Adding a 6v boost to a 12v battery charger...

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Adding a 6v boost to a 12v battery charger...

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Too_Many_Tools...

Posted: Mon Nov 02, 2009 10:25 am

Guest

I have access to a Schumacher wheeled battery charger that is 12 v
only.

I want to use its boost feature (200amp) on 6 volt systems.

Any suggestions as to how to make a mod where the charger will do both
12v and 6v?

I have looked and have not found any schematics.

I am assuming that any mods will be downstream of the transformer.

Thanks for any suggestions.

TMT

whit3rd...

Posted: Mon Nov 02, 2009 11:01 am

Guest

On Nov 2, 12:25 pm, Too_Many_Tools <too_many_to... at (no spam) yahoo.com> wrote:
[quote]I have access to a Schumacher wheeled battery charger that is 12 v
only.

I want to use its boost feature (200amp) on 6 volt systems.

Any suggestions as to how to make a mod where the charger will do both
12v and 6v?
[/quote]
That's a kilowatt problem, of course...
If the charger has inductive filtering on the outputs (this is
likely, because it allows better rectifier conduction
duty cycle, keeps things cheaper), then you might be able to
lower the RMS input voltage from 120VAC to something
lower, and get proportional output. Some kinds of
light dimmer (the ones for inductive loads, like dimmed
halogen-lights-on-a-transformer) can safely handle it.

amdx...

Posted: Mon Nov 02, 2009 4:07 pm

Guest

"Too_Many_Tools" <too_many_tools at (no spam) yahoo.com> wrote in message
news:62f9120d-61aa-430d-bdaa-dfcb1077d484 at (no spam) v36g2000yqv.googlegroups.com...
[quote]I have access to a Schumacher wheeled battery charger that is 12 v
only.

I want to use its boost feature (200amp) on 6 volt systems.

Any suggestions as to how to make a mod where the charger will do both
12v and 6v?

I have looked and have not found any schematics.

I am assuming that any mods will be downstream of the transformer.

I think that's not a good assumption.[/quote]
You need about a 6 volt tap on the transformer.
I had an old battery charger/car starter that put out 300 amps at 10.5
volts.
Somebody stole it, %$&^%!
Mike

[quote]Thanks for any suggestions.

TMT[/quote]

Too_Many_Tools...

Posted: Tue Nov 03, 2009 8:44 am

Guest

On Nov 2, 2:25 pm, Too_Many_Tools <too_many_to... at (no spam) yahoo.com> wrote:
[quote]I have access to a Schumacher wheeled battery charger that is 12 v
only.

I want to use its boost feature (200amp) on 6 volt systems.

Any suggestions as to how to make a mod where the charger will do both
12v and 6v?

I have looked and have not found any schematics.

I am assuming that any mods will be downstream of the transformer.

Thanks for any suggestions.

TMT
[/quote]
Thanks for the responses so far...anyone else?

And any suggestions to other sites where I can post this question?
Links please.

Thanks

Too_Many_Tools...

Posted: Wed Nov 04, 2009 9:39 am

Guest

On Nov 3, 12:44 pm, Too_Many_Tools <too_many_to... at (no spam) yahoo.com> wrote:
[quote]On Nov 2, 2:25 pm, Too_Many_Tools <too_many_to... at (no spam) yahoo.com> wrote:

I have access to a Schumacher wheeled battery charger that is 12 v
only.

I want to use its boost feature (200amp) on 6 volt systems.

Any suggestions as to how to make a mod where the charger will do both
12v and 6v?

I have looked and have not found any schematics.

I am assuming that any mods will be downstream of the transformer.

Thanks for any suggestions.

TMT

Thanks for the responses so far...anyone else?

And any suggestions to other sites where I can post this question?
Links please.

Thanks
[/quote]
No more suggestions?

Any suggestions where I could post this question where designers hang
out?

Thanks

TMT

Too_Many_Tools...

