Transformers for 240V mains to 12V lights: I have several dead transformers (not sure what type exactly) hooked up in parallel to a domestic mains circuit. I can't easily get at them to change them, they're in a ceiling & I don't want to rip the whole ceiling down!
However, I can add new transformers (a spot of key-hole surgery) to the circuit, effectively bypassing the dead ones, and it's easy to rewire (new) lights to the new transformers. The old, dead transformers remain in parallel with the new ones. I will put the old12 V ends into connectors, for safety and tidiness.
Q1: What are the problems of simply leaving the old ones where they are in parallel with the new - any safety issues? Q2: Could the demise of the old transformers have been caused by replacing the switch with a dimmer - they worked initially. (The new transformers are all dimmable).