Patrick,
Here's what I'm using in both my primary lines of
both of my power supplies, the 4-1000A and GS35B.
____________________________________________________
Part R@
SL32 0R230 0.25 30 100 200 0.008 0.018 45.4
194 A
--- Patrick Egloff <pegloff@gmail.com> wrote:
> Hello Mike,
>
> Are'nt those beasts a little bit too resistive under
> normal operating
> conditions and temperature ??
> According to the datas found on the page you
> provided, the lowest value is
> 0.5 Ohm, which is enough to produce a significant
> voltage drop with the
> current we use in our amps !
>
> What reference did you use in your amplifier and did
> you place this limiters
> in the transformer primary ?
>
> 73s (not limitied),
> Patrick
>
>
> 2008/2/7, aborg <a_borg@yahoo.com>:
> >
> > I guess I'll chime in with my limited input. Why
> not
> > use simple "Inrush Current Limter thermistors ? I
> use
> > them for my 4-1000A amp and my 7.5Kv power supply.
> > Very simple to install and ver efficient.
> Purchased
> > from Digi-Key,Mouser or even RF Parts.
> >
> >
> http://www.ametherm.com/Inrush_Current/welcome.html
> >
> >
>
*****************************************************
> > --- Ian White GM3SEK <gm3sek@ifwtech.co.uk> wrote:
> >
> > > Han Higasa wrote:
> > > >GM all
> > > >
> > > >As Steve told whatever loop (open or closed)
> has
> > > been chosen
> > > >a situation where a relay contact will not
> close
> > > and inrush-current
> > > >limitation resistor R will never be shorten can
> > > happen.
> > > >
> > > >To address this a "step-start duration" timer
> > > should be added;
> > > >and to monitor this a "step start duration
> timer"
> > > timer should also be?
> > > >
> > > >Instead, robust R and an operator can do this
> by
> > > perceiving
> > > >"it takes too long and the step-start never
> lasts"
> > > >
> > > >I am using a 30-ohm 100-W resistor for the R
> now.
> > > >I think I should disconnect my step-start delay
> > > timer and measure
> > > >the voltage across R in time elapsed, to make
> sure
> > > the R will not
> > > >barn out.
> > > >
> > >
> > > A much simpler solution is a slow-blow (T) fuse
> in
> > > series with the
> > > current limiting resistor. This idea has been
> used
> > > by Alpha and others
> > > for many years.
> > >
> > > The fuse rating can be about 25% of the
> long-term
> > > short circuit current,
> > > eg for 230V and 30 ohms it could be a 2AT fuse.
> If
> > > the normal step time
> > > is less than about 1 second, this fuse will
> never
> > > blow unless the
> > > step-start "hangs". The step-start resistor must
> be
> > > capable of handling
> > > the "hang" current (the steady value when the
> > > resistor is tuck
> > > permanently between the mains and the amplifier)
> for
> > > the several seconds
> > > that it takes to blow the fuse, but it doesn't
> need
> > > to be rated to
> > > survive forever - the fuse will protect it.
> > >
> > > Incidentally, most step-starts are much longer
> than
> > > they need to be, as
> > > the big current pulses only occur during the
> first
> > > few cycles of the
> > > mains. The aim should be to make the first and
> > > second current surges of
> > > equal size, so that neither one is "worse" than
> the
> > > other. A very long
> > > step time doesn't really help with this - it
> doesn't
> > > affect the size of
> > > the first current surge, and doesn't do much to
> > > reduce the second
> > > current surge, but it puts much more stress on
> the
> > > resistor.
> > >
> > >
> > > --
> > >
> > > 73 from Ian GM3SEK
> > > http://www.ifwtech.co.uk/g3sek
> > > _______________________________________________
> > > Amps mailing list
> > > Amps@contesting.com
> > >
> http://lists.contesting.com/mailman/listinfo/amps
> > >
> >
> >
> > Mike-KK4MS
> > a_borg@yahoo.com
> >
> >
> >
> >
>
____________________________________________________________________________________
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> > http://www.yahoo.com/r/hs
> > _______________________________________________
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> >
>
>
>
> --
> Patrick Egloff - TK5EP
> email : pegloff@gmail.com
> Fax : +33 826 698 954
> Web page : http://tk5ep.free.fr
>
Mike-KK4MS
a_borg@yahoo.com
____________________________________________________________________________________
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