The fuse values are recommended by the manufacturer of the transformer and
we took them over without changes. We test all A-100 systems and frames that
are manufactured in our company with the full load (i.e. 650mA for the old
version of the power supply and 1200 mA for the PSU2). For empty frames we
use dummy loads (high power resistors) to simulate the load. So far we never
discovered a blown fuse during the final test (of course expect if there was
a fault) with the specified values.
As we have no "real" 115V mains voltage available in Germany we use a
230->115V transformer for testing the 115V systems and frames. Maybe the
"real" 115V mains behaves a bit different, as the 230->115V transformer
causes an additional delay until the full mains voltage is available.

In any case one has to pay attention of the blow type. In any case the slow
version (time lag) is necessary. Fuses with medium or fast response may blow
during power on! If you are sure that you use a time lag/slow blow fuse with
the right value (500mA for 115V and PSU2) you may increase the value to the
next step (630mA is the next common value here in Germany). This is OK as
even a 630mA fuse will blow in case of e.g. a short circuit.

In any case I have to warn against the usage of metal foils or other
conductive materials to short the fuse. It is OK to use a fuse with the next
higher value. But never short the fuse ! This is extremely dangerous and may
cause fire or other damages.

Best wishes
Dieter Doepfer

P.S. We have about 15 PSU1 left. When they are used up only the PSU2 will be
manufactured.

> -----Ursprüngliche Nachricht-----
> Von: Doepfer_a100@yahoogroups.com
> [mailto: Doepfer_a100@yahoogroups.com ]Im Auftrag von tkrakowiak
> Gesendet: Samstag, 17. Dezember 2005 22:03
> An: Doepfer_a100@yahoogroups.com
> Betreff: Re: 1 Re: fuse issue (Correction)
>
>
> hello,
>
> don't think it's shorting anywhere inside the suitcase (it's got
> composite-plastic walls and aluminum railings which shouldn't affect even
> when touched), but i'll check anyway. it seems to happen only when i'm
> taking it somewhere (that's why i asked about moisture buildup) , when it
> happened yesterday (2 fuses, 1 after another:) i only saw a blink
> of led on
> a119.
> soooo.... could i _safely_ try a different variety of fuses
> somewhat desperately looking for answers ( Dieter ).
> have a nice weekend all.
> cheers
> t
>
>
>
>
> > I'm not sure if this is the problem you are having, but some Doepfer
> > modules have PC boards *very* close to the edge of the module and it's
> > possible that the power traces are shorting out against your case.
> > This happened to me when I tried to install a certain Doepfer module
> > (either the Quad ADSR or Triple Bandpass, I can't remember which) in an
> > Asys RS15 euro-rack.... the traces on the lowest PC board touched
> > against the case and shorted out the whole system. The worst part is
> > that it fried 2 of my modules and I had to pay $180 to fix them.
> > Now I don't know if the Doepfer cases are the exact same dimensions as
> > the RS15, but you might want to check and see if any of your modules'
> > PC boards can touch the case under rigorous patching conditions.
> > Usually when a fuse keeps getting blown, there is an intermittent short
> > in the electrical system... or you are getting really bad power spikes
> > from your AC line. I assume you are using some sort of surge protector
>
>
> [Non-text portions of this message have been removed]
>
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