Re: cold start runaways
Posted: Sun Nov 05, 2017 7:02 am
PS Never leave a cheap "constant current" charger on any
battery unless you regularly monitor it with a voltmeter and
know when to take it off. Even a little 1 amp charger can
over-voltage and destroy your battery if you leave it on
long enough!
You need a "smart" or "constant voltage" (it isn't really, but)
charger which varies it's output current with the battery
voltage. Once the battery voltage gets high enough, it
drops it's charging current to avoid damaging the battery.
Here is what a "smart charger" voltage looks like:
[img width=500 height=333][/img]
Note that it charges up to 14.3 volts and then
shuts off. The battery slowly falls down and then
before sulfation can begin at 12.8V, it spanks
the battery again. Rinse, lather, repeat as the
shampoo bottle says.
There are many good brands of "smart" chargers,
such as CTEK, Genius and the original Battery
Tender, which I buy because they are simple and
cheap and do a great job of keeping a good battery
in good shape.
PS As I say to the kids at work, 30 years ago I
used to be an electrical engineer. Today, not
so much. I am amused, though, when people
mistake me for a hardware engineer. No, I write
software, but recently I had to explain to a young
fellow what
[url=https://en.wikipedia.org/wiki/Schmitt_trigger]https://en.wikipedia.org/wiki/Schmitt_trigger[/url]
was in his pinconfig, and why he might want it.
Think of a dead band in A-to-D conversion.
Fun, fun, fun!
[img width=500 height=422][/img]
battery unless you regularly monitor it with a voltmeter and
know when to take it off. Even a little 1 amp charger can
over-voltage and destroy your battery if you leave it on
long enough!
You need a "smart" or "constant voltage" (it isn't really, but)
charger which varies it's output current with the battery
voltage. Once the battery voltage gets high enough, it
drops it's charging current to avoid damaging the battery.
Here is what a "smart charger" voltage looks like:
[img width=500 height=333][/img]
Note that it charges up to 14.3 volts and then
shuts off. The battery slowly falls down and then
before sulfation can begin at 12.8V, it spanks
the battery again. Rinse, lather, repeat as the
shampoo bottle says.
There are many good brands of "smart" chargers,
such as CTEK, Genius and the original Battery
Tender, which I buy because they are simple and
cheap and do a great job of keeping a good battery
in good shape.
PS As I say to the kids at work, 30 years ago I
used to be an electrical engineer. Today, not
so much. I am amused, though, when people
mistake me for a hardware engineer. No, I write
software, but recently I had to explain to a young
fellow what
[url=https://en.wikipedia.org/wiki/Schmitt_trigger]https://en.wikipedia.org/wiki/Schmitt_trigger[/url]
was in his pinconfig, and why he might want it.
Think of a dead band in A-to-D conversion.
Fun, fun, fun!
[img width=500 height=422][/img]