Posted: Wed Nov 04, 2009 9:51 am

Guest

On Nov 2, 2:25 pm, Too_Many_Tools <too_many_to... at (no spam) yahoo.com> wrote:
[quote]I have access to a Schumacher wheeled battery charger that is 12 v
only.

I want to use its boost feature (200amp) on 6 volt systems.

Any suggestions as to how to make a mod where the charger will do both
12v and 6v?

I have looked and have not found any schematics.

I am assuming that any mods will be downstream of the transformer.

Thanks for any suggestions.

TMT
[/quote]
Let's try casting the net a bit further...anyone else have a
suggestion as to how to do a conversion?
Thanks

TMT

Baron...

Posted: Wed Nov 04, 2009 3:31 pm

Guest

Too_Many_Tools wrote:

[quote]On Nov 2, 2:25Â pm, Too_Many_Tools <too_many_to... at (no spam) yahoo.com> wrote:
I have access to a Schumacher wheeled battery charger that is 12 v
only.

I want to use its boost feature (200amp) on 6 volt systems.

Any suggestions as to how to make a mod where the charger will do
both 12v and 6v?

I have looked and have not found any schematics.

I am assuming that any mods will be downstream of the transformer.

Thanks for any suggestions.

TMT

Let's try casting the net a bit further...anyone else have a
suggestion as to how to do a conversion?
Thanks

TMT
[/quote]
Why don't you open it up and see if its got any taps on the output of
the transformer. Or if you are lucky a 220/230 volt centre tapped
primary winding.

--
Best Regards:
Baron.

Too_Many_Tools...

Posted: Wed Nov 04, 2009 3:37 pm

Guest

On Nov 4, 3:48 pm, John Fields <jfie... at (no spam) austininstruments.com> wrote:
[quote]On Wed, 4 Nov 2009 11:39:46 -0800 (PST), Too_Many_Tools

too_many_to... at (no spam) yahoo.com> wrote:
On Nov 3, 12:44 pm, Too_Many_Tools <too_many_to... at (no spam) yahoo.com> wrote:
On Nov 2, 2:25 pm, Too_Many_Tools <too_many_to... at (no spam) yahoo.com> wrote:

I have access to a Schumacher wheeled battery charger that is 12 v
only.

I want to use its boost feature (200amp) on 6 volt systems.

Any suggestions as to how to make a mod where the charger will do both
12v and 6v?

I have looked and have not found any schematics.

I am assuming that any mods will be downstream of the transformer.

Thanks for any suggestions.

TMT

Thanks for the responses so far...anyone else?

And any suggestions to other sites where I can post this question?
Links please.

Thanks

No more suggestions?

Any suggestions where I could post this question where designers hang
out?

---
Plenty of good designers hang out here, but you're not going to get
anywhere being a smartass.

If I were you, I'd get ahold of someone at Schumacher,

http://www.schumacherproducts.com/contact

tell them what you want to do, and see if they can't come up with a
solution for you. Or, at the very least, a schematic.

If they can't help you with anything more than a schematic and you can
post it, then do that and maybe someone from around here will help you
out.

If you can't get a schematic, you can always "reverse engineer" the
thing, post what you find, and skin the cat that way.

JF- Hide quoted text -

- Show quoted text -
[/quote]
I am not trying to be a smartass.

My apologies to anyone who thought I was.

When a question is out there for days with minimal responses, you
prompt the group for any other comments before moving on..which I did.

TMT
TMT

John Fields...

Posted: Wed Nov 04, 2009 4:48 pm

Guest

On Wed, 4 Nov 2009 11:39:46 -0800 (PST), Too_Many_Tools
<too_many_tools at (no spam) yahoo.com> wrote:

[quote]On Nov 3, 12:44 pm, Too_Many_Tools <too_many_to... at (no spam) yahoo.com> wrote:
On Nov 2, 2:25 pm, Too_Many_Tools <too_many_to... at (no spam) yahoo.com> wrote:

I have access to a Schumacher wheeled battery charger that is 12 v
only.

I want to use its boost feature (200amp) on 6 volt systems.

