I have the old Gates energy manual on SLA. You can float charge them
all day, all night, until the cows come home, and even then keep them
on the float. In fact, the best thing to do for these batteries is to
float them. [AS you probably know, the risk with the used batteries is
they sat around too long. I check the no load voltage before buying.]

Cyclic chargers will get you back up to full charge faster than a
float.
Eric F. Richards wrote:
wrote:

That is the usual street price. Fry's stocks the NP4-6, slightly
larger, for $11.99.

I still think the used data center batteries are the way to go. Higher
capacity and about 20 cents on the dollar. You guys are really trying
to complicate matters. Just hit the ham flea market and somebody will
be selling these batteries. A bench supply should be about $20. No need
for the cyclic charger. The bench supply will be linear, so it doesn't
generate noise other than the usual diode on the mains.



Agree with the batteries statement, but not with the charger
statement. My 800 AH bank has been put together from pulls out of
hospital equipment bought at hamfests. $20 for 80AH gel cells? Can't
beat it with a stick.

However, gel cells are delicate and should be handled carefully during
charging -- delicate in that an improper charge will destroy them.
I'd use a proper charger with temperature compensation rather than a
bench supply -- I have an el-cheapo bench supply that wouldn't take
kindly to the load a heavily discharged battery would put on it,
anyway.

Both my solar charge controller and my (almost never used) 120 VAC
charger are PWM types that do a nice fast job of charging but know how
to handle gel cells.


Yodar wrote:
YUASA NP3-6 6V 3.0Ah sealed rechargeable lead-acid battery. This is one
of the most popular reliable 6V lead acid batteries around. This battery
is found in all types of equipment. Rated 6V 3.0Ah, the batteries we
have are new, full power units. They were to be installed into a product
so the manufacturer placed 2 strips of "hook and loop" fastener material
on one side, however this doesn't effect the battery and it probably
could be peeled off (however the adhesive is strong). This battery sells
elsewhere for up to $30 each. Remember these are original YUASA not "off
brand" batteries! G15560

http://www.goldmine-elec-products.co...em=1&mite m=1

FWIW

Yodar

--
Eric F. Richards

"Nature abhors a vacuum tube." -- Myron Glass,
often attributed to J. R. Pierce, Bell Labs, c. 1940