Yes of course..
Solar panel charge 12 volts battery, it's like a tank, on this bat I connect a DC AC Converter like this :
Amazon.com : 300W Car DC 12V to AC 220V USB Power Inverter Adapter : Vehicle Power Inverters : Electronics
and then I connect Li Ion charger on this converter..
I hope it is clear enough.
Phil.
Attachments
For recharge one Li Ion, it take 30 minutes with charger 230 v and 80 watts uptake..
How with a converter 12/230 volt ? I don't know.
Rough math tells me that the demand from the 12 volt battery to feed the 230 volt inverter to supply the Li Ion charger will be ~7 amps. (NOT including the losses in the inverter and the Li Ion charger) Add another 500 mA.. 7.5 amps
You state it takes 1/2Hr. to fully charge each battery. (2 batteries) Figure 1 aHr. @ 7.5 amps..
If you don't plan to operate anything else from the 12 volt battery, figure the minimum battery size at 4 times this amount.. 30 aHr. This gives you a reasonably safe discharge level for a flooded cell lead acid battery. (25%)
Now you must replace the power that you use..
When charging a lead acid battery, you automatically lose 20% of the charge. Now you need to replace 9 aHr. back to the 12 volt battery..
I'll figure 2 hrs. of good sunlight in a day, which is possibly more than you would ever receive on a good day in December.. (Use the link I posted to figure that)
Divide what you need (9 aHr.) by the amount of good sunlight. (2) You would need to collect 4.5 aHr. per hour. Working voltage (12 volts) multiplied by needed current (4.5).. 54 watts of panel. I would round to 60 watts..
Rough estimate but close.. Oh, and you need a charge controller between the battery and the panel..
How with a converter 12/230 volt ? I don't know.
Rough math tells me that the demand from the 12 volt battery to feed the 230 volt inverter to supply the Li Ion charger will be ~7 amps. (NOT including the losses in the inverter and the Li Ion charger) Add another 500 mA.. 7.5 amps
You state it takes 1/2Hr. to fully charge each battery. (2 batteries) Figure 1 aHr. @ 7.5 amps..
If you don't plan to operate anything else from the 12 volt battery, figure the minimum battery size at 4 times this amount.. 30 aHr. This gives you a reasonably safe discharge level for a flooded cell lead acid battery. (25%)
Now you must replace the power that you use..
When charging a lead acid battery, you automatically lose 20% of the charge. Now you need to replace 9 aHr. back to the 12 volt battery..
I'll figure 2 hrs. of good sunlight in a day, which is possibly more than you would ever receive on a good day in December.. (Use the link I posted to figure that)
Divide what you need (9 aHr.) by the amount of good sunlight. (2) You would need to collect 4.5 aHr. per hour. Working voltage (12 volts) multiplied by needed current (4.5).. 54 watts of panel. I would round to 60 watts..
Rough estimate but close.. Oh, and you need a charge controller between the battery and the panel..
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Just go single rail, use solar panels that Never goes over 60v in any conditions, and have them charge a cap bank instead of batteries. Of course, it won't work in the dark, but the only item that needs replaced due to wear is the solar panels. No battery expenses whatsoever.
If your speakers don't mind too much, use one of these lower load options:
16 ohm speakers or
4 ohm resistor series to 8 ohm speaker (will cause a frequency tilt though, but you can bypass the 4R with 0.68u if you need more airy treble), or
8 ohm speakers in series, or
20 ohm speakers
The lighter load will make the amp work much more efficiently due to sending less power into both the heatsink and speaker.
If your speakers don't mind too much, use one of these lower load options:
16 ohm speakers or
4 ohm resistor series to 8 ohm speaker (will cause a frequency tilt though, but you can bypass the 4R with 0.68u if you need more airy treble), or
8 ohm speakers in series, or
20 ohm speakers
The lighter load will make the amp work much more efficiently due to sending less power into both the heatsink and speaker.
Hi OffGridKindaGuy,
Thank's for math !
I will use amp maybe two or three hours per day, that give about 3 days of listening. During 3 days, the lead acid battery will have enough time to recharge same if there is not much sun.
I'll buy the converter and experiment charge and discharge..
Yes I have a controller, it is integrated into the panel, solar panel is specific for battery.
He looks like this :
Amorphous Solar Panel — 7 Watt | Amorphous Solar Panels| Northern Tool + Equipment
Phil.
Thank's for math !
I will use amp maybe two or three hours per day, that give about 3 days of listening. During 3 days, the lead acid battery will have enough time to recharge same if there is not much sun.
I'll buy the converter and experiment charge and discharge..
Yes I have a controller, it is integrated into the panel, solar panel is specific for battery.
He looks like this :
Amorphous Solar Panel — 7 Watt | Amorphous Solar Panels| Northern Tool + Equipment
Phil.
Hi Daniel,
Sorry, I don't understand when you said " but you can bypass the 4R with 0.68u if you need more airy treble".
Outdoor speakers are 8 Ohm.
Reson to use dual rail is to try first LM with chipamp PSU, and after with batteries to compare.
I build a TDA2050 (very similar with 1875, I think) with single rail, not so good for my ears, maybe due by big cap at output ?
Generaly, I think that dual rail works better than single with same ic.
Phil.
Sorry, I don't understand when you said " but you can bypass the 4R with 0.68u if you need more airy treble".
Outdoor speakers are 8 Ohm.
Reson to use dual rail is to try first LM with chipamp PSU, and after with batteries to compare.
I build a TDA2050 (very similar with 1875, I think) with single rail, not so good for my ears, maybe due by big cap at output ?
Generaly, I think that dual rail works better than single with same ic.
