ST head modification for 48 volt battery charging

[mbryner]

Hey bschwartz,

I'm really interested to see if this ST head mod works for you.   Tried to look at the photobucket pics but the links don't go anywhere.   (they try to go to ftp://http//s828.photobucket .... which is an invalid web address format.)

Marcus

Edit: maybe photobucket site is down, because I can't get to it at all.
Edit2: the photobucket site is back up.  You need to remove the ftp:// from the beginning of those picture links.

[mbryner]

Bob,

You mention that because 60 vac rectified is ~84 we would need some sort of voltage regulation for charging.   The good thing about a Listeroid is that we can easily just make it run slower to decrease the voltage.   The lower ripple frequency in the rectified DC shouldn't matter much, correct?

[bschwartz]

http://s828.photobucket.com/albums/zz204/brettschwartz/?action=view&current=jumpers.jpg
http://s828.photobucket.com/albums/zz204/brettschwartz/?action=view&current=stator.jpg

Try these, and let me know.

[bschwartz]

Ooohhhh, Ahhhhh....... Look what I can do if I read....

[bschwartz]

Anyone have any ideas where I go from here?

[mobile_bob]

next step would be to identify the coil pairs for each leg

so perhaps apply 12vdc to one 120volt leg and use a small wrench or something to see where the magnetizm
comes from,

like i said i would assume each leg is comprised of two groups of two coils displaced by 180 degree's, but
they may very well be placed 90 degree's apart

once you determine their spacing and placement, you will need to follow the lead down to the first coil, and identify
it, then follow the lead out from the other coil and identify it, then comes the work to find
the jumper interconnect between the two coils.

you might want to carefully open up one lead to see if it connects to a single wire at the stator, or if it connects
to two or three, which would indicate it is wound "two in hand" or "three in hand"

if it is a single wire, the jumper should also be a single wire, if it is two in hand the jumper will have two wires
and same for three in hand having three wires in the jumper.

whatever the case the jumper has to connect one coil to the other coil so it may be buried down in there or in relatively plain
sight, i suspect you should be able to find it quite easily with a little careful looking around.

i would be tempted to make thing easier, to get maybe 4 bottle of nail polish, use something like red for the Z winding, just put a dab
on them, along with their leads, maybe orange for the switch/lamp winding, blue for one coil pair to one 120volt leg, and maybe green
for the other,

this might make sorting out and keeping all the coil sets with their leads much easier to keep track of?

your pictures while good, don't show the kind of detail needed on my end to be of much more help, this is the sort of thing
where you will be rocking the stator core from side to side, up/down and all around trying to see in and track coil groups, jumpers
and various leads.

sorry to not be of more help, my eyes are just not that good looking through the puter screen

bob g

[bschwartz]

Bob,
I think you just gave me part of the info I needed.  I see two sets of three wires that appear to be the jumpers between coils.  I didn't realize that three wires was a possibility.  Now that I'm fairly confident that I've found the three wires "three in hand" as you say, where do I go from there.  One wire I know I'd just cut and splice in some extra leads to come out the top of the head with the others and work from there.  What do I do with the "three in hand" situation?

[potter]

Check and make sure that you have three wires tied at the starts and finishes of the coils first to be sure they are wound three in hand.If so then the three wires are treated as if they were one single wire and simply cut and leads attached.

  Potter

[bschwartz]

I reread your post a few times before it hit me in the head what "three in hand" meant.  Three parallel wires wound together to carry more current than one wire of the same gauge could handle.  YES!!!! That is the answer!!  In the second picture my finger is pointing to the TIH jumper from one coil to the next.  Bob, you are a genius!  Now I just have to cut, solder and attach a long lead to come out to the doghouse with the others.  I will try to take better pictures so others that want to do this understand.

[mobile_bob]

be sure to use some high temp rated wire for your leads, and you might want
to get some form of crimp connector to crimp and solder to make a good tight connection

also some insulating sleaving would finish it off nicely.

also make sure to lace in the splice area's tightly, you don't want vibration to work the connection
if you can keep from it.

btw, i have a large frame leece neville very high output alternator that is wound 4 in hand, and several wound
3 in hand, its a good way to increase the ampacity of the coil without adding issues with eddy currents in heavy section
single conductor construction.

bob g

btw, i am no genius, just a determined old fart



when you get this conversion done, you will have the first one that i am aware of
so you are breaking ground here, and i am sure there will be many to follow the
"bschwartz" ST modification

[bschwartz]

Bob,
As my name is Brett Schwartz, I think this will be called the "BS ST modification" That way, BS can stand for what ever people want.

[bschwartz]

OK, progress so far:
ST apart
wiring identified and labeled
"jumpers" identified between coils located not 180 degrees apart, but 270 degrees apart (ya, I know but 90 degrees seems boring)
"jumpers" cut, varnish removed and tinned with solder
"jumpers" checked for continuity with other ends and labeled as X1, X2, X5, X6 to match up with the other ends U1, U2, U5, U6.
I'm going away to visit family and will return on the 31st.  I still need heat shrink tubing and butt connectors, so I guess I'm stuck for now.

U2 three in hand jumper before and after cutting, tinning, and labeling.

Before I go any further, let me know if you want any more pictures.

[mobile_bob]

270 degree's huh?  funny guy you are! 

you might be able to make a small crimp out of a short piece of copper tubing
crimp and sweat solder the connection, shrink tube it, sleeve and lace it back in

and you should be good to go.

the nice thing about the modification is, you can still make the external interconnects
and get the original operation restored.

looks like your almost there

bob g

[bschwartz]

Sweat soldering and shrink tubing I get... What should I sleeve it with?  I ran the new leads through the original doghouse sleeves.  Do I need to sleeve even further?  What purpose does it serve?
Thanks for all your help.

[mobile_bob]

sleeveing is a tough abrasion resistant stuff, some made of kevlar, some other fibers
they protect from shorts to other wires and grounds, over time.

if you can't get what you need let me know, i have some kevlar sleeve in various sizes, i suppose i could send you
enough to secure this project

just let me know about what ID you need, and how long will you need to do all the extra leads

bob g