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Ian Stirling
 
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Default Low Voltage Lighting transformer problem

fred wrote:
In article , Ben Mack
writes
Hi

I've installed some 12V halogen lights in some shelves, such that I have
to mount the transformer remotely. I used 3m of normal 1.5mm^2 lighting
cable to connect the transformer to the lights, having calculated a
300mV drop across the cable (30mV/A/m x 3.3A x 3m)

However in practise I'm losing around 6V in the cable, and have
discovered that the transformer output is 125kHz, not 50Hz, explaining
the bad attenuation in the cable

Look for another cause to the problem, 100pF/m for the T/E over 3m still
gives 4k impedance at 125kHz so unlikely to be causing your 6V problem.
Look at minimum load, maximum load, wiring faults & faulty transformer.


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