Last year I opened the case of the controller of a failed set of decorative lights.
There was no isolation between mains input and the output to the lights, One side of the lights was connected to the Neutral, the other side was connecteed to the Live via a device which I guess was a high voltage MosFet transistor. An 8 pin IC controlled the MosFet. Two capacitors, a resistor and a zener diode supplied the IC with a supply.
The only saving grace was that the LEDs were enclosed in a tough plastic tube and thus well insulated.
There was no isolation between mains input and the output to the lights, One side of the lights was connected to the Neutral, the other side was connecteed to the Live via a device which I guess was a high voltage MosFet transistor. An 8 pin IC controlled the MosFet. Two capacitors, a resistor and a zener diode supplied the IC with a supply.
The only saving grace was that the LEDs were enclosed in a tough plastic tube and thus well insulated.
