I had an extension built and electrician fitted low voltage lights. Lights flickered so I changed them to the spot lights that worked direct from mains, with no need for a transformer. Changed most of them a year ago and then went to change the final 4 today. No problem with 3 of them as merely copied what I had done previously.
Got to the fourth, nearest the switch and it had a junction box with three wires. Disconnected the box without recording what connections were.
Looked at the various wiring diagrams on the net and worked out that the three reds needed to all be connected to each other. Closed off the three earths. Then turned to the three blacks. Guessed which Black came from the switch, connected this to the live for the light, and connected the other two blacks to the neutral for the light - guessed wrong so fuse blew.
Swapped blacks and this time lights stayed on permanently and switch didn't turn them off and on. Swapped blacks again and this time one light goes off and on when turn switch, but all other three stay on.
Any one any bright ideas as am running out of fuse wire.