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| PeterD... |
 Posted: Sat Oct 03, 2009 7:59 am |
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Guest
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On Sat, 03 Oct 2009 09:55:18 -0400, Jamie
<jamie_ka1lpa_not_valid_after_ka1lpa_ at (no spam) charter.net> wrote:
[quote:caa37b17a5]
Most likely the computer is already using a pwm scheme to control the
alternator.
[/quote:caa37b17a5]
In chrysler products, it is... (in virtually all alternators they use
PWM...
[quote:caa37b17a5]
Since you indicate that the cpu is controlling the field, we can only
assume it also must regulate the voltage for the alternator ?
[/quote:caa37b17a5]
The regulator is part of the ECM's job.
[quote:caa37b17a5]I
find that a little disturbing my self actually, unless this is a safety
control system to shut down the alternator in the event of run away,
which is more plausible ?
[/quote:caa37b17a5]
Reduced costs was teh reason, there were spare CPU cycles, the
additional circutry was minimal.
[quote:caa37b17a5]
In any case, if the computer really is monitoring this voltage and
regulating it,
[/quote:caa37b17a5]
I assumed that OP was going to remove the entire ECM circuit and drive
the alternator directly (perhaps on a different platform?) He will
have to consider the fact that the ECM will go nuts when it tries to
regulate voltage and can't... <bg>
[quote:caa37b17a5]I don't think you'll do much with this since it's likely
the monitor point is internal and changing the voltage will most likely
alert the system of a alternator regulation failure and shut it down!.
[/quote:caa37b17a5]
Well the ECM will set a code or two... Might go into a limp-home mode.
Not sure it would shut the engine down, and since the OP is removing
the ECM to alternator connection (again, an assumption) it can't shut
the alternator down...
[quote:caa37b17a5]
You could try if you wish, to insert a diode in series to the CPU with
a cap on the other side. If the voltage is truly being monitored
internally to be regulated, this should force the ECM to pump it up
another .6 volts of so. Or, there maybe a another input like being used
for this which you can do the same thing.
It's your vehicle's electronics, go for it.
[/quote:caa37b17a5]
The real question is WHY does the OP want to do this? Is he using a
Chrysler alternator on a different platform? |
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| Paul Hovnanian P.E.... |
| Posted: Sat Oct 03, 2009 9:07 pm |
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Joerg wrote:
[quote:ba180c64a2]
[snip]
I usually go above the audio threshold but mind animals (thery hear very
much higher than we do). I don't know alternators enough to say whether
they'd like such direct PWM or whether current-sink switcher plus filter
would be better. PWM in the audio range could cause a nasty buzz on the
stereo.
[/quote:ba180c64a2]
Back in 'the old days', electromechanical regulators were basically PWM
implemented with a relay. These operated at the lower end of the audio
range, with no adverse effects to the radios of the day. The battery
makes an excellent low pass filter.
--
Paul Hovnanian mailto:Paul at (no spam) Hovnanian.com
------------------------------------------------------------------
When cryptography is outlawed, bayl bhgynjf jvyy unir cevinpl.
-- Etaoin Shrdlu |
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| Paul Hovnanian P.E.... |
| Posted: Sat Oct 03, 2009 9:16 pm |
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Joerg wrote:
[quote:5455eb4dec]
[snip]
The epitome of frugality was my Citroen 2CV.
[/quote:5455eb4dec]
Cute car. I would have bought one if they were offered with a V8 option.
;-)
--
Paul Hovnanian mailto:Paul at (no spam) Hovnanian.com
------------------------------------------------------------------
It is not enough to succeed. Others must fail. -- Gore Vidal |
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| Michael Robinson... |
| Posted: Mon Oct 05, 2009 10:39 am |
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"Paul Hovnanian P.E." <paul at (no spam) hovnanian.com> wrote in message
news:4AC81393.EE7036A0 at (no spam) hovnanian.com...
[quote:df2951e4d5]Joerg wrote:
[snip]
The epitome of frugality was my Citroen 2CV.
Cute car. I would have bought one if they were offered with a V8 option.
;-)
--
Paul Hovnanian mailto:Paul at (no spam) Hovnanian.com
[/quote:df2951e4d5]
You know why they were called 2CV, don't you?
Deux Chevaux -- Two Horsepower. |
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| Joerg... |
| Posted: Mon Oct 05, 2009 11:03 am |
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Michael Robinson wrote:
[quote:0b008d09bf]"Paul Hovnanian P.E." <paul at (no spam) hovnanian.com> wrote in message
news:4AC81393.EE7036A0 at (no spam) hovnanian.com...
Joerg wrote:
[snip]
The epitome of frugality was my Citroen 2CV.
Cute car. I would have bought one if they were offered with a V8 option.
;-)
--
Paul Hovnanian mailto:Paul at (no spam) Hovnanian.com
You know why they were called 2CV, don't you?
Deux Chevaux -- Two Horsepower.
[/quote:0b008d09bf]
Hey, mine had 16 horses. But two cylinders, around 430cc grand total.
