Posted by DLC on June 21, 2011, 7:41 pm
My weekend cabin has:
42 watt Kyocera panel
2 100 amp hour Power Sonic Sealed Lead Acid Batteries
1 Morningstar Charge controller Sunsaver 10
I have just been given a riding mower that has a 12 volt battery that I
may need to charge from time to time.
Would there be any problem with temporarily connecting this battery in
parallel with the solar system batteries?
I do have a generator that I could use, but it seems a waste of fuel to
use it to charge this small battery.
Posted by Winston on June 21, 2011, 8:07 pm
Yes. Current flow could be a huge issue.
Suggest connect a battery charge controller to tailor the
charge current so that you don't damage your system.
Outgassing hydrogen and sparks mix *all too well*.
Posted by Jim Wilkins on June 21, 2011, 9:26 pm
What he said.
Can you disconnect the big batteries and charge the small one by
Posted by DLC on June 21, 2011, 11:18 pm
On 6/21/2011 4:07 PM, Winston wrote:
I can add a separate charge controller just for the mower battery in
parallel with the regular charge controller. Would that be sufficient?
The mower battery would not be in the same enclosure, so hydrogen
shouldn't be a problem.
Posted by Winston on June 22, 2011, 2:51 am
There isn't any power left for a second charge controller to use.
I suspect that your existing charge controller probably
could draw 4 times as much current as your PV panel is capable
of safely sourcing.
I believe you require a hefty DC timer driving one of these
charger circuits, powered by your Power Sonic batteries, to
charge your mower:
See their PST-BC1212-15 DCDC Chargercircuit.
It is not terribly efficient, but it would probably work
just fine as long as you don't leave your mower connected
for much longer than it takes to safely charge.