My parents had a whole medical office fitted out with 12 V halogen lights in 1987, three 400 VA transformers. All the light switches are on the secondary side, no fuses anywhere to be seen. The choc blocks between the 2.5 cables from the transformer and the leads on the lights kept melting and shorting until my dad replaced them all with ceramic. One short even fused the switch closed. Suspended plasterboard ceiling with plenty of acoustic insulation obviously made matters even worse and the metal grid was perfect for the bare connectors to short to. These days it’s all LED but everything else is original. Obviously the transformers are now incredibly oversized but surprisingly enough the LEDs cope just fine.

