elektroda.net NewsGroups Forum Index - Electronics Design - Project Float Charger
RogerN
Guest
Guest
Tue Feb 23, 2010 4:16 am
I'm interested in doing a project both for the practice and to be useful.
It would be something like a Battery Tender automatic float charger.
The basic idea is a microcontroller to control based on battery voltage and
current. If I understand correctly, you charge at maximum current until you
reach 14.4V on a 12V battery, then you lower the current to prevent the
voltage from going over 14.4V. After the current reduces to perhaps 0.1A,
the charge is terminated and float mode keeps the voltage at 13.2V, if the
voltage goes under 12.6V, the charge cycle is restarted.
My question is what to use to interface the microcontroller to the battery?
Voltage regulator circuit or what. I need to sense voltage and current and
control the output. I can come up with something to work but I'm looking
for ideas that might be better than mine.
RogerN
ehsjr
Guest
Guest
Tue Feb 23, 2010 7:09 am
RogerN wrote:
Quote:
I'm interested in doing a project both for the practice and to be useful.
It would be something like a Battery Tender automatic float charger.
It would be something like a Battery Tender automatic float charger.
What you describe below is not a float charger, so you should
change the subject line to battery charger.
Quote:
The basic idea is a microcontroller to control based on battery voltage and
current. If I understand correctly, you charge at maximum current until you
reach 14.4V on a 12V battery, then you lower the current to prevent the
voltage from going over 14.4V.
Do some more research on battery charging. You don't charge at
maximum current, you limit the maximum current.
Quote:
After the current reduces to perhaps 0.1A,
If you're talking about a lead acid type battery, you
charge it to ~14.4 volts, then derop the charging voltage.
In any event, the .1A figure is meaningless without
knowing the battery capacity as well as type.
Quote:
the charge is terminated and float mode keeps the voltage at 13.2V,
(Again, lead acid assumed) 13.4 or 13.5 is a better target. 13.2 is
a bit too low.
Quote:
if the
voltage goes under 12.6V, the charge cycle is restarted.
voltage goes under 12.6V, the charge cycle is restarted.
That ("charge cycle") means you are not float charging the battery.
Quote:
My question is what to use to interface the microcontroller to the battery?
Voltage regulator circuit or what. I need to sense voltage and current and
control the output. I can come up with something to work but I'm looking
for ideas that might be better than mine.
You really need to specify a proper charging scheme before
worrying about a ucontroller.
Ed
Quote:
RogerN
Jan Panteltje
Guest
Guest
Tue Feb 23, 2010 12:53 pm
On a sunny day (Mon, 22 Feb 2010 21:16:20 -0600) it happened "RogerN"
<regor_at_midwest.net> wrote in <D-ednWKLu70R1R7WnZ2dnUVZ_gWdnZ2d_at_earthlink.com>:
Quote:
I'm interested in doing a project both for the practice and to be useful.
It would be something like a Battery Tender automatic float charger.
The basic idea is a microcontroller to control based on battery voltage and
current. If I understand correctly, you charge at maximum current until you
reach 14.4V on a 12V battery, then you lower the current to prevent the
voltage from going over 14.4V. After the current reduces to perhaps 0.1A,
the charge is terminated and float mode keeps the voltage at 13.2V, if the
voltage goes under 12.6V, the charge cycle is restarted.
My question is what to use to interface the microcontroller to the battery?
Voltage regulator circuit or what. I need to sense voltage and current and
control the output. I can come up with something to work but I'm looking
for ideas that might be better than mine.
RogerN
It would be something like a Battery Tender automatic float charger.
The basic idea is a microcontroller to control based on battery voltage and
current. If I understand correctly, you charge at maximum current until you
reach 14.4V on a 12V battery, then you lower the current to prevent the
voltage from going over 14.4V. After the current reduces to perhaps 0.1A,
the charge is terminated and float mode keeps the voltage at 13.2V, if the
voltage goes under 12.6V, the charge cycle is restarted.
My question is what to use to interface the microcontroller to the battery?
Voltage regulator circuit or what. I need to sense voltage and current and
control the output. I can come up with something to work but I'm looking
for ideas that might be better than mine.
RogerN
http://panteltje.com/panteltje/pic/pwr_pic/index.html
RogerN
Guest
Guest
Tue Feb 23, 2010 12:57 pm
"ehsjr" <ehsjr_at_nospamverizon.net> wrote in message
news:hlvrel$djo$1_at_news.eternal-september.org...
Quote:
RogerN wrote:
I'm interested in doing a project both for the practice and to be useful.
It would be something like a Battery Tender automatic float charger.
What you describe below is not a float charger, so you should
change the subject line to battery charger.
I'm interested in doing a project both for the practice and to be useful.
It would be something like a Battery Tender automatic float charger.
What you describe below is not a float charger, so you should
change the subject line to battery charger.
I got the information from Maxim IC and Battery Tender websites.
Quote:
The basic idea is a microcontroller to control based on battery voltage
and current. If I understand correctly, you charge at maximum current
until you reach 14.4V on a 12V battery, then you lower the current to
prevent the voltage from going over 14.4V.
Do some more research on battery charging. You don't charge at
maximum current, you limit the maximum current.
and current. If I understand correctly, you charge at maximum current
until you reach 14.4V on a 12V battery, then you lower the current to
prevent the voltage from going over 14.4V.
Do some more research on battery charging. You don't charge at
maximum current, you limit the maximum current.
I meant the maximum rated current for my battery charging circuit, I will
probably have a 1.5A charger so my maximum current will be 1.5A. I guess I
would prefer to call the stages current limited, voltage limited, and float.
Quote:
After the current reduces to perhaps 0.1A,
If you're talking about a lead acid type battery, you
charge it to ~14.4 volts, then derop the charging voltage.
In any event, the .1A figure is meaningless without
knowing the battery capacity as well as type.
If you're talking about a lead acid type battery, you
charge it to ~14.4 volts, then derop the charging voltage.
In any event, the .1A figure is meaningless without
knowing the battery capacity as well as type.
My info was from Maxim IC and/or Battery Tender website. I thought possible
loads on the battery could als prevent the current from ever going to the
full charge state.
Quote:
the charge is terminated and float mode keeps the voltage at 13.2V,
(Again, lead acid assumed) 13.4 or 13.5 is a better target. 13.2 is
a bit too low.
