I bought a 12volt 8.5amp TDK Lambda power supply from Radio Spares to replace a Mean Well 12v 8.5a supply which had failed after 3 years.
I connected it up to a 3 pin plug with a 13A fuse. When I plugged it in to an extension socket, which had a 13amp fuse, to check the output voltage, it tripped the CU , and the said extension socket blew the fuse. Any ideas as to why.
Thanks
MCB or RCD?
I don't know, how can I tell.
It's a Concactum DDS10166-P01 CU, just installed about 18 months ago
Does the individual breaker that tripped have a "test" button on it?
Yes it does, about 40mm to 70mm from the right hand side
Implies earth leakage from the power supply, nothing rattling around inside the PSU, or stray strands of wire where it's been connected? (could also explain it blowing a fuse)
No, nothing is rattling around inside the PSU, and the 3 core mains cable is securely screwed up in the 3 separate connections for +V ,-V and GND.
Err shouldn't it be wired to L, N and GND?
Ok but on the front of the psu is hows +V, -V then GND , then L and N That's from left to right. Have I wired it wrong , and it should be L,N and GND, doh!
That's what I saw on the RS photo
sounds like it, presume it now has "that smell"?
Well, I wasn't talking about the order of the connections, merely their labels, you should have brown to L, blue to N, and green/yellow to GND
with perhaps red(?) to +V and black(?) to -V on the output side.
No couldn't smell anything as the CU tripped immediately I plugged it in . I'll re do it and try again later now.
Wiring it L,N and GND helps. It powers up ok, but there is no output so something has gone on the inside when I wired it incorrectly.
I would have said I wasn't surprised it died ... except if I read the specs correctly it should withstand 500V AC applied to the output for 60 seconds? Maybe that's only when applied from +V to GND, not +V to -V
Me too actually, and thanks for your input
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