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Charging from multiple sources

If an inverter draws current from the battery while it is charging, does it affect the charger in any way? Say a 20A charger is charging a 12V battery and the inverter draws 50A. Is the load spread across the charger and the battery? Can an inverter damage the charger by drawing current out of it?
 
Shouldn't cause damage to charge controller.

A charge controller delivers amps, into a battery of some voltage. The voltage of battery varies with current (charging or discharging) and state of charge.
Inverter draws current from battery, pulling its voltage a bit lower.

Charge controller won't deliver more than its maximum output current. It may deliver less when transitions to constant voltage mode, and battery accepts less current.
If inverter then draws current, charge controller would deliver more, up to its limit.

Voltage and current changes might make charge controller transition to a different mode (go to float, etc.) prematurely.
Lead-acid battery would prefer a particular current, and inverter steals some of that.

Some charge controllers (Victron, Midnight) can work with a shunt and regulate battery charge current to desired amount, while delivering more current when inverter draws it.
Hybrids with built in charge controller and inverter should also do that.

A charger/inverter could also deliver current to battery from grid/generator. With shunt or lithium BMS communication, it can be aware of charge controller current so it adjusts its current accordingly.
 
If an inverter draws current from the battery while it is charging, does it affect the charger in any way? Say a 20A charger is charging a 12V battery and the inverter draws 50A. Is the load spread across the charger and the battery? Can an inverter damage the charger by drawing current out of it?
Yes it affects the charger by drawing load from it first. In your example of a 50a load the charger would supply 20a and the battery would make up the 30a remaining. No it will not damage the charger.