(Again, lead acid assumed) 13.4 or 13.5 is a better target. 13.2 is
a bit too low.
That is a minor software adjustment, I also plan to sense temperature and
adjust the voltages accordingly.
Quote:
if the voltage goes under 12.6V, the charge cycle is restarted.
That ("charge cycle") means you are not float charging the battery.
My question is what to use to interface the microcontroller to the
battery? Voltage regulator circuit or what. I need to sense voltage and
current and control the output. I can come up with something to work but
I'm looking for ideas that might be better than mine.
You really need to specify a proper charging scheme before
worrying about a ucontroller.
Ed
That ("charge cycle") means you are not float charging the battery.
My question is what to use to interface the microcontroller to the
battery? Voltage regulator circuit or what. I need to sense voltage and
current and control the output. I can come up with something to work but
I'm looking for ideas that might be better than mine.
You really need to specify a proper charging scheme before
worrying about a ucontroller.
Ed
This is a microcontroller project, once the hardware is in place I can make
software changes to get the charging scheme right.
RogerN
MooseFET
Guest
Guest
Tue Feb 23, 2010 4:39 pm
On Feb 22, 7:16 pm, "RogerN" <re...@midwest.net> wrote:
Quote:
I'm interested in doing a project both for the practice and to be useful.
It would be something like a Battery Tender automatic float charger.
The basic idea is a microcontroller to control based on battery voltage and
current. If I understand correctly, you charge at maximum current until you
reach 14.4V on a 12V battery, then you lower the current to prevent the
voltage from going over 14.4V. After the current reduces to perhaps 0.1A,
the charge is terminated and float mode keeps the voltage at 13.2V, if the
voltage goes under 12.6V, the charge cycle is restarted.
My question is what to use to interface the microcontroller to the battery?
Voltage regulator circuit or what. I need to sense voltage and current and
control the output. I can come up with something to work but I'm looking
for ideas that might be better than mine.
It would be something like a Battery Tender automatic float charger.
The basic idea is a microcontroller to control based on battery voltage and
current. If I understand correctly, you charge at maximum current until you
reach 14.4V on a 12V battery, then you lower the current to prevent the
voltage from going over 14.4V. After the current reduces to perhaps 0.1A,
the charge is terminated and float mode keeps the voltage at 13.2V, if the
voltage goes under 12.6V, the charge cycle is restarted.
My question is what to use to interface the microcontroller to the battery?
Voltage regulator circuit or what. I need to sense voltage and current and
control the output. I can come up with something to work but I'm looking
for ideas that might be better than mine.
You don't really need the micro but if you really want to use one
then:
A PWM output to control the switching transistor in a buck topology
regulator
is likely already in the micro. You want this buck circuit to work
correctly
all the way down to zero volts on the output terminals. This means
you need
more inductance than you would for the normal case.
You need to be sensing the current going into the battery. A simple
resistor will do for this but the circuit must work with the output
shorted
to ground. You want this sensed current to provide instant feedback
that
shortens the on time when the limit is hit. You also want the micro
to
be able to see this current value on a ADC.
The terminal voltage of the battery needs to be measured by an ADC.
This
needs to be very accurate up at the full charge voltage. It doesn't
need
much accuracy at low voltages.
Measuring the temperature of the air or better yet the battery can
help
you to get the right charging voltage when the temperature is unusual.
Ideally you will have a MOSFET between the charger and the battery
that
isolates the battery from the charger when the power is off. You
don't
want the battery to be discharged if there is a power failure or your
system gets unplugged.
MooseFET
Guest
Guest
Tue Feb 23, 2010 4:44 pm
On Feb 23, 3:53 am, Jan Panteltje <pNaonStpealm...@yahoo.com> wrote:
Quote:
On a sunny day (Mon, 22 Feb 2010 21:16:20 -0600) it happened "RogerN"
re...@midwest.net> wrote in <D-ednWKLu70R1R7WnZ2dnUVZ_gWdn...@earthlink.com>:
I'm interested in doing a project both for the practice and to be useful..
It would be something like a Battery Tender automatic float charger.
The basic idea is a microcontroller to control based on battery voltage and
current. If I understand correctly, you charge at maximum current until you
reach 14.4V on a 12V battery, then you lower the current to prevent the
voltage from going over 14.4V. After the current reduces to perhaps 0..1A,
the charge is terminated and float mode keeps the voltage at 13.2V, if the
voltage goes under 12.6V, the charge cycle is restarted.
My question is what to use to interface the microcontroller to the battery?
Voltage regulator circuit or what. I need to sense voltage and current and
control the output. I can come up with something to work but I'm looking
for ideas that might be better than mine.
RogerN
http://panteltje.com/panteltje/pic/pwr_pic/index.html
re...@midwest.net> wrote in <D-ednWKLu70R1R7WnZ2dnUVZ_gWdn...@earthlink.com>:
I'm interested in doing a project both for the practice and to be useful..
It would be something like a Battery Tender automatic float charger.
The basic idea is a microcontroller to control based on battery voltage and
current. If I understand correctly, you charge at maximum current until you
reach 14.4V on a 12V battery, then you lower the current to prevent the
voltage from going over 14.4V. After the current reduces to perhaps 0..1A,
the charge is terminated and float mode keeps the voltage at 13.2V, if the
voltage goes under 12.6V, the charge cycle is restarted.
My question is what to use to interface the microcontroller to the battery?
Voltage regulator circuit or what. I need to sense voltage and current and
control the output. I can come up with something to work but I'm looking
for ideas that might be better than mine.
RogerN
http://panteltje.com/panteltje/pic/pwr_pic/index.html
Beware! When you design a battery charger, someone will always
connect the
battery backwards.
Tim Wescott
Guest
Guest
Tue Feb 23, 2010 6:18 pm
RogerN wrote:
Quote:
I'm interested in doing a project both for the practice and to be useful.
It would be something like a Battery Tender automatic float charger.
The basic idea is a microcontroller to control based on battery voltage and
current. If I understand correctly, you charge at maximum current until you
reach 14.4V on a 12V battery, then you lower the current to prevent the
voltage from going over 14.4V.
It would be something like a Battery Tender automatic float charger.
