12V 60A car battery , maybe dead?

[Groundloop]

Topper,

If you use two strands of your 0,6mm enameled copper wire in parallel
for each of you three coils, then you will have thick enough wire in total.
I do not remember the dc resistance of the coils now, sorry, but if you
use approx. the same number of turns as posted in the circuit drawing
then the circuit will perform fine. It is not a critical design at all.

GL. 

[topper]

Hi,

Ok i understand trifilar coil with 3 wires that every has two strands of 0.6mm give us 6 filar coil and lot of work:). Two strands for carry the bigger current.
But bigger current wont cause the coil or transistor very hot? I thought to use only tree wires of 0.6 mm not doubled for lower heating. Will it work with that circuit?

And this circuit i cannot control how fast and how big current the battery is charged. Lets say i want to charge smaller batteries than 60 Ah ( 7 ah, 18 ah). Could be worth of putting instead of "R2" -500 ohm 4 watt potentiometer?

Any help is very appreciated:)

Topper

[Groundloop]

Topper,

Use a heat sink on the transistor. You can increase the value of the potmeter
to 1k to get a lower output from the circuit. You can use 0,6mm wire if you want
but there is a probablibility for wire heating at higher power. (Thin wire will heat more
than thick wire if you send high current through them.)

GL.

[CompuTutor]

The BUX80 is hard to find these days...

There still arround though,
I just got four off of eBay for $5,
$10 for all four delivered actually.

They are out there as NOS (New Old-Stock),
mine were from a retired repairmen as example,
they are even the good (RE: original) Philips ones.



EDIT:
I have written Fuji Semiconductor about another part.

You can find them on eBay as this:
"300V 20A Super High Speed Rectifier"

They come as a common cathode diode pair
in a handy TO3-P sinkable casing style.

Their simple name is roughly D92-02, D92-03, Etc.,
but they come with up to four letter prefix's,
and a few letter's worth of special part suffix's too.

I have written them asking for the part numbers for
the complimentary-opposite common-anode version
that would allow simple (two part) FWBR's for us.

These are slick,
and catch more of a coil collapse spike than many...



Your's are a good pick too (BYV29-500),
and only $1.37 each at Newark as example:
http://www.newark.com/jsp/search/productdetail.jsp?SKU=70R3667&CMP=AFC-GB100000001
But they are mid 60's in nanosecond recovery, pretty good,
but the D92-xx series is mid 30's of nanosecond recovery.

They are also the same buck-and-ahalf (US) or so in price...

Every bit helps.

Hope this helps.

[CompuTutor]

Attached is a image of my unit.
As you can see I use two transistors in parallel
so that I do not need a very big heat sink.

Um,
how the heck did you squeeze a 12 centimeter coil in that box, heheh ?