Homestead mailing list

[Don Bowen <don.bowen AT earthlink.net>]

At 6/1/2005, you wrote:
> > I cannot see using solar as a stand-alone system. My planer has a five 
> > horsepower motor. Batteries would never handle the starting load.
>
> Do batteries start your car?

Very different loads and batteries.  To start an AC load such as a 
synchronous motor, you have to contend with huge inrush currents before 
back EMF increases the load and reduces the current.  The high starting 
loads add to the power requirements.  Inverters are sometimes designed to 
handle those surge currents but they do drag the battery into low 
voltage.  Sometimes the inverter will see this low voltage and shut down.

Deep cycle and marine batteries are designed for steady current drain to 
get maximum capacity.  SLI (starting, lighting, ignition) batteries are 
designed to generate large amounts of current quickly then just as quickly 
recharge.  The starter motor is a fractional horse power motor so has 
smaller inrush currents, also as both field and stator coils are energized, 
back EMF builds much more quickly.

Don Bowen                          Awl Knotted Up

My travel journal
http://www.braingarage.com/Dons/Travels/journal/Journal.html

My present location is the star on the map in the link below
http://www.mapquest.com/maps/map.adp?latlongtype=decimal&latitude=33.506083&longitude=-117.099019