The basic idea is a microcontroller to control based on battery voltage and
current. If I understand correctly, you charge at maximum current until you
reach 14.4V on a 12V battery, then you lower the current to prevent the
voltage from going over 14.4V.
That's oddly stated. Normally a lead-acid battery charge is described
as "constant voltage with current limiting", and for all but absurdly
large chargers the current limiting is there for the charger, not he
battery. The _behavior_ is the same, but the normal description
captures the fact that the _important_ part is the constant voltage.
Note, too that the optimal charge voltage varies by battery temperature.
I don't know how critical this is, but my understanding is that if
you're going to be charging in an unheated space you want to monitor at
least ambient temperature and adjust the charge voltage accordingly.
Quote:
After the current reduces to perhaps 0.1A,
As mentioned, this magic current depends on the battery capacity to a
great extent, and (probably) to a lesser extent on the battery construction.
Quote:
the charge is terminated and float mode keeps the voltage at 13.2V, if the
voltage goes under 12.6V, the charge cycle is restarted.
My question is what to use to interface the microcontroller to the battery?
Voltage regulator circuit or what. I need to sense voltage and current and
control the output. I can come up with something to work but I'm looking
for ideas that might be better than mine.
That depends on how much work you want to load onto the microcontroller.
voltage goes under 12.6V, the charge cycle is restarted.
My question is what to use to interface the microcontroller to the battery?
Voltage regulator circuit or what. I need to sense voltage and current and
control the output. I can come up with something to work but I'm looking
for ideas that might be better than mine.
That depends on how much work you want to load onto the microcontroller.
You could just have a current-limited voltage amplifier (i.e. a
microprocessor-controlled regulator) that you set and forget, or you
could drive the base (or gate) of a transistor directly from a pin on
the micro and let the micro do _all_ the work, or you could go somewhere
in between. It depends on your abilities, and what you're trying to do.
There's are books on the care and feeding of batteries -- you may want
to get one. When I get downstairs I'll try to remember to send you info
on the one I have.
--
Tim Wescott
Control system and signal processing consulting
www.wescottdesign.com
Jan Panteltje
Guest
Guest
Tue Feb 23, 2010 9:42 pm
On a sunny day (Tue, 23 Feb 2010 06:44:10 -0800 (PST)) it happened MooseFET
<kensmith_at_rahul.net> wrote in
<4cc9da7d-6f7d-4749-b387-5a2cde7c0f08_at_u15g2000prd.googlegroups.com>:
Quote:
On Feb 23, 3:53 am, Jan Panteltje <pNaonStpealm...@yahoo.com> wrote:
On a sunny day (Mon, 22 Feb 2010 21:16:20 -0600) it happened "RogerN"
re...@midwest.net> wrote in <D-ednWKLu70R1R7WnZ2dnUVZ_gWdn...@earthlink.=
com>:
I'm interested in doing a project both for the practice and to be useful=
.
It would be something like a Battery Tender automatic float charger.
The basic idea is a microcontroller to control based on battery voltage =
and
current. If I understand correctly, you charge at maximum current unt=
il you
reach 14.4V on a 12V battery, then you lower the current to prevent the
voltage from going over 14.4V. After the current reduces to perhaps 0=
.1A,
the charge is terminated and float mode keeps the voltage at 13.2V, if t=
he
voltage goes under 12.6V, the charge cycle is restarted.
My question is what to use to interface the microcontroller to the batte=
ry?
Voltage regulator circuit or what. I need to sense voltage and curren=
t and
control the output. I can come up with something to work but I'm look=
ing
for ideas that might be better than mine.
RogerN
http://panteltje.com/panteltje/pic/pwr_pic/index.html
Beware! When you design a battery charger, someone will always
connect the
battery backwards.
On a sunny day (Mon, 22 Feb 2010 21:16:20 -0600) it happened "RogerN"
re...@midwest.net> wrote in <D-ednWKLu70R1R7WnZ2dnUVZ_gWdn...@earthlink.=
com>:
I'm interested in doing a project both for the practice and to be useful=
.
It would be something like a Battery Tender automatic float charger.
The basic idea is a microcontroller to control based on battery voltage =
and
current. If I understand correctly, you charge at maximum current unt=
il you
reach 14.4V on a 12V battery, then you lower the current to prevent the
voltage from going over 14.4V. After the current reduces to perhaps 0=
.1A,
the charge is terminated and float mode keeps the voltage at 13.2V, if t=
he
voltage goes under 12.6V, the charge cycle is restarted.
My question is what to use to interface the microcontroller to the batte=
ry?
Voltage regulator circuit or what. I need to sense voltage and curren=
t and
control the output. I can come up with something to work but I'm look=
ing
for ideas that might be better than mine.
RogerN
http://panteltje.com/panteltje/pic/pwr_pic/index.html
Beware! When you design a battery charger, someone will always
connect the
battery backwards.
True
So when charging a battery add a diode.
Vladimir Vassilevsky
Guest
Guest
Tue Feb 23, 2010 9:56 pm
Jan Panteltje wrote:
Quote:
On a sunny day (Tue, 23 Feb 2010 06:44:10 -0800 (PST)) it happened MooseFET
kensmith_at_rahul.net> wrote in
4cc9da7d-6f7d-4749-b387-5a2cde7c0f08_at_u15g2000prd.googlegroups.com>:
On Feb 23, 3:53 am, Jan Panteltje <pNaonStpealm...@yahoo.com> wrote:
On a sunny day (Mon, 22 Feb 2010 21:16:20 -0600) it happened "RogerN"
re...@midwest.net> wrote in <D-ednWKLu70R1R7WnZ2dnUVZ_gWdn...@earthlink.=
com>:
I'm interested in doing a project both for the practice and to be useful=
.
It would be something like a Battery Tender automatic float charger.
The basic idea is a microcontroller to control based on battery voltage =
and
current. If I understand correctly, you charge at maximum current unt=
il you
reach 14.4V on a 12V battery, then you lower the current to prevent the
voltage from going over 14.4V. After the current reduces to perhaps 0=
.1A,
the charge is terminated and float mode keeps the voltage at 13.2V, if t=
he
voltage goes under 12.6V, the charge cycle is restarted.
My question is what to use to interface the microcontroller to the batte=
ry?
