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<DIV><FONT face=Arial size=2>+S must be connected to +5V and -S must be
connected to GND preferably at the load but okay at the power
supply.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>See if the transformer primary has an internal
short to ground.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>A 1A fuse in the primary implies that the power
supply can draw upto 120 watts. At 50% efficency 60 watts for load.
Plenty.</FONT></DIV>
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<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A title=krhen@stucki.com href="mailto:krhen@stucki.com">Rhen, Kris</A> </DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A title=synth-diy@dropmix.xs4all.nl
href="mailto:synth-diy@dropmix.xs4all.nl">'SynthDIYmailinglist '</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Monday, December 10, 2001 2:43
PM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> [sdiy] The Next Newbie Power
Supply question...</DIV>
<DIV><BR></DIV>
<P><FONT size=2>I've got a +-12v, +5v regulated power supply which is acting
odd (or more likely I just don't understand what's up with it). Wired it
up to take AC through a standard plug, one of the non-ground leads goes
through a fuse (in this case a 1A fast-blow fuse, even though the supply goes
to 1.5A I'll never draw that much from it). The other end of the fuse,
as well as the other non-ground lead from the input goes to the supply.
I take the ground and connect it to the case as well as the GROUND output lead
(of which it has two) Power it up as-is and its great, I get my +12v,
-12v and +5v relative to the ground just fine.</FONT></P>
<P><FONT size=2>Now I run some wires from the GND, +5, +12 and -12 to a power
dist board and power it up with a switch on a power strip its plugged
into. Fuse blows with a nice flashy lightshow. I've gone through a
couple of fuses like this (note NO LOAD (Doepfer/As/AS modules) yet - and I
won't until I understand why they're blowing). Note its outputs
are</FONT></P>
<P><FONT size=2>-12v GND +12v
+5v +S -S GND</FONT> </P>
<P><FONT size=2>and I don't have the sensing hooked to anything.
</FONT></P>
<P><FONT size=2>Can anyone tell me (without shouting :-) why the fuse is
blowing? Again, gotta learn somehow and you all have been great
teachers. Thanks again</FONT></P>
<P><FONT size=2>KRIS</FONT> </P><CODE><FONT
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