Mains Smoke Alarms

Mains Smoke Alarms

Mains smoke alarms or mains powered smoke alarms are supplied with 230V from the mains wiring of a building. They can be wired into a special alarm wiring loop coming directly from the fusebox or they can be fed from the nearest light fitting. Supply from the light fitting is recommended and cheaper. However, care must be taken that the supply is not wired incorrectly and the smoke alarm is by mistake supplied by a 'switched' electric cable, otherwise low battery warnings might ensue. Mains smoke alarms with a form of interlink (wire interlink between units or radio-interlink) fulfil BS5839 part 6 grade D required for extensions, new domestic buildings, let homes, HMOs and many more applications.

Back-Up Batteries

All our mains powered smoke detectors and heat alarms have back-up batteries. This ensures that the smoke alarms are still working even if the mains power fails. These back-up batteries are either non-rechargeable (eg alkaline batteries), in which case they need replacing every year or two, or they contain sealed-in re-chargeable lithium back-up batteries which are re-charged with a trickle charge. Sealed-in batteries cannot be replaced at the end of their lifespan which is usually ten years.