Phil.
I don't understand the philosophy of using two battery systems.
Each battery loses ~30% of it's input energy.
Two battery systems in tandem will lose ~50% of the solar power. What a waste.
Take the solar power and charge up a big capacitor.
Open up the lion charger and remove the whole mains side. Feed the capacitor charge direct into the DC charger circuit and feed the DC charger direct to the efficient amplifier, not a ClassAB.
Now you have NO BATTERY losses.
Each battery loses ~30% of it's input energy.
Two battery systems in tandem will lose ~50% of the solar power. What a waste.
Take the solar power and charge up a big capacitor.
Open up the lion charger and remove the whole mains side. Feed the capacitor charge direct into the DC charger circuit and feed the DC charger direct to the efficient amplifier, not a ClassAB.
Now you have NO BATTERY losses.
There is no technical reason for single rail to work any better, nor any worse, than a dual rail.
Either you built it wrong, or you were not comparing like to like.
You must be right, but some people said that it's better with dual rail, I don't know..
About batteries, I am aware that my setup is not the better way, but I try to make it with that I have at home, to have a cheaper way.
I'll think about your advices, and other advices..
Phil.
A blocking diode is a different animal than a charge controller..
Not supplying the battery with enough current to make it bubble a little will cause it to become Stratified over time..
Water Loss, Acid Stratification and Surface Charge - Battery University
Not supplying the battery with enough current to make it bubble a little will cause it to become Stratified over time..
Water Loss, Acid Stratification and Surface Charge - Battery University
An externally hosted image should be here but it was not working when we last tested it.
I bought a converter, it's works.
At beginning voltage bat was 12,6, at end charge 12,3 volts.
So I hope charging two Li Ion without discharge completly.
Waiting a better and cheaper process
Now I can build "point to point" LM1875 .
I don't knaw what kind of problems I will discover, cause it's first time..
I have seen pictures on internet, I will inspire me.
Phil.
I use this monoblock with my 30w solar panel. No need for stereo sound when outside working. I plugin direct since the panel voltage will be around 20v with the load of the amp. The amp is a single rail TDA2050. The LM1875 will also work. These ICs have a very wide supply range that doesn't affect their stability or sound other than a lower supply rail means lower clipping headroom.
It works even when it is overcast, just reduced power. I use a 10,000uf cap on the supply because the shaded panel's source impedance will be high and cause the supply to be pulled down too much on current demands, such as the kick drum beats.
It works even when it is overcast, just reduced power. I use a 10,000uf cap on the supply because the shaded panel's source impedance will be high and cause the supply to be pulled down too much on current demands, such as the kick drum beats.
An externally hosted image should be here but it was not working when we last tested it.
That's true.
But, if I had to find an excuse of some sort, then perhaps the portion of LM1875's datasheet marked "Stability" and the associated output filter parts, may have been overlooked on that particular build.
Hi,
Looking for best way for "ground", and advice is needed..
I think add a breaker in O volt like this :
and the star ground was :
Thank's.
Phil.
Looking for best way for "ground", and advice is needed..
I think add a breaker in O volt like this :
An externally hosted image should be here but it was not working when we last tested it.
and the star ground was :
An externally hosted image should be here but it was not working when we last tested it.
Thank's.
Phil.
that looks right. OH!.
I misread your diagram.
No, it is wrong.
The input PAIR are connected as a PAIR.
Connection b allows the amplifier to "measure" the input signal.
b MUST go to a and that MUST be taken to the input signal socket.
c, d & e connect together to form the power ground.
The black line connection from the input socket to the star ground is confusing in that lower pic.
That blk wire is the signal return. IT MUST NOT be taken as a single wire.
It MUST always be paired and preferably twisted with it's partner signal hot wire from the amplifier to the signal socket.
Similarly the blk line connection from the spkr is the spkr return. It too must be paired with the spkr output signal wire. That pair MUST go from amplifier to output sockets.
If you think about EVERY signal wire and pair it with it's return wire you will find that 95% of the connections work themselves out.
The last few % are the genuine single wire references, or single wire conduits to take interference to Chassis and thence to "Earth".
I misread your diagram.
No, it is wrong.
The input PAIR are connected as a PAIR.
Connection b allows the amplifier to "measure" the input signal.
b MUST go to a and that MUST be taken to the input signal socket.
c, d & e connect together to form the power ground.
The black line connection from the input socket to the star ground is confusing in that lower pic.
That blk wire is the signal return. IT MUST NOT be taken as a single wire.
It MUST always be paired and preferably twisted with it's partner signal hot wire from the amplifier to the signal socket.
Similarly the blk line connection from the spkr is the spkr return. It too must be paired with the spkr output signal wire. That pair MUST go from amplifier to output sockets.
If you think about EVERY signal wire and pair it with it's return wire you will find that 95% of the connections work themselves out.
The last few % are the genuine single wire references, or single wire conduits to take interference to Chassis and thence to "Earth".
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Thank's John, fuse is missing at schematic, I add it :
Phil.
An externally hosted image should be here but it was not working when we last tested it.
Phil.
Summarising.
The input arrives as a pair.
The output leaves as a pair.
The power arrives as a triplet.
There are two more connections.
The output needs a reference to the input. This is usually made at the Main Audio Ground (MAG).
The Chassis to MAG. For battery operation this last may be omitted.
8 or 9 wires in total.
The input arrives as a pair.
The output leaves as a pair.
The power arrives as a triplet.
There are two more connections.
The output needs a reference to the input. This is usually made at the Main Audio Ground (MAG).
The Chassis to MAG. For battery operation this last may be omitted.
8 or 9 wires in total.
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