On Wed, 2009-04-01 at 08:56 -0500, Hulett, Russell wrote:
> Hello Mike,
> As I read the datasheet for the 1.5KE15A, the breakdown voltage is nominally
> 15 VDC. So when the pass transistor shorts, won't the transient diode limit
> the voltage to the load to nominal 15 VDC, bypassing enough current to ground
> to trip the overload on the power supply?
Nominal at a particular current. Higher current from the supply the
voltage is higher, maybe a lot higher.
> I intend to incorporate a fast-blow fuse, not sure why the question prompted
> the sarcasm.
Until you get to the super fast silver element fuses, a fast blow fuse
is just a good indicator that the associated transistor has melted. E.g.
the lifetime of the overloaded semiconductor is shorter than the fuse.
> 73, Curt KB5JO
Then the added voltage drop of the fuse and fuse holder take away from
the desired power supply regulation.
73, Jerry, K0CQ
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