On Jun 26, 9:55 pm, Chris <cfoley1...@[EMAIL PROTECTED]
> wrote:
> On Jun 26, 8:04 pm, lili...@[EMAIL PROTECTED]
wrote:
>
>
>
> > On Jun 26, 6:23 pm, Peter Bennett <pete...@[EMAIL PROTECTED]
> wrote:
>
> > > On Thu, 26 Jun 2008 14:09:18 -0700 (PDT), lili...@[EMAIL PROTECTED]
wrote:
> > > >On Jun 26, 4:43 pm, mrdarr...@[EMAIL PROTECTED]
wrote:
> > > >> On Jun 26, 1:16 pm, lili...@[EMAIL PROTECTED]
wrote:
>
> > > >> > On Jun 26, 4:10 pm, mrdarr...@[EMAIL PROTECTED]
wrote:
>
> > > >> > > On Jun 26, 12:20 pm, lili...@[EMAIL PROTECTED]
wrote:
>
> > > >> > > > Hello everybody,
>
> > > >> > > > I have a set of battery, but I only one hooked up to the
circuit, The
> > > >> > > > other one act as a backup. I want to implement an
electronic unit that
> > > >> > > > will change (swap) the batteries.Therefore the wiring will
need to be
> > > >> > > > changed. The circuit need to sup****t 5amp of continuous
current. Here
> > > >> > > > is what I want to implement.
> > > >> > > > from:
> > > >> > > > A to C
> > > >> > > > B to D
>
> > > >> > > > to:
> > > >> > > > A to D
> > > >> > > > B to C
>
> > > >> > > > Is it better to use a analogue or digital switching
approach. I am
> > > >> > > > just worried that digital might take too much energy by
keeping those
> > > >> > > > transistor or mosfet open and close.
>
> > > >> > > > Li
>
> > > >> > > You mean something like this? (view in fixed-width font, for
example,
> > > >> > > with Notepad)
>
> > > >> > > +---+ +----+ +---+
> > > >> > > |(+)|--switch A--| |--switch C--|(+)|
> > > >> > > | | |Load| | |
> > > >> > > | | | | | |
> > > >> > > |(-)|--switch B--| |--switch D--| |
> > > >> > > +---- +----+ +---+
>
> > > >> > > Batt 1 Batt 2
>
> > > >> > Michael, This is basically what I want to do.
> > > >> > The battery will run a very small motor and a light.
>
> > > >> > Li
>
> > > >> Looks like a double-pole-double-throw switch will work
>
> > > >> see http://en.wikipedia.org/wiki/Switch
> > > >> look under DPDT
>
> > > >> seems simpler than a MOSFET solution.
>
> > > >> When exactly do you want to switch?
>
> > > >> Michael
>
> > > >This was one of the initial idea, Maybe have a servo motor to
control
> > > >the switch. ( and a PIC chip to supervise the whole operation)
> > > >K
>
> > > Use a relay - that's an electrically controlled switch.
>
> > > There is probably no need to switch both positive and negative
> > > terminals - using an SPDT switch in the positive leads would likely
be
> > > sufficient.
>
> > > An output of a PIC probably won't drive a 5 amp relay directly, so
you
> > > would have to have the PIC drive a transistor or small relay, which
> > > would drive the large relay.
>
> > > --
> > > Peter Bennett, VE7CEI
> > > peterbb4 (at) interchange.ubc.ca
> > > GPS and NMEA info:http://vancouver-webpages.com/peter
> > > Vancouver Power Squadron:http://vancouver.powersquadron.ca
>
> > would there be anything else beside a relay?
> > that would require energy only when switching is required?
>
> > Li- Hide quoted text -
>
> > - Show quoted text -
>
> Try looking up a "latching relay". They only require power when
> they're switching. Driving a 5A load is going to require a realy with
> at least a 1 watt coil, so you'll need two transistors to drive the
> two coils from the PIC.
>
> Cheers
> Chris
Hi,
That seems to be a good idea. I found this part SP4-L2-DC12V at
digikey. But I have not seen any latching relay able to sup****t 6 amp
or something like 740watt (1 HP)
Li
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