Any suggestions as to how to make a mod where the charger will do both
12v and 6v?

I have looked and have not found any schematics.

I am assuming that any mods will be downstream of the transformer.

Thanks for any suggestions.

TMT

Thanks for the responses so far...anyone else?

And any suggestions to other sites where I can post this question?
Links please.

Thanks

No more suggestions?

Any suggestions where I could post this question where designers hang
out?
[/quote]
---
Plenty of good designers hang out here, but you're not going to get
anywhere being a smartass.

If I were you, I'd get ahold of someone at Schumacher,

http://www.schumacherproducts.com/contact

tell them what you want to do, and see if they can't come up with a
solution for you. Or, at the very least, a schematic.

If they can't help you with anything more than a schematic and you can
post it, then do that and maybe someone from around here will help you
out.

If you can't get a schematic, you can always "reverse engineer" the
thing, post what you find, and skin the cat that way.

JF

George Herold...

Posted: Wed Nov 04, 2009 5:35 pm

Guest

On Nov 4, 5:44 pm, John Fields <jfie... at (no spam) austininstruments.com> wrote:
[quote]On Wed, 4 Nov 2009 11:51:47 -0800 (PST), Too_Many_Tools

too_many_to... at (no spam) yahoo.com> wrote:
On Nov 2, 2:25 pm, Too_Many_Tools <too_many_to... at (no spam) yahoo.com> wrote:
I have access to a Schumacher wheeled battery charger that is 12 v
only.

I want to use its boost feature (200amp) on 6 volt systems.

Any suggestions as to how to make a mod where the charger will do both
12v and 6v?

I have looked and have not found any schematics.

I am assuming that any mods will be downstream of the transformer.

Thanks for any suggestions.

TMT

Let's try casting the net a bit further...anyone else have a
suggestion as to how to do a conversion?

---
Since the boost function is only used to try to start an engine, then
figure if you want to cut the 12V down to 6 and you want to be drawing
200 amps at that time, then you might be able to just insert a 30
milliohm 1200 watt resistor between the battery and the charger.

There are power resistors available from various vendors which you could
use:

http://www.ohmite.com/cgi-bin/showpage.cgi?product=powrrib_series#parts

or you could make your own out of nichrome wire.

JF- Hide quoted text -

- Show quoted text -
[/quote]
OK, I kinda hate to suggest this as a solution... I'm afraid too-many-
tools will become too-few....

But, if you had a second UNCHARGED battery to put in series it could
act as the dropping resistor.

Please note the emphasis on uncharged. I'm afraid you will blow
something up!

George H.

John Fields...

Posted: Wed Nov 04, 2009 5:44 pm

Guest

On Wed, 4 Nov 2009 11:51:47 -0800 (PST), Too_Many_Tools
<too_many_tools at (no spam) yahoo.com> wrote:

[quote]On Nov 2, 2:25 pm, Too_Many_Tools <too_many_to... at (no spam) yahoo.com> wrote:
I have access to a Schumacher wheeled battery charger that is 12 v
only.

I want to use its boost feature (200amp) on 6 volt systems.

Any suggestions as to how to make a mod where the charger will do both
12v and 6v?

I have looked and have not found any schematics.

I am assuming that any mods will be downstream of the transformer.

Thanks for any suggestions.

TMT

Let's try casting the net a bit further...anyone else have a
suggestion as to how to do a conversion?
[/quote]
---
Since the boost function is only used to try to start an engine, then
figure if you want to cut the 12V down to 6 and you want to be drawing
200 amps at that time, then you might be able to just insert a 30
milliohm 1200 watt resistor between the battery and the charger.

There are power resistors available from various vendors which you could
use:

http://www.ohmite.com/cgi-bin/showpage.cgi?product=powrrib_series#parts

or you could make your own out of nichrome wire.

JF

PeterD...

Posted: Wed Nov 04, 2009 7:27 pm

Guest

Jamie...

