On Thu, 17 Jun 2010 08:50:48 -0700, Kevin McMurtrie
wrote:
In article ,
default wrote:
On Thu, 17 Jun 2010 00:19:34 -0700, Kevin McMurtrie
wrote:
In article ,
default wrote:
On Wed, 9 Jun 2010 13:13:46 +0930, "mark krawczuk"
wrote:
hi, after some schematics to charge 6 volt and 12 volt sla ( sealed
lead
acid ) batteries.... basically dont need to charge them flat out , cause
they dont get used much, something i can leave on trickle charge for a
week
or so , would be good....
any body have any or know of any links ?
http://electronicdesign.com/article/...ry-charger-usi
ng-
a-single-trans.aspx
http://archive.electronicdesign.com/.../figure_01.gif
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Awesome circuit.
High battery drain: Check
Replace SRC with expensive relay: Check
Wildly unstable voltage sensing: Check
Capacitor to weld relay shut: Check
Wrong unit symbols: Check
OK, publish!
Why do you suppose it is easier to find fault with other people's
efforts than one's own? Lack of the adoration one feels entitled to?
Some childhood psychological need that wasn't met? Easy to bolster
one's ego by denigrating others? In an overpopulated world
competition supplants cooperation as a survival strategy?
Perhaps you could just address the problems you see in this simple
circuit and show how you would do it differently? Without, of course,
letting the complexity, cost or need for custom parts destroy the easy
to build with parts on hand aspects of it.
It has drawbacks if perfection is the goal, but all engineering is
compromise.
The cap discharge is easily remedied with a steering diode. Unstable
voltage sensing - more like it may need some temperature compensation
if repeatability is a goal - that's assuming that the design doesn't
happen to coincide with the battery's optimal charge/temperature
tracking. The biggest flaw is the lack of some current limiting in my
opinion. This circuit would self destruct if it tried to charge a
shorted battery.
Do you have anything positive to add?
--
Ooops. Meant to say "SCR" but it was late.
It's cool. I have one of the Heathkit lead acid chargers from years
ago. It died twice before I figured out lightening was killing it.
Ground the (floating) negative to the chassis seems to have fixed it
(10 years ago)
I think it's OK to criticize a circuit that's worse than what Google
search results provide.
Thing is, no one does any research for the beginning op. Sure he
should Google it first (and from the number of hits shouldn't ever
post a question) - in an ideal world.
The "basic group" should (to my way of thinking) answer and aid
beginners.
God knows a time or two my questions have been answered by no less
Walt Jung, Don Lancaster, and Bob Pease. Icons . . .
There has to be a free exchange of ideas (screw politics and ego). No
one has the insight you do - and you don't have the insight of others.
Carried to a logical conclusion . . .
The skid row bum, sitting in feces and vomit, will have a different
perspective than you or I. That doesn't mean we can't learn
Doesn't mean he isn't knowledgeable about his own world - he has more
knowledge than you or I, in that respect.
Learning is the active, teaching is the passive.
Critique the circuit, god knows it has flaws, but post the analysis
and corrections you would recommend, and why.
And here I sit - presuming to take on the mantle of wise peaceful
coexistence - when honest people liken my diplomatic skill to Attila
the Hun on steroids.
"Don't care who or how you **** someone off," That's their problem.
Worry about yourself.
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