Electrical

3 black wires in ceiling rose, which is L and N?

Anonymous user 28/02/2024 - 3.56 PM

2 part question Replacing front room light. I didn't notice until I went to put up new light that there are 3 black wires - 2 together and a single. Which way round is L and N? Or does it not matter? The switch has only 2 blue wires. These 3 black cables seem to be all sheathed together in black. And they connect into connector strip with no allowance for a loop. Second part. The fact that there are 3 wires would explain the dodgy wiring we've only just noticed. My porch light goes on and off BUT when you turn the front room light on it turns off and the switch does nothing until you turn the front room light off again. The Hall three-gang switch controls the the hall lights (up and down) individually – both two-way, and the porch. The switches are wired as follows: Switch 1 (Hall Down) L2 = Blue, Red, Red (to switch 3 Common) L1 = 2x Red Common = Yellow Switch 2 (Hall Up) Common = Yellow L1 = Blue L2 = Red Switch 3 (Porch) L2 = Red L1 = Empty Common = Red (from switch 1 L2) Switch 1 & 2 have a two-way switch upstairs so you can turn on/of either hall light from either up/down stairs. Switch 3 should ONLY turn on/off the porch light, this is a one-way switch. Clearly there is some cross wiring as the front room switch (completely different room) should not have any affect on switch 3.