Posted: Wed Nov 04, 2009 8:30 pm

Guest

Too_Many_Tools wrote:

[quote]On Nov 3, 12:44 pm, Too_Many_Tools <too_many_to... at (no spam) yahoo.com> wrote:

On Nov 2, 2:25 pm, Too_Many_Tools <too_many_to... at (no spam) yahoo.com> wrote:

I have access to a Schumacher wheeled battery charger that is 12 v
only.

I want to use its boost feature (200amp) on 6 volt systems.

Any suggestions as to how to make a mod where the charger will do both
12v and 6v?

I have looked and have not found any schematics.

I am assuming that any mods will be downstream of the transformer.

Thanks for any suggestions.

TMT

Thanks for the responses so far...anyone else?

And any suggestions to other sites where I can post this question?
Links please.

Thanks

No more suggestions?

Any suggestions where I could post this question where designers hang
out?

Thanks

TMT
It should be obvious by now, that to many want to step up to[/quote]
the plate.

There are ways, but if you can't comprehend the basics of how,
would it make any difference?

And I thought this was answered once before ? Or are you just
spamming?

For starters, assuming that this unit has no voltage reliant devices
in it. install a step down 2kw transformer to drop the incoming by
half.

The price of this xformer will most doubtably change your mind on the
project.

Joe Rooney...

Posted: Thu Nov 05, 2009 2:19 am

Guest

"John Fields" <jfields at (no spam) austininstruments.com> wrote in message
news:2ut3f5lttj9qvtjga9hqmohlftj6dfo51g at (no spam) 4ax.com...
[quote]On Wed, 4 Nov 2009 11:51:47 -0800 (PST), Too_Many_Tools
too_many_tools at (no spam) yahoo.com> wrote:
[/quote]
snip

I presume this is one of those wheel around big guys seen at repair shops
and service stations.

I take it that the 200 amp is a feature you can select to start vehicles if
you are in a big hurry and can't wait for the original battery to accept an
adequate charge.

The 6 volt battery will, for a time, swamp the 14-16 volt charging voltage
output down to the 7 or 8 volts if you hook it up as is. Better if you have
a trickle charge or lower charging current feature selection to buy yourself
more time with the 12 volt charging hook up.

You could then actuate the 200 amp feature to see if you can start the
problematic vehicle. But I wouldn't leave it on for long.

Older chargers used selenium rectifier stacks and they have a built in
current limiting (intrinsic resistance) and are very conservatively built.

Charging batteries is hazardous even with the right equipment, but unless
this is a very tiny ampere hour battery, you should be able to do it for a
minute or two before you start heating up the plates and permanently
destroying the battery and possibly the rest of the automotive electrical
system.

The suggestion about adding another 6 volt battery in series would work as
well, you would have to position it between the vehicle being charged and
hook up the positive of the vehicle battery to the negative pole of this
added battery. The positive of the added battery going to the potitive lead
of the charger.

Joe Rooney

Too_Many_Tools...

Posted: Fri Nov 06, 2009 8:22 am

Guest

On Nov 4, 1:51 pm, Too_Many_Tools <too_many_to... at (no spam) yahoo.com> wrote:
[quote]On Nov 2, 2:25 pm, Too_Many_Tools <too_many_to... at (no spam) yahoo.com> wrote:

I have access to a Schumacher wheeled battery charger that is 12 v
only.

I want to use its boost feature (200amp) on 6 volt systems.

Any suggestions as to how to make a mod where the charger will do both
12v and 6v?

I have looked and have not found any schematics.

I am assuming that any mods will be downstream of the transformer.

Thanks for any suggestions.

TMT

Let's try casting the net a bit further...anyone else have a
suggestion as to how to do a conversion?
Thanks

TMT
[/quote]
Okay...I found a schematic of a similar charger that Sears sells....

http://www.searspartsdirect.com/partsdirect/getSubComp.pd?modelNumber=200..71230&productCategoryId=0405000&brandId=3206&modelName=BATTERY-CHARGER&diagramPageId=00001&documentId=P0305118&pop=flush

Does this help?

TMT

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