Voltage regulator circuit or what. I need to sense voltage and curren=
t and
control the output. I can come up with something to work but I'm look=
ing
for ideas that might be better than mine.
RogerN
http://panteltje.com/panteltje/pic/pwr_pic/index.html
Beware! When you design a battery charger, someone will always
connect the
battery backwards.
True
So when charging a battery add a diode.
kensmith_at_rahul.net> wrote in
4cc9da7d-6f7d-4749-b387-5a2cde7c0f08_at_u15g2000prd.googlegroups.com>:
On Feb 23, 3:53 am, Jan Panteltje <pNaonStpealm...@yahoo.com> wrote:
On a sunny day (Mon, 22 Feb 2010 21:16:20 -0600) it happened "RogerN"
re...@midwest.net> wrote in <D-ednWKLu70R1R7WnZ2dnUVZ_gWdn...@earthlink.=
com>:
I'm interested in doing a project both for the practice and to be useful=
.
It would be something like a Battery Tender automatic float charger.
The basic idea is a microcontroller to control based on battery voltage =
and
current. If I understand correctly, you charge at maximum current unt=
il you
reach 14.4V on a 12V battery, then you lower the current to prevent the
voltage from going over 14.4V. After the current reduces to perhaps 0=
.1A,
the charge is terminated and float mode keeps the voltage at 13.2V, if t=
he
voltage goes under 12.6V, the charge cycle is restarted.
My question is what to use to interface the microcontroller to the batte=
ry?
Voltage regulator circuit or what. I need to sense voltage and curren=
t and
control the output. I can come up with something to work but I'm look=
ing
for ideas that might be better than mine.
RogerN
http://panteltje.com/panteltje/pic/pwr_pic/index.html
Beware! When you design a battery charger, someone will always
connect the
battery backwards.
True
So when charging a battery add a diode.
))))))))))))
Nope.
VLV
Jan Panteltje
Guest
Guest
Tue Feb 23, 2010 11:46 pm
On a sunny day (Tue, 23 Feb 2010 14:56:50 -0600) it happened Vladimir
Vassilevsky <nospam_at_nowhere.com> wrote in
<f-edndVkmKOO3BnWnZ2dnUVZ_jadnZ2d_at_giganews.com>:
Quote:
Jan Panteltje wrote:
On a sunny day (Tue, 23 Feb 2010 06:44:10 -0800 (PST)) it happened MooseFET
kensmith_at_rahul.net> wrote in
4cc9da7d-6f7d-4749-b387-5a2cde7c0f08_at_u15g2000prd.googlegroups.com>:
On Feb 23, 3:53 am, Jan Panteltje <pNaonStpealm...@yahoo.com> wrote:
On a sunny day (Mon, 22 Feb 2010 21:16:20 -0600) it happened "RogerN"
re...@midwest.net> wrote in <D-ednWKLu70R1R7WnZ2dnUVZ_gWdn...@earthlink.=
com>:
I'm interested in doing a project both for the practice and to be useful=
.
It would be something like a Battery Tender automatic float charger.
The basic idea is a microcontroller to control based on battery voltage =
and
current. If I understand correctly, you charge at maximum current unt=
il you
reach 14.4V on a 12V battery, then you lower the current to prevent the
voltage from going over 14.4V. After the current reduces to perhaps 0=
.1A,
the charge is terminated and float mode keeps the voltage at 13.2V, if t=
he
voltage goes under 12.6V, the charge cycle is restarted.
My question is what to use to interface the microcontroller to the batte=
ry?
Voltage regulator circuit or what. I need to sense voltage and curren=
t and
control the output. I can come up with something to work but I'm look=
ing
for ideas that might be better than mine.
RogerN
http://panteltje.com/panteltje/pic/pwr_pic/index.html
Beware! When you design a battery charger, someone will always
connect the
battery backwards.
True
So when charging a battery add a diode.
:)))))))))))))
Nope.
VLV
Why not?
Just set the voltage .7 V higher.
Raveninghorde
Guest
Guest
Tue Feb 23, 2010 11:55 pm
On Tue, 23 Feb 2010 22:46:07 GMT, Jan Panteltje
<pNaonStpealmtje_at_yahoo.com> wrote:
Quote:
On a sunny day (Tue, 23 Feb 2010 14:56:50 -0600) it happened Vladimir
Vassilevsky <nospam_at_nowhere.com> wrote in
f-edndVkmKOO3BnWnZ2dnUVZ_jadnZ2d_at_giganews.com>:
Jan Panteltje wrote:
On a sunny day (Tue, 23 Feb 2010 06:44:10 -0800 (PST)) it happened MooseFET
kensmith_at_rahul.net> wrote in
4cc9da7d-6f7d-4749-b387-5a2cde7c0f08_at_u15g2000prd.googlegroups.com>:
On Feb 23, 3:53 am, Jan Panteltje <pNaonStpealm...@yahoo.com> wrote:
On a sunny day (Mon, 22 Feb 2010 21:16:20 -0600) it happened "RogerN"
re...@midwest.net> wrote in <D-ednWKLu70R1R7WnZ2dnUVZ_gWdn...@earthlink.=
com>:
I'm interested in doing a project both for the practice and to be useful=
.
It would be something like a Battery Tender automatic float charger.
The basic idea is a microcontroller to control based on battery voltage =
and
current. If I understand correctly, you charge at maximum current unt=
il you
reach 14.4V on a 12V battery, then you lower the current to prevent the
voltage from going over 14.4V. After the current reduces to perhaps 0=
.1A,
the charge is terminated and float mode keeps the voltage at 13.2V, if t=
he
voltage goes under 12.6V, the charge cycle is restarted.
My question is what to use to interface the microcontroller to the batte=
ry?
Voltage regulator circuit or what. I need to sense voltage and curren=
t and
control the output. I can come up with something to work but I'm look=
ing
for ideas that might be better than mine.
RogerN
http://panteltje.com/panteltje/pic/pwr_pic/index.html
Beware! When you design a battery charger, someone will always
connect the
battery backwards.
True
So when charging a battery add a diode.
:)))))))))))))
Nope.
VLV
Why not?
Just set the voltage .7 V higher.