*VROOOOM*
--
Regards, Joerg
http://www.analogconsultants.com/
"gmail" domain blocked because of excessive spam.
Use another domain or send PM. |
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| Fred Abse... |
| Posted: Sat Oct 10, 2009 10:03 am |
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On Sat, 03 Oct 2009 15:56:05 -0700, Joerg wrote:
[quote:c1233c4d7f]Not even safety belts but I put good ones in there.
[/quote:c1233c4d7f]
Where on earth did you find something solid enough to attach them to?
--
"Electricity is of two kinds, positive and negative. The difference
is, I presume, that one comes a little more expensive, but is more
durable; the other is a cheaper thing, but the moths get into it."
(Stephen Leacock) |
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| Fred Abse... |
| Posted: Sat Oct 10, 2009 10:03 am |
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On Sat, 03 Oct 2009 15:59:43 -0700, Jim Thompson wrote:
[quote:98aed950d8]An accident waiting for a location ?
[/quote:98aed950d8]
Not much more so than a Dauphine, IMO.
<Ducks for cover>
--
"Electricity is of two kinds, positive and negative. The difference
is, I presume, that one comes a little more expensive, but is more
durable; the other is a cheaper thing, but the moths get into it."
(Stephen Leacock) |
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| Jim Thompson... |
| Posted: Sat Oct 10, 2009 10:09 am |
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On Sat, 10 Oct 2009 09:03:03 -0700, Fred Abse
<excretatauris at (no spam) invalid.invalid> wrote:
[quote:8b52afeea5]On Sat, 03 Oct 2009 15:56:05 -0700, Joerg wrote:
Not even safety belts but I put good ones in there.
Where on earth did you find something solid enough to attach them to?
[/quote:8b52afeea5]
For my '61 Dauphine I used HUGE fender washers above and below the
floor panels. (Lap belts only... before shoulder belts were available
for passenger vehicles.)
...Jim Thompson
--
| James E.Thompson, CTO | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |
I love to cook with wine. Sometimes I even put it in the food. |
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| Jim Thompson... |
| Posted: Sat Oct 10, 2009 10:11 am |
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On Sat, 10 Oct 2009 09:03:04 -0700, Fred Abse
<excretatauris at (no spam) invalid.invalid> wrote:
[quote:14f64140ed]On Sat, 03 Oct 2009 15:59:43 -0700, Jim Thompson wrote:
An accident waiting for a location ?:-)
Not much more so than a Dauphine, IMO.
Ducks for cover
[/quote:14f64140ed]
Probably so. Though, in the eight years I owned it, not a single
accident... except for a Boston yo-yo that overshot a traffic light
and backed up into me, scratching the bumper bars.
...Jim Thompson
--
| James E.Thompson, CTO | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |
I love to cook with wine. Sometimes I even put it in the food. |
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| Joerg... |
| Posted: Thu Oct 15, 2009 2:58 pm |
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Fred Abse wrote:
[quote:2552f8e069]On Sat, 03 Oct 2009 15:56:05 -0700, Joerg wrote:
Not even safety belts but I put good ones in there.
Where on earth did you find something solid enough to attach them to?
[/quote:2552f8e069]
Actually the old 2CV had a rather good classical frame and they were
prepared for belts. Probably because some countries into which it was
exported demanded that.
--
Regards, Joerg
http://www.analogconsultants.com/
"gmail" domain blocked because of excessive spam.
Use another domain or send PM. |
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| Joerg... |
| Posted: Thu Oct 15, 2009 3:11 pm |
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Guest
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Jim Thompson wrote:
[quote:5c98d7aff3]On Sat, 10 Oct 2009 09:03:04 -0700, Fred Abse
excretatauris at (no spam) invalid.invalid> wrote:
On Sat, 03 Oct 2009 15:59:43 -0700, Jim Thompson wrote:
An accident waiting for a location ?
Not much more so than a Dauphine, IMO.
Ducks for cover
Probably so. Though, in the eight years I owned it, not a single
accident... except for a Boston yo-yo that overshot a traffic light
and backed up into me, scratching the bumper bars.
[/quote:5c98d7aff3]
I had an Audi Fox crash into the rear left fender. He needed a new
headlight, turn signal and all sorts of other things. Me:
Took off fender because car would otherwise not move. Required small
screwdriver and starter crank, done right there in the intersection, two
minutes. Threw it onto back seat, drove home. Opened a beer, donned
headphones, played Led Zeppelin, pounded the inside of the fender with a
round mallet. Painted the outside, let it dry. Opened another beer.
Mounted it back on the car. Good as new.
--
Regards, Joerg
http://www.analogconsultants.com/
"gmail" domain blocked because of excessive spam.
Use another domain or send PM. |
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| Rheilly Phoull... |
| Posted: Thu Oct 15, 2009 6:56 pm |
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Guest
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"Joerg" <invalid at (no spam) invalid.invalid> wrote in message
news:7jphh5F3605foU1 at (no spam) mid.individual.net...
