[aprssig] backup pwr systems
ve7gdh at rac.ca
Sat Dec 9 13:15:17 CST 2006
Charles N5EXY wrote...
> FWIW I had two "smart" chargers (different brands)
> fail and boil two relatively new deep cycle batteries
> dry. Even the smart ones need to be monitored a bit.
What make and model were the "smart" chargers? Yes, if it isn't a
"maintenance free" battery such as AGM or gel, you do need to keep the level
up by topping it up with distilled water, but the levels shouldn't go down
much unless you are deeply discharging the battery and then charging it a
high rate all of the time. A true "3 stage charger" should charge the
battery at the (bulk) maximum rate, and then change to a fixed voltage at a
certain point, and then it should switch again to a lower voltage to trickle
charge the battery for maintenance. The charger type should match the
battery chemistry. Some batteries (flooded lead acid) should get the
occasional equalization charge at a higher rate to shake things up. With the
wrong charger, or one that isn't as "smart" as advertised, battery life will
be impacted. I've actually got a large battery bank that is down in capacity
right now. I'm playing around with a battery desulfator to see if it can
recover some capacity.
My backup power system is to keep computers (and other things) running. Just
to keep it on topic, it also powers a digi / IGate / IRLP node and other
things. Disasters like Katrina show how important it is to have a backup
power system. However, that was on such a massive scale that most backup
power systems would be severely taxed, but having some backup capability is
better than no capability. Most of my power outages are from wind or snow in
winter. Most are of short duration... less than 3 hours. However, an outage
of nearly a week is not unheard of. Here in southwest BC, we had nearly two
weeks of high winds and heavy rain, followed by a week and a half of snow
(OK, two days of snow, but it hung around a while) and cool temperatures
with some lengthy outages for some areas. Each individual should decide how
much of a "backup power system" they need and go from there. Some will opt
for none. Others will have a 60-100 Ah battery and a smart charger and
connect it when needed. Others will go for a lot more capacity and automatic
changeover. Some will have solar power and/or generator backup as well.
There are lots of options to choose from. Looking at it from the APRS
perspective, keeping digis and IGates running during power failures could
really make the difference between having no communications and some
communications. Of course, voice repeaters would certainly benefit from
backup power capability as well, as would HF stations.
73 es cul - Keith VE7GDH
"I may be lost, but I know exactly where I am!"
More information about the aprssig