Vassilevsky <nospam_at_nowhere.com> wrote in
f-edndVkmKOO3BnWnZ2dnUVZ_jadnZ2d_at_giganews.com>:
Jan Panteltje wrote:
On a sunny day (Tue, 23 Feb 2010 06:44:10 -0800 (PST)) it happened MooseFET
kensmith_at_rahul.net> wrote in
4cc9da7d-6f7d-4749-b387-5a2cde7c0f08_at_u15g2000prd.googlegroups.com>:
On Feb 23, 3:53 am, Jan Panteltje <pNaonStpealm...@yahoo.com> wrote:
On a sunny day (Mon, 22 Feb 2010 21:16:20 -0600) it happened "RogerN"
re...@midwest.net> wrote in <D-ednWKLu70R1R7WnZ2dnUVZ_gWdn...@earthlink.=
com>:
I'm interested in doing a project both for the practice and to be useful=
.
It would be something like a Battery Tender automatic float charger.
The basic idea is a microcontroller to control based on battery voltage =
and
current. If I understand correctly, you charge at maximum current unt=
il you
reach 14.4V on a 12V battery, then you lower the current to prevent the
voltage from going over 14.4V. After the current reduces to perhaps 0=
.1A,
the charge is terminated and float mode keeps the voltage at 13.2V, if t=
he
voltage goes under 12.6V, the charge cycle is restarted.
My question is what to use to interface the microcontroller to the batte=
ry?
Voltage regulator circuit or what. I need to sense voltage and curren=
t and
control the output. I can come up with something to work but I'm look=
ing
for ideas that might be better than mine.
RogerN
http://panteltje.com/panteltje/pic/pwr_pic/index.html
Beware! When you design a battery charger, someone will always
connect the
battery backwards.
True
So when charging a battery add a diode.
:)))))))))))))
Nope.
VLV
Why not?
Just set the voltage .7 V higher.
Because the current will flow from the battery into the ground through
the inductor and diode in your circuit and back into the negative of
the battery. PDQ something will smoke.
Grant
Guest
Guest
Tue Feb 23, 2010 11:57 pm
On Tue, 23 Feb 2010 22:46:07 GMT, Jan Panteltje <pNaonStpealmtje_at_yahoo.com> wrote:
Quote:
On a sunny day (Tue, 23 Feb 2010 14:56:50 -0600) it happened Vladimir
Vassilevsky <nospam_at_nowhere.com> wrote in
f-edndVkmKOO3BnWnZ2dnUVZ_jadnZ2d_at_giganews.com>:
Jan Panteltje wrote:
On a sunny day (Tue, 23 Feb 2010 06:44:10 -0800 (PST)) it happened MooseFET
kensmith_at_rahul.net> wrote in
4cc9da7d-6f7d-4749-b387-5a2cde7c0f08_at_u15g2000prd.googlegroups.com>:
On Feb 23, 3:53 am, Jan Panteltje <pNaonStpealm...@yahoo.com> wrote:
On a sunny day (Mon, 22 Feb 2010 21:16:20 -0600) it happened "RogerN"
re...@midwest.net> wrote in <D-ednWKLu70R1R7WnZ2dnUVZ_gWdn...@earthlink.=
com>:
I'm interested in doing a project both for the practice and to be useful=
.
It would be something like a Battery Tender automatic float charger.
The basic idea is a microcontroller to control based on battery voltage =
and
current. If I understand correctly, you charge at maximum current unt=
il you
reach 14.4V on a 12V battery, then you lower the current to prevent the
voltage from going over 14.4V. After the current reduces to perhaps 0=
.1A,
the charge is terminated and float mode keeps the voltage at 13.2V, if t=
he
voltage goes under 12.6V, the charge cycle is restarted.
My question is what to use to interface the microcontroller to the batte=
ry?
Voltage regulator circuit or what. I need to sense voltage and curren=
t and
control the output. I can come up with something to work but I'm look=
ing
for ideas that might be better than mine.
RogerN
http://panteltje.com/panteltje/pic/pwr_pic/index.html
Beware! When you design a battery charger, someone will always
connect the
battery backwards.
True
So when charging a battery add a diode.
:)))))))))))))
Nope.
VLV
Why not?
Just set the voltage .7 V higher.
Vassilevsky <nospam_at_nowhere.com> wrote in
f-edndVkmKOO3BnWnZ2dnUVZ_jadnZ2d_at_giganews.com>:
Jan Panteltje wrote:
On a sunny day (Tue, 23 Feb 2010 06:44:10 -0800 (PST)) it happened MooseFET
kensmith_at_rahul.net> wrote in
4cc9da7d-6f7d-4749-b387-5a2cde7c0f08_at_u15g2000prd.googlegroups.com>:
On Feb 23, 3:53 am, Jan Panteltje <pNaonStpealm...@yahoo.com> wrote:
On a sunny day (Mon, 22 Feb 2010 21:16:20 -0600) it happened "RogerN"
re...@midwest.net> wrote in <D-ednWKLu70R1R7WnZ2dnUVZ_gWdn...@earthlink.=
com>:
I'm interested in doing a project both for the practice and to be useful=
.
It would be something like a Battery Tender automatic float charger.
The basic idea is a microcontroller to control based on battery voltage =
and
current. If I understand correctly, you charge at maximum current unt=
il you
reach 14.4V on a 12V battery, then you lower the current to prevent the
voltage from going over 14.4V. After the current reduces to perhaps 0=
.1A,
the charge is terminated and float mode keeps the voltage at 13.2V, if t=
he
voltage goes under 12.6V, the charge cycle is restarted.
My question is what to use to interface the microcontroller to the batte=
ry?
Voltage regulator circuit or what. I need to sense voltage and curren=
t and
control the output. I can come up with something to work but I'm look=
ing
for ideas that might be better than mine.
RogerN
http://panteltje.com/panteltje/pic/pwr_pic/index.html
Beware! When you design a battery charger, someone will always
connect the
battery backwards.
True
So when charging a battery add a diode.
:)))))))))))))
Nope.
VLV
Why not?
Just set the voltage .7 V higher.
Current flow with reverse battery is in the same direction as charging
current. Series diode just stops battery powering up the charger.
Commercial battery chargers will sense battery voltage then close a
relay it the battery is right way around.
Another option is a reverse diode across the battery terminals to
either blow a fuse or have a polyswitch or lamp to hold back the
current.
