rocketeer wrote:
>> I was thinking of a higher voltage turn on and a quicker rise in
>> current.
Steve Clunn wrote:
> This is what I thought at first, with 6.8 and 6.2 v zeners that adds
> to 13v... the light bulb does not let much current flow till the
> voltage gets over a volt or so.
Yes; but at 13v that leaves 0v for the lamp, so the current is zero.
Since a fully charged battery is about 13v, this means the zener-lamp
regulator won't draw current from a fully charged battery.
> so I got 2 6.8 giving 13.6v but when I hooked it up it almost seemed
> like the turn on threshold was a bit hi
Yes, this is a better combination for flooded batteries, where you want
to let them get to a higher voltage and gas a bit.
> As was said before you need to have the
> current turned down on your charger if your batteries are out of
> balance when you get to the end of your first charge as you will
> burn out the bulbs if the voltage goes over 17v. I've been thinking
> about replacing the bulb with a 5w 4 to 6 ohm resistor as the bulbs
> are hard to solder to and the zeners seem to work fine as fuses
I had the opposite experience; the zeners tend to fail *shorted* if
overloaded or overheated. Then the lamp burns out, acting as a fuse.
If you replace the lamp with a resistor, I'd be concerned that a zener
failure will make the resistor get extremely hot, melting something or
perhaps even starting a fire. Even if the resistor doesn't fail, it will
run your battery dead.
> light the light that saves a bat
> help that sunrise imagine that
> just a million points of light
> an electric kit car done just right
> the simplest ideas happily gives fruit.
Very good! Thanks, Steve!
> PS Here's an Idea ,,, lets get some EV parts supplier to sell all
> the parts to make your LBR ( light bulb reg's) and add 1 dollar to
> there sale price , then send you the dollar per reg when they sell .
> Could even tell what the dollar was going for, sunrise project ,
> then you don't have to do anything but cash the checks. Parts
> supplier could get large quantity's and maybe sell for less than what
> a small quantity would cost. Maybe EV supplier could have your stamp
> of approval.
I make these regs up on occasion as needed. The parts are cheap, but
they're labor intensive (if you build them right). But if people want
them as kits, I'd be glad to "bag 'em up" and sell them with instructions.
Or, the "cat's out of the bag", so anyone can do this. To be honest, the
same sort of person that is attracted to these regs also tends to cheap
out on the parts. Some of the examples I've seen on the web are pretty
cheesy. They'll use small ring terminals, skip the heat conductive
potting, not bother to insulate the wiring, etc. They'll still work for
a while; but I wonder what they'll look like in a year or two?
--
Lee A. Hart | Ring the bells that still can ring
814 8th Ave N | Forget the perfect offering
Sartell MN 56377 | There is a crack in everything
leeahart earthlink.net | That's how the light gets in -- Leonard Cohen
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