On Sat, 07 May 2005 21:44:17 GMT, "Roger Long"
wrote:


I've already decided to run both my batteries as close to parallel as
possible to minimize the depth of the discharge cycles and get maximum
life out of the expensive AGM cells. This goes against the
conventional wisdom of always maintaining a dedicated starting
battery.

Modern electronic equipment can cause some annoyance/inconvenience
when powered from the same battery as used to start the engine.

When you start the engine, the battery voltage will drop significantly
- this may be enough to turn off depth sounders and other things that
have "soft" (electronic) power switches, and may cause
microprocessor-based equipment to reset - your GPS may have to start
from scratch re-acquiring satellites, and the radar will have to go
through the 90 second warm-up routine again.

Whether this is a serious problem, minor annoyance, or insignificant
will depend on the equipment on board, the circumstances, and on the
user....



--
Peter Bennett, VE7CEI
peterbb4 (at) interchange.ubc.ca
new newsgroup users info : http://vancouver-webpages.com/nnq
GPS and NMEA info: http://vancouver-webpages.com/peter
Vancouver Power Squadron: http://vancouver.powersquadron.ca

After all the crap with the Capn and other trolls, it's nice to have a
discussion going on here where solid information comes back.

My electronics outfit is pretty minimalist and the starting loads
about as small as they get. Starting from the two battery bank
shouldn't produce much drop with this little engine. This is
confirmed by someone who has been running the same kind of boat for
ten years this way.

However, before installing radar or a hard mounted GPS, I will
consider that adding a dedicated starting battery is an essential part
of the installation.

On this boat, I think I would go with the smaller size battery used in
aircraft. If they will start the 320 cubic inch, 160 hp, engine in my
172, they ought to get this little diesel going.

--

Roger Long



"Peter Bennett" wrote in message
news.com...
On Sat, 07 May 2005 21:44:17 GMT, "Roger Long"
wrote:


I've already decided to run both my batteries as close to parallel
as
possible to minimize the depth of the discharge cycles and get
maximum
life out of the expensive AGM cells. This goes against the
conventional wisdom of always maintaining a dedicated starting
battery.

Modern electronic equipment can cause some annoyance/inconvenience
when powered from the same battery as used to start the engine.

When you start the engine, the battery voltage will drop
significantly
- this may be enough to turn off depth sounders and other things
that
have "soft" (electronic) power switches, and may cause
microprocessor-based equipment to reset - your GPS may have to start
from scratch re-acquiring satellites, and the radar will have to go
through the 90 second warm-up routine again.

Whether this is a serious problem, minor annoyance, or insignificant
will depend on the equipment on board, the circumstances, and on the
user....



--
Peter Bennett, VE7CEI
peterbb4 (at) interchange.ubc.ca
new newsgroup users info : http://vancouver-webpages.com/nnq
GPS and NMEA info: http://vancouver-webpages.com/peter
Vancouver Power Squadron: http://vancouver.powersquadron.ca