Battery voltage sensed via diode can be sloppy due to diode's varying
voltage drop, but might be okay for float use.
Grant.
--
http://bugs.id.au/
Jan Panteltje
Guest
Guest
Wed Feb 24, 2010 12:39 am
On a sunny day (Wed, 24 Feb 2010 09:57:25 +1100) it happened Grant
<g_r_a_n_t__at_bugs.id.au> wrote in <91n8o55ml13l9qadevprasjfhmt5n7f35p_at_4ax.com>:
Quote:
On Tue, 23 Feb 2010 22:46:07 GMT, Jan Panteltje <pNaonStpealmtje_at_yahoo.com> wrote:
On a sunny day (Tue, 23 Feb 2010 14:56:50 -0600) it happened Vladimir
Vassilevsky <nospam_at_nowhere.com> wrote in
f-edndVkmKOO3BnWnZ2dnUVZ_jadnZ2d_at_giganews.com>:
Jan Panteltje wrote:
On a sunny day (Tue, 23 Feb 2010 06:44:10 -0800 (PST)) it happened MooseFET
kensmith_at_rahul.net> wrote in
4cc9da7d-6f7d-4749-b387-5a2cde7c0f08_at_u15g2000prd.googlegroups.com>:
On Feb 23, 3:53 am, Jan Panteltje <pNaonStpealm...@yahoo.com> wrote:
On a sunny day (Mon, 22 Feb 2010 21:16:20 -0600) it happened "RogerN"
re...@midwest.net> wrote in <D-ednWKLu70R1R7WnZ2dnUVZ_gWdn...@earthlink.=
com>:
I'm interested in doing a project both for the practice and to be useful=
.
It would be something like a Battery Tender automatic float charger.
The basic idea is a microcontroller to control based on battery voltage =
and
current. If I understand correctly, you charge at maximum current unt=
il you
reach 14.4V on a 12V battery, then you lower the current to prevent the
voltage from going over 14.4V. After the current reduces to perhaps 0=
.1A,
the charge is terminated and float mode keeps the voltage at 13.2V, if t=
he
voltage goes under 12.6V, the charge cycle is restarted.
My question is what to use to interface the microcontroller to the batte=
ry?
Voltage regulator circuit or what. I need to sense voltage and curren=
t and
control the output. I can come up with something to work but I'm look=
ing
for ideas that might be better than mine.
RogerN
http://panteltje.com/panteltje/pic/pwr_pic/index.html
Beware! When you design a battery charger, someone will always
connect the
battery backwards.
True
So when charging a battery add a diode.
:)))))))))))))
Nope.
VLV
Why not?
Just set the voltage .7 V higher.
Current flow with reverse battery is in the same direction as charging
current. Series diode just stops battery powering up the charger.
Commercial battery chargers will sense battery voltage then close a
relay it the battery is right way around.
Another option is a reverse diode across the battery terminals to
either blow a fuse or have a polyswitch or lamp to hold back the
current.
Battery voltage sensed via diode can be sloppy due to diode's varying
voltage drop, but might be okay for float use.
Grant.
On a sunny day (Tue, 23 Feb 2010 14:56:50 -0600) it happened Vladimir
Vassilevsky <nospam_at_nowhere.com> wrote in
f-edndVkmKOO3BnWnZ2dnUVZ_jadnZ2d_at_giganews.com>:
Jan Panteltje wrote:
On a sunny day (Tue, 23 Feb 2010 06:44:10 -0800 (PST)) it happened MooseFET
kensmith_at_rahul.net> wrote in
4cc9da7d-6f7d-4749-b387-5a2cde7c0f08_at_u15g2000prd.googlegroups.com>:
On Feb 23, 3:53 am, Jan Panteltje <pNaonStpealm...@yahoo.com> wrote:
On a sunny day (Mon, 22 Feb 2010 21:16:20 -0600) it happened "RogerN"
re...@midwest.net> wrote in <D-ednWKLu70R1R7WnZ2dnUVZ_gWdn...@earthlink.=
com>:
I'm interested in doing a project both for the practice and to be useful=
.
It would be something like a Battery Tender automatic float charger.
The basic idea is a microcontroller to control based on battery voltage =
and
current. If I understand correctly, you charge at maximum current unt=
il you
reach 14.4V on a 12V battery, then you lower the current to prevent the
voltage from going over 14.4V. After the current reduces to perhaps 0=
.1A,
the charge is terminated and float mode keeps the voltage at 13.2V, if t=
he
voltage goes under 12.6V, the charge cycle is restarted.
My question is what to use to interface the microcontroller to the batte=
ry?
Voltage regulator circuit or what. I need to sense voltage and curren=
t and
control the output. I can come up with something to work but I'm look=
ing
for ideas that might be better than mine.
RogerN
http://panteltje.com/panteltje/pic/pwr_pic/index.html
Beware! When you design a battery charger, someone will always
connect the
battery backwards.
True
So when charging a battery add a diode.
:)))))))))))))
Nope.
VLV
Why not?
Just set the voltage .7 V higher.
Current flow with reverse battery is in the same direction as charging
current. Series diode just stops battery powering up the charger.
Commercial battery chargers will sense battery voltage then close a
relay it the battery is right way around.
Another option is a reverse diode across the battery terminals to
either blow a fuse or have a polyswitch or lamp to hold back the
current.
Battery voltage sensed via diode can be sloppy due to diode's varying
voltage drop, but might be okay for float use.
Grant.
Oops, you are right!
Thank you for pointing it out.
LOL, I should know, did that reverse protection thing with a thyristor charger.
So what happens when you connect the battery the right way,
the relay comes up,
then you disconnect the battery,
but now the relay stays up, as the charger makes output voltage,
and then reverse connect the battery?
?
