as not to force an installation with a real problem.
5. It sends an alert, on models that include it, to your mobile or to the home automation system.

When it is worth fitting

• Second homes and houses left empty for periods, in the Aljarafe, the sierra or on the coast.
• Homes with a full fridge and freezer, especially in summer.
• Bars, restaurants and shops with cold rooms, as we explain on our page for bars and restaurants.
• Well pumps, booster pump sets, servers and equipment that must not stop.
• Areas with frequent storms, where trips caused by disturbances keep happening.

If the tripping is constant, an auto-recloser is not the answer: there is a leak or an unsuitable RCD. We solve that first with a high-immunity RCD or by repairing the leak, as we explain on RCD keeps tripping.

Selectivity: only what fails should trip

A fuse board with good selectivity works like a chain of staggered protection: when there is a fault, the nearest device trips and the ones upstream hold. To achieve it:

• We stagger ratings and curves of the circuit breakers (MCBs) between the main switch and each circuit.
• We stagger sensitivity and time of the RCDs, with a time-delayed (selective) RCD at the head when there are several in cascade.
• We share the circuits between several RCDs, so a leak on the terrace does not switch off the fridge and the router.
• We separate what is critical: refrigeration, pumps, servers and alarms on their own circuits.

Regulations

• ITC-BT-17: main and individual control and protection devices in the board.
• ITC-BT-22: protection against overcurrent, which sets how circuit breakers must be sized.

Auto-reclosers in the Aljarafe, the countryside and Seville’s businesses

We fit them mostly in villas and second homes in the Aljarafe, from Mairena to Tomares, Bormujos and the towns in the north and south of the area, in country houses around Carmona, where a stopped pump leaves the house without water, and in bars and shops in the city centre and Dos Hermanas with cold rooms. In many cases we add surge protection, because storms are the most common cause of passing trips, and energy monitoring that alerts you if something stops working.

How we work

1. Check of the fuse board and the existing protection devices.
2. Insulation measurements to rule out real leaks.
3. Proposal: auto-recloser, reorganising circuits or both.
4. Fixed quote.
5. Installation and test of the reclosing and the selectivity.
6. Setting up mobile alerts if the device includes them.

If your board has no room to reorganise, see fuse board replacement.

Guide prices

More references on our prices page and the rest of our protection services under electrical safety.