Auto-recloser (rearmador automático, automatic reset device)

How an auto-recloser works

It is mounted next to the protective device, usually an RCD (diferencial). When the RCD trips, the recloser waits a moment, checks there is no permanent fault and switches it back on. If the fault persists, it tries a few times and then locks out, leaving the circuit open. So it does not cancel the safety function: it only deals with one-off trips.

When it is worth fitting

• Second homes. A storm or an isolated trip does not leave the fridge and freezer off until your next visit, which matters if you spend part of the year away.
• Fridges, freezers and cold rooms in homes and in bars and restaurants, where a night-time trip can ruin stock.
• Alarms, cameras and smart home systems that must stay on.
• EV chargers, so a single trip does not leave you without charge in the morning.

What it does not fix

If the RCD trips often, the recloser only hides the problem. The earth leak or faulty appliance has to be found first. If the trips come from electronics, LEDs or dimmers, a high-immunity RCD may be the answer. Good selectivity between devices also helps, so one fault does not black out the whole home.

Rough price

An auto-recloser costs 150 to 400 euros fitted, plus VAT, as a guide, depending on whether it is for an RCD or an MCB and on the space in the board. See auto-reclosing RCD and RCD keeps tripping in Seville, Spain.