Channel: John Ward (1)

Category: Science & Technology

Tags: ei electronicssmoke alarmlighting circuitaicowiring

Description: A straightforward replacement of a smoke alarm revealed that it wasn't connected properly, and it only had power when one of the two light switches was in a particular position, independent of the light being on or off. Property is about 20 years old, this problem may have been there for the whole time. The old smoke alarm had obviously been removed from the backing plate many times to presumably replace the battery, as it would have often been without mains power.