Question about Cambridge Soundworks BassCube 8 Speaker

# The line fuse blows on power up. Input impeadance to the power transformre is 3 ohms. Is this correct? seems low.

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Ohms law I=V/R which is 240vac divided by 3 ohm = 80 amps. Dead short which is either the windings, or the mains filter capacitor which has gone short circuit which is more the likely culprit. This is on the output side of the fuse. If you have a meter switched to ohms and measure across this capacitor you will read zero ohms (dead short) which confirms the capacitor. Disconnect one side and if the short goes, then it's the cap, if not, it's the transformer.

Posted on Sep 12, 2009

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