I have a problem with one of my wall lights- the bulb keeps blowing. It was fine until a few weeks ago when the 5A circuit fuse blew. I replaced the wire in the fusebox and bulb and everything was ok for a day or two then the bulb blew again. The fuse has not blown since, but I've got through about 5 bulbs (of different manufacturers). Checked the bulb holder and cleaned up the contacts- no obvious signs of arcing. All contacts are tight. Checked the switch- all contacts good.
However, on the switch (which is being used as SPST x 2), one of the black neutral wires is unconnected- is this correct? One live (red) goes to the common on switch 1, the black (neutral) goes onto L1 on switch 1. Common on switch 1 is bridged to common on switch 2. L1 on switch 2 is then connected to the other red (live) and the other black remains unconnected.
Any ideas/help would be greatly appreciated.