dwh
Tail-End Charlie
Electric chainsaw!
DC-DC battery charger under hood?
- Thread starter msand1977
- Start date
Electric chainsaw!
Much higher losses than you think if you actually measure it. The rating on the box is the most optimistic, best possible combination of variables.
And this "solution" is not cheaper for equivalent quality.
HahaHow you must view yourself
How your message actually appears
Mommy! Mommy! He started it first! I just had to be angry and insulting to everyone who disagrees with me!! Not my fault!!
Good efforts
You win
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I shall add one more thing
Originally dc-dc was introduced into the market due to smart alternator
And this is because traditional alternator has fixed output voltage just like a dc-dc without current limitation.
A smart alternator has variable voltage output. The -vehicle control how much power alternator generates. And this creates a problem that the dc-dc charge is designed to solve.
I think I have explained myself very clearly in precious posts.
Some very obvious conflict of interest in this thread.
Cheers
Martin
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Originally dc-dc was introduced into the market due to smart alternator
And this is because traditional alternator has fixed output voltage just like a dc-dc without current limitation.
A smart alternator has variable voltage output. The -vehicle control how much power alternator generates. And this creates a problem that the dc-dc charge is designed to solve.
I think I have explained myself very clearly in precious posts.
Some very obvious conflict of interest in this thread.
Cheers
Martin
Sent from my LG-H870DS using Tapatalk
DiploStrat
Expedition Leader
I think that this statement would come as a shock to Charles Sterling, Sr., an early developer of B2B or DC-DC.
The original purpose was to get the voltage up.
Enjoy!
in general I agreed with him. And the videos you posted supports my points that dc-dc charger is used to solve a problem caused by weak alternator that the output voltage is not optimal.this can be cause by a weak alternator or a smart alternator
It should be noted that many cars nowadays comes with poweful alternator. My diesels car comes with 165amps alternator with an peak charging output of 14.7v. It is very obvious that based on Sterling's statement that I absolutely do not need anything extra.
Does your alternator output at 14.0 volt? Then you may need a dc-dc or replace the alternator.
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And who is this guy in the video.
I am not an expert but only know the basic but I don't think he knows much.
Look I think it is valuable that you posted these videos (and thank you for that)
I strongly encourage whoever reading this thread and thinking of buying a Stirling product to watch the above videos and then decides themselves.
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I am not an expert but only know the basic but I don't think he knows much.
Look I think it is valuable that you posted these videos (and thank you for that)
I strongly encourage whoever reading this thread and thinking of buying a Stirling product to watch the above videos and then decides themselves.
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Again, no. Many generations of such devices were produced long before cars had electronics in engines, never mind extreme MPG mandates.
> traditional alternator has fixed output voltage just like a dc-dc without current limitation
No decent DCDC charger has ever had fixed output voltage, and only the most expensive have current limiting.
I really don't know where you get this stuff?
> A smart alternator has variable voltage output.
Actually a function of the VR, which is separate from the alt itself.
> The vehicle control how much power alternator generates.
No.
> And this creates a problem that the dc-dc charge is designed to solve.
No, there are many other causes of problems they can solve. I often use them where alternators aren't even used, just not a significant enough source of power to bother with in many use cases.
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FYI in my last communications with Charles - he is very responsive to informed questions and support issues - he indicated a 180A unit was being added to the BB line.
This will be very useful for situations where I've had to stack more than two BBW12120 units to get enough charge output into large LFP banks.
Edit: now in the vdo he says 240A, even better!
Note he should have used AH not A units discussing the House bank capacity.
This will be very useful for situations where I've had to stack more than two BBW12120 units to get enough charge output into large LFP banks.
Edit: now in the vdo he says 240A, even better!
Note he should have used AH not A units discussing the House bank capacity.
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ducktapeguy
Adventurer
I'm no expert in this field, so pardon the dumb question, but I have been doing a lot of reading on this subject lately for my own application. Has anyone ever developed a smart voltage regulator that can mimic a DC/DC charger profile? Most alternators should have more than enough power to charge a large battery bank, it's just limited by the controller (in most cases, the VR). Seems like it would be easy enough to have a microprocessor controlled regulator that can deliver the optimum charging profile without the need for a B2B charger. This would eliminate the need for a step up converter since the voltage can easily be controlled directly to whatever it needs to be.
DaveInDenver
Middle Income Semi-Redneck
Modern smart alternators are kind of there, in effect doing a 2-stage profile going to a float when the battery appears to be topped. The next step would be to use an even smarter alternator that does a real 3-stage profile. It's just how complex it needs to be and from a manufacturer's standpoint this much effort isn't justified cost for 99% of owners with stock type flooded batteries in typical use.
This is the problem that DC-DC supplies are trying to solve with respect to an aux battery and loads that the truck doesn't understand. The truck only is expected to start, have headlights and stock loads and so the control system is designed to react to those conditions. It doesn't know explicitly what to do about winches and fridges, so it falls back to implicit decisions based on the parameters it was told by the engineers who designed it.
So you could in theory just replace the OEM alternator controller/regulator with your smart(er) controller. But this isn't practical probably with the close integration with other vehicle systems. Maybe, not, I dunno. It's probably easier to just stick with a DC-DC supply if you need it or use a second alternator that runs your house load.
This is the problem that DC-DC supplies are trying to solve with respect to an aux battery and loads that the truck doesn't understand. The truck only is expected to start, have headlights and stock loads and so the control system is designed to react to those conditions. It doesn't know explicitly what to do about winches and fridges, so it falls back to implicit decisions based on the parameters it was told by the engineers who designed it.
So you could in theory just replace the OEM alternator controller/regulator with your smart(er) controller. But this isn't practical probably with the close integration with other vehicle systems. Maybe, not, I dunno. It's probably easier to just stick with a DC-DC supply if you need it or use a second alternator that runs your house load.
DiploStrat
Expedition Leader
That is exactly what GM does on the Chevrolet Silverado line. Can't speak to other makes and models.
In the case of Chevrolet trucks, it appears that the alternator has a built in 13.9v regulator which is, in turn, overridden by the vehicle's electrical system as needed. If the on board computer fails, then the charging system reverts to the internal regulator. Works very well, and is one reason why I dismounted a Sterling Alternator to Battery charger (A23B) and simply went with an intelligent relay.
The reason that this thread is degenerating into a food fight is that folk are confusing ends and means.
-- The end is to charge the battery by providing the appropriate combination of amperage and voltage.
-- The source (in this case) is the vehicle's alternator.
-- The means are manual switches, ignition controlled relays, intelligent relays, external voltage regulators or adjusters, independent add on alternator/regulator combos, and, of course, battery to battery chargers. (There may be one or two I missed.)
As someone noted, there is no single solution.
I am updating my paper on this, so read this and please comment: https://cookfb.files.wordpress.com/2016/09/dual-battery-slides-2016.pdf
(And note that I do publish my sources.)
DiploStrat
Expedition Leader
Worth noting in all of this that we are assuming that the vehicle's alternator can produce adequate output, call it 100A @ 12v.
What we are arguing about the the voltage(s).
None of this matters if the alternator does not put out, or cannot be tricked into putting out adequate amperage.
What we are arguing about the the voltage(s).
None of this matters if the alternator does not put out, or cannot be tricked into putting out adequate amperage.
You got me wrong.
Use a alternator to charge a battery has no current limitation. For example optima battery.
Anyway maybe you should watch this sterling videos. Part one. What he says supports mine. Not yours.
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