Raveninghorde
Guest
Guest
Wed Feb 24, 2010 1:19 am
On Tue, 23 Feb 2010 23:39:08 GMT, Jan Panteltje
<pNaonStpealmtje_at_yahoo.com> wrote:
Quote:
On a sunny day (Wed, 24 Feb 2010 09:57:25 +1100) it happened Grant
g_r_a_n_t__at_bugs.id.au> wrote in <91n8o55ml13l9qadevprasjfhmt5n7f35p_at_4ax.com>:
On Tue, 23 Feb 2010 22:46:07 GMT, Jan Panteltje <pNaonStpealmtje_at_yahoo.com> wrote:
On a sunny day (Tue, 23 Feb 2010 14:56:50 -0600) it happened Vladimir
Vassilevsky <nospam_at_nowhere.com> wrote in
f-edndVkmKOO3BnWnZ2dnUVZ_jadnZ2d_at_giganews.com>:
Jan Panteltje wrote:
On a sunny day (Tue, 23 Feb 2010 06:44:10 -0800 (PST)) it happened MooseFET
kensmith_at_rahul.net> wrote in
4cc9da7d-6f7d-4749-b387-5a2cde7c0f08_at_u15g2000prd.googlegroups.com>:
On Feb 23, 3:53 am, Jan Panteltje <pNaonStpealm...@yahoo.com> wrote:
On a sunny day (Mon, 22 Feb 2010 21:16:20 -0600) it happened "RogerN"
re...@midwest.net> wrote in <D-ednWKLu70R1R7WnZ2dnUVZ_gWdn...@earthlink.=
com>:
I'm interested in doing a project both for the practice and to be useful=
.
It would be something like a Battery Tender automatic float charger.
The basic idea is a microcontroller to control based on battery voltage =
and
current. If I understand correctly, you charge at maximum current unt=
il you
reach 14.4V on a 12V battery, then you lower the current to prevent the
voltage from going over 14.4V. After the current reduces to perhaps 0=
.1A,
the charge is terminated and float mode keeps the voltage at 13.2V, if t=
he
voltage goes under 12.6V, the charge cycle is restarted.
My question is what to use to interface the microcontroller to the batte=
ry?
Voltage regulator circuit or what. I need to sense voltage and curren=
t and
control the output. I can come up with something to work but I'm look=
ing
for ideas that might be better than mine.
RogerN
http://panteltje.com/panteltje/pic/pwr_pic/index.html
Beware! When you design a battery charger, someone will always
connect the
battery backwards.
True
So when charging a battery add a diode.
:)))))))))))))
Nope.
VLV
Why not?
Just set the voltage .7 V higher.
Current flow with reverse battery is in the same direction as charging
current. Series diode just stops battery powering up the charger.
Commercial battery chargers will sense battery voltage then close a
relay it the battery is right way around.
Another option is a reverse diode across the battery terminals to
either blow a fuse or have a polyswitch or lamp to hold back the
current.
Battery voltage sensed via diode can be sloppy due to diode's varying
voltage drop, but might be okay for float use.
Grant.
Oops, you are right!
Thank you for pointing it out.
LOL, I should know, did that reverse protection thing with a thyristor charger.
So what happens when you connect the battery the right way,
the relay comes up,
then you disconnect the battery,
but now the relay stays up, as the charger makes output voltage,
and then reverse connect the battery?
?
g_r_a_n_t__at_bugs.id.au> wrote in <91n8o55ml13l9qadevprasjfhmt5n7f35p_at_4ax.com>:
On Tue, 23 Feb 2010 22:46:07 GMT, Jan Panteltje <pNaonStpealmtje_at_yahoo.com> wrote:
On a sunny day (Tue, 23 Feb 2010 14:56:50 -0600) it happened Vladimir
Vassilevsky <nospam_at_nowhere.com> wrote in
f-edndVkmKOO3BnWnZ2dnUVZ_jadnZ2d_at_giganews.com>:
Jan Panteltje wrote:
On a sunny day (Tue, 23 Feb 2010 06:44:10 -0800 (PST)) it happened MooseFET
kensmith_at_rahul.net> wrote in
4cc9da7d-6f7d-4749-b387-5a2cde7c0f08_at_u15g2000prd.googlegroups.com>:
On Feb 23, 3:53 am, Jan Panteltje <pNaonStpealm...@yahoo.com> wrote:
On a sunny day (Mon, 22 Feb 2010 21:16:20 -0600) it happened "RogerN"
re...@midwest.net> wrote in <D-ednWKLu70R1R7WnZ2dnUVZ_gWdn...@earthlink.=
com>:
I'm interested in doing a project both for the practice and to be useful=
.
It would be something like a Battery Tender automatic float charger.
The basic idea is a microcontroller to control based on battery voltage =
and
current. If I understand correctly, you charge at maximum current unt=
il you
reach 14.4V on a 12V battery, then you lower the current to prevent the
voltage from going over 14.4V. After the current reduces to perhaps 0=
.1A,
the charge is terminated and float mode keeps the voltage at 13.2V, if t=
he
voltage goes under 12.6V, the charge cycle is restarted.
My question is what to use to interface the microcontroller to the batte=
ry?
Voltage regulator circuit or what. I need to sense voltage and curren=
t and
control the output. I can come up with something to work but I'm look=
ing
for ideas that might be better than mine.
RogerN
http://panteltje.com/panteltje/pic/pwr_pic/index.html
Beware! When you design a battery charger, someone will always
connect the
battery backwards.
True
So when charging a battery add a diode.
:)))))))))))))
Nope.
VLV
Why not?
Just set the voltage .7 V higher.
Current flow with reverse battery is in the same direction as charging
current. Series diode just stops battery powering up the charger.
Commercial battery chargers will sense battery voltage then close a
relay it the battery is right way around.
Another option is a reverse diode across the battery terminals to
either blow a fuse or have a polyswitch or lamp to hold back the
current.
Battery voltage sensed via diode can be sloppy due to diode's varying
voltage drop, but might be okay for float use.
Grant.
Oops, you are right!
Thank you for pointing it out.
LOL, I should know, did that reverse protection thing with a thyristor charger.
So what happens when you connect the battery the right way,
the relay comes up,
then you disconnect the battery,
but now the relay stays up, as the charger makes output voltage,
and then reverse connect the battery?
?
I would pull the output up to +24V with a resistor so when the battery
is removed there is a clear signal. Detect +24V and drop out the
relay.
Grant
Guest
Guest
Wed Feb 24, 2010 2:10 am
On Tue, 23 Feb 2010 23:39:08 GMT, Jan Panteltje <pNaonStpealmtje_at_yahoo.com> wrote:
Quote:
On a sunny day (Wed, 24 Feb 2010 09:57:25 +1100) it happened Grant
g_r_a_n_t__at_bugs.id.au> wrote in <91n8o55ml13l9qadevprasjfhmt5n7f35p_at_4ax.com>:
On Tue, 23 Feb 2010 22:46:07 GMT, Jan Panteltje <pNaonStpealmtje_at_yahoo.com> wrote:
On a sunny day (Tue, 23 Feb 2010 14:56:50 -0600) it happened Vladimir
Vassilevsky <nospam_at_nowhere.com> wrote in
f-edndVkmKOO3BnWnZ2dnUVZ_jadnZ2d_at_giganews.com>:
Jan Panteltje wrote:
On a sunny day (Tue, 23 Feb 2010 06:44:10 -0800 (PST)) it happened MooseFET
kensmith_at_rahul.net> wrote in
4cc9da7d-6f7d-4749-b387-5a2cde7c0f08_at_u15g2000prd.googlegroups.com>:
On Feb 23, 3:53 am, Jan Panteltje <pNaonStpealm...@yahoo.com> wrote:
On a sunny day (Mon, 22 Feb 2010 21:16:20 -0600) it happened "RogerN"
re...@midwest.net> wrote in <D-ednWKLu70R1R7WnZ2dnUVZ_gWdn...@earthlink.=
com>:
I'm interested in doing a project both for the practice and to be useful=
.
It would be something like a Battery Tender automatic float charger.
The basic idea is a microcontroller to control based on battery voltage =
and
current. If I understand correctly, you charge at maximum current unt=
il you
reach 14.4V on a 12V battery, then you lower the current to prevent the
voltage from going over 14.4V. After the current reduces to perhaps 0=
.1A,
the charge is terminated and float mode keeps the voltage at 13.2V, if t=
he
voltage goes under 12.6V, the charge cycle is restarted.
My question is what to use to interface the microcontroller to the batte=
ry?
Voltage regulator circuit or what. I need to sense voltage and curren=
t and
control the output. I can come up with something to work but I'm look=
ing
for ideas that might be better than mine.
RogerN
http://panteltje.com/panteltje/pic/pwr_pic/index.html
Beware! When you design a battery charger, someone will always
connect the
battery backwards.
True
So when charging a battery add a diode.
:)))))))))))))
Nope.
VLV
Why not?
Just set the voltage .7 V higher.
Current flow with reverse battery is in the same direction as charging
current. Series diode just stops battery powering up the charger.
Commercial battery chargers will sense battery voltage then close a
relay it the battery is right way around.
Another option is a reverse diode across the battery terminals to
either blow a fuse or have a polyswitch or lamp to hold back the
current.
Battery voltage sensed via diode can be sloppy due to diode's varying
voltage drop, but might be okay for float use.
Grant.
Oops, you are right!
Thank you for pointing it out.
LOL, I should know, did that reverse protection thing with a thyristor charger.
So what happens when you connect the battery the right way,
the relay comes up,
then you disconnect the battery,
but now the relay stays up, as the charger makes output voltage,
and then reverse connect the battery?
?
g_r_a_n_t__at_bugs.id.au> wrote in <91n8o55ml13l9qadevprasjfhmt5n7f35p_at_4ax.com>:
On Tue, 23 Feb 2010 22:46:07 GMT, Jan Panteltje <pNaonStpealmtje_at_yahoo.com> wrote:
On a sunny day (Tue, 23 Feb 2010 14:56:50 -0600) it happened Vladimir
Vassilevsky <nospam_at_nowhere.com> wrote in
f-edndVkmKOO3BnWnZ2dnUVZ_jadnZ2d_at_giganews.com>:
Jan Panteltje wrote:
On a sunny day (Tue, 23 Feb 2010 06:44:10 -0800 (PST)) it happened MooseFET
kensmith_at_rahul.net> wrote in
4cc9da7d-6f7d-4749-b387-5a2cde7c0f08_at_u15g2000prd.googlegroups.com>:
On Feb 23, 3:53 am, Jan Panteltje <pNaonStpealm...@yahoo.com> wrote:
On a sunny day (Mon, 22 Feb 2010 21:16:20 -0600) it happened "RogerN"
re...@midwest.net> wrote in <D-ednWKLu70R1R7WnZ2dnUVZ_gWdn...@earthlink.=
com>:
I'm interested in doing a project both for the practice and to be useful=
.
It would be something like a Battery Tender automatic float charger.
The basic idea is a microcontroller to control based on battery voltage =
and
current. If I understand correctly, you charge at maximum current unt=
il you
reach 14.4V on a 12V battery, then you lower the current to prevent the
voltage from going over 14.4V. After the current reduces to perhaps 0=
.1A,
the charge is terminated and float mode keeps the voltage at 13.2V, if t=
he
voltage goes under 12.6V, the charge cycle is restarted.
My question is what to use to interface the microcontroller to the batte=
ry?
Voltage regulator circuit or what. I need to sense voltage and curren=
t and
control the output. I can come up with something to work but I'm look=
ing
for ideas that might be better than mine.
RogerN
http://panteltje.com/panteltje/pic/pwr_pic/index.html
Beware! When you design a battery charger, someone will always
connect the
battery backwards.
True
So when charging a battery add a diode.
:)))))))))))))
Nope.
VLV
Why not?
Just set the voltage .7 V higher.
Current flow with reverse battery is in the same direction as charging
current. Series diode just stops battery powering up the charger.
Commercial battery chargers will sense battery voltage then close a
relay it the battery is right way around.
Another option is a reverse diode across the battery terminals to
either blow a fuse or have a polyswitch or lamp to hold back the
current.
Battery voltage sensed via diode can be sloppy due to diode's varying
voltage drop, but might be okay for float use.
Grant.
Oops, you are right!
Thank you for pointing it out.
LOL, I should know, did that reverse protection thing with a thyristor charger.
So what happens when you connect the battery the right way,
the relay comes up,
then you disconnect the battery,
but now the relay stays up, as the charger makes output voltage,
and then reverse connect the battery?
?
Relay drops out as soon as charging current collapses or voltage below
minimum for battery size; for example, disconnect at below 16V for a 24V
battery.
Grant.
--
http://bugs.id.au/
elektroda.net NewsGroups Forum Index - Electronics Design - Project Float Charger
