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Andy Wade wrote:
wrote:

it doesnt at all. Look for a bad connection or too many bulb watts for
the transformer. Bear in mind multimeters may read the 12v wrong if its
not sine wave.

The problem here is caused by the inductance of the cable, which I
figure will be roughly 0.9 uH per metre. For a 3 m run that's a
reactance of about 2 ohms at 125 kHz, so with the 3 A load current
mentioned the voltage drop will be about 6 V - more or less as observed :-)

The only solutions are to get the electronic 'transformer' nearer to the
luminaires, or use a real 50 Hz (iron-cored) transformer.

if its 2 core cable the L shuold be vanishingly small, as i is flowing
in opposite directions in each core. How do you get your 0,9uH figure?

NT