+1
What Chuck said.
I did talk some with an engineer at MidNite Solar about using one of
their controllers this way. His comments were similar to what Chuck
said. One, you want a power supply that can supply enough current to
power the equipment, plus enough to charge the batteries at whatever
their bulk charge rate is. Two, you want a power supply with a current
limit because solar panels will self-limit at whatever their maximum
current rating is, and you don't want the solar controller to "go over"
in an attempt to find the maximum power point.
I'm assuming you would be using an MPPT controller of some kind. The one
that I was looking at was the "Kid" from MidNite Solar. That particular
controller I liked because (1) It would handle almost any battery
voltage up to 48V, (2) It could handle charge currents up to 30 amps,
and (3) would handle input voltages up to 150V.
bp
<part15sbs{at}gmail{dot}com>
On 3/15/2015 8:31 PM, Chuck McCown wrote:
Any charger with decent current limiting will do the job. You want a
power supply that will pull the load plus the low battery current, so
at least twice the load current probably would be a minimum. What
load and how big are your batts? Normally you would want to have a
current of at least 10% of the amp hour rating available to charge
plus the load current. But if the batts are really really dead, it
may be a while before the voltage comes up to an operational level.
*From:* TJ Trout <mailto:t...@voltbb.com>
*Sent:* Saturday, March 14, 2015 4:53 PM
*To:* af@afmug.com <mailto:af@afmug.com>
*Subject:* [AFMUG] Dc power supply + solar controller for cheap dc ups?
What do I need besides a dc power supply to be able to have a dc ups
with the ability to charge batteries and have seemless transfer to and
from batteries when ac fails as well as limiting on the batteries
being charged so the charging doesn't over run the current of the psu
once the ac comes back ? Aka poor man's ups? Dell nps700ab poweredge
supplies are 12v 700w for like 5 bucks
