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Discussion Starter · #1 ·
Can anyone help I'm trying to wire up a 12V DC Smoothed Power supply(Reference #EX/PS12) from express models I have followed the instructions but I cannot get any of the leds I have connected to it to work has any one got any clues anyone here using one them selves?

Pete
 

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Peter, from what I can see from the picture on Express Model's website there's not a lot you could possibly get wrong with that unit. It appears to a pairs of terminals for the AC in and a pair of terminals for the DC out. Not wishing to attempt teaching my grandmother to suck eggs but I presume you've connected the LEDs with the polarity correct? I think dbclass50's suggestion of proving an output from the unit with a meter or whatever does seem to be the best way forward.
 

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Discussion Starter · #4 ·
Well have put the AC in one end and the 12v connection in the other and I have it the write way round when I connect the AC the heat sink on it smokes it only did it once and only for about a second but no output at all I have checked the the circuits and the components and the all check out OK but no output.

I am connecting 16V ac from a Gaugemaster combi controller.

Pete
 

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Peter, I've just read my post again and must apologise for the lack of lucidity
but you obviously got the gist of it.

From your last post I don't think there's much doubt that the unit is defective - smoke being the clue!
. I don't reckon you've much choice now but to send it back to Express Models for repair/exchange. Any idea what sort of load you had connected to the DC output?. The only reason I ask is because about the only thing on that board that is remotely fragile is the fixed voltage regulator itself (the bit the heat sink is fitted to), and even these are fairly indestructible being that they usually have an integral overload protection.

Steve
 

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QUOTE (Peter_Harvey @ 19 May 2007, 21:54) <{POST_SNAPBACK}>Well have put the AC in one end and the 12v connection in the other and I have it the write way round when I connect the AC the heat sink on it smokes it only did it once and only for about a second but no output at all I have checked the the circuits and the components and the all check out OK but no output.

I am connecting 16V ac from a Gaugemaster combi controller.

Pete
If indeed you have connected up the device correctly then something is definitely wrong here! Are you certain you connected the AC from your gaugemaster to the correct terminals on the unit?
Semiconductor devices are the quickest blowing fuses known to man so I suggest that the regulator is cream crackered!
Also I presume that the LED on the output had the correct current limiting resistor connected in series with it?
 
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