[quote:46fa528eaf]Jim Thompson wrote:
On Sat, 10 Oct 2009 09:03:04 -0700, Fred Abse
excretatauris at (no spam) invalid.invalid> wrote:
On Sat, 03 Oct 2009 15:59:43 -0700, Jim Thompson wrote:
An accident waiting for a location ?
Not much more so than a Dauphine, IMO.
Ducks for cover
Probably so. Though, in the eight years I owned it, not a single
accident... except for a Boston yo-yo that overshot a traffic light
and backed up into me, scratching the bumper bars.
I had an Audi Fox crash into the rear left fender. He needed a new
headlight, turn signal and all sorts of other things. Me:
Took off fender because car would otherwise not move. Required small
screwdriver and starter crank, done right there in the intersection, two
minutes. Threw it onto back seat, drove home. Opened a beer, donned
headphones, played Led Zeppelin, pounded the inside of the fender with a
round mallet. Painted the outside, let it dry. Opened another beer.
Mounted it back on the car. Good as new.
--
Regards, Joerg
[/quote:46fa528eaf]
Heh, I used to smirk when I saw them until a whiles back I came across a
group of them in the outback. I was impressed with the solid frame and the
ability to dismantle and replace just about everything with a couple of
tools.
magic little vehicle !!
--
Cheers ............. Rheilly P |
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| Joerg... |
| Posted: Thu Oct 15, 2009 7:58 pm |
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Guest
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Rheilly Phoull wrote:
[quote:7a6e953aed]"Joerg" <invalid at (no spam) invalid.invalid> wrote in message
news:7jphh5F3605foU1 at (no spam) mid.individual.net...
Jim Thompson wrote:
On Sat, 10 Oct 2009 09:03:04 -0700, Fred Abse
excretatauris at (no spam) invalid.invalid> wrote:
On Sat, 03 Oct 2009 15:59:43 -0700, Jim Thompson wrote:
An accident waiting for a location ?
Not much more so than a Dauphine, IMO.
Ducks for cover
Probably so. Though, in the eight years I owned it, not a single
accident... except for a Boston yo-yo that overshot a traffic light
and backed up into me, scratching the bumper bars.
I had an Audi Fox crash into the rear left fender. He needed a new
headlight, turn signal and all sorts of other things. Me:
Took off fender because car would otherwise not move. Required small
screwdriver and starter crank, done right there in the intersection, two
minutes. Threw it onto back seat, drove home. Opened a beer, donned
headphones, played Led Zeppelin, pounded the inside of the fender with a
round mallet. Painted the outside, let it dry. Opened another beer.
Mounted it back on the car. Good as new.
--
Regards, Joerg
Heh, I used to smirk when I saw them until a whiles back I came across a
group of them in the outback. I was impressed with the solid frame and the
ability to dismantle and replace just about everything with a couple of
tools.
magic little vehicle !!
[/quote:7a6e953aed]
In the outback is where they really excel. Several guys tried to get ham
radio gear to a fielday site. Pouring rain, all muddy, got stuck. Here
was me with my old Citroen 2CV. Sawed off a beefy stick of wood, a few
guys lifted the Citroen's front, I slid it under the wheel mounts that
were fully extended. Almost if they were made for that. Loaded the stuff
into the back and the Citroen plowed through, the back sliding along on
the mud like a fishtail. The car is totally flat and clean underneath,
else I'd have gotten stuck like all the others.
--
Regards, Joerg
http://www.analogconsultants.com/
"gmail" domain blocked because of excessive spam.
Use another domain or send PM. |
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| David Lesher... |
| Posted: Sun Nov 01, 2009 9:16 pm |
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Guest
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"Paul Hovnanian P.E." <paul at (no spam) hovnanian.com> writes:
[quote]Joerg wrote:
[snip]
The epitome of frugality was my Citroen 2CV.
Cute car. I would have bought one if they were offered with a V8 option.
[/quote]
They came in a 4WD version; it had complete 2nd engine/transmission
for the rear wheels.
--
A host is a host from coast to coast.................wb8foz at (no spam) nrk.com
& no one will talk to a host that's close........[v].(301) 56-LINUX
Unless the host (that isn't close).........................pob 1433
is busy, hung or dead....................................20915-1433 |
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| David Lesher... |
| Posted: Sun Nov 01, 2009 9:24 pm |
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Guest
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Jim Thompson <To-Email-Use-The-Envelope-Icon at (no spam) My-Web-Site.com> writes:
[quote]Alternators often run at 6-7X engine RPM's.
...Jim Thompson
[/quote]
I seem to recall that car alternators were geared [well, pullyed] to spin
far faster than generators. Does that agree with your knowledge?
[Wound armature generators have far lower rpm limits than an alternator
with smaller, tighter, windings.]
--
A host is a host from coast to coast.................wb8foz at (no spam) nrk.com
& no one will talk to a host that's close........[v].(301) 56-LINUX
Unless the host (that isn't close).........................pob 1433
is busy, hung or dead....................................20915-1433 |
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