Breakers as Switches - Good Idea?

At 08:55 18 February 2016, Jim White wrote:
At 17:17 17 February 2016, Steve Koerner wrote:
I think the right way to look at this is to take a gander at the spec
sheet=
of the referenced part. At the top of the sheet is a table showing the
re=
sistance that the breaker introduces for varying current ratings. It
shows=
for example that a 5A breaker introduces 0.03 ohms. Next, consider
the
p=
eak load of the device that you're powering. If it's a radio, for
example,=
look at its transmit current. Let's say the peak current is 1 amp.
Then
=
the voltage drop across the breaker is: V =3D iR =3D (1)(.03) =3D 30 mV

=
That's insignificant. The actual effect on battery life is that it will
mo=
re likely be extended by the introduction of the additional load; it's
just=
that the drop out point for the connected instrument will be 30mV lower

=
For a lithium battery with a fairly sharp fall off, I think you'll
normally=
end up net positive to battery life by the introduction of the small
serie=
s load (as long as the connected instrument works down to the steep part
of=
the battery discharge curve). =20

And, BTW, fuses have resistance too -- it's the same game with a fuse.

I was using ETA 106-P30 trips that have internal resistance of 0.9ohm fo
the 1a and 0.05 for the 5 amp. The problem was my Becker radio which onl
likes to work at 12V+. The 5amp breaker dropped the voltage by over 1V o
transmit which for SLA batteries made it unworkable. A standard blade fus
had much less impact.

I now use LifePo4 so this is now a mute point. However one point to not
with trips is the trip time. Mine were 10 seconds at 2x rated load
Standard fuse trips much faster.

If your Becker wont work below 12v there is something odd.

What model is it? The spec for AR6201 (25/8.33KHz) is: Input Voltage
Range: 9 V DC to 32.2 V DC

http://www.becker-avionics.com/ar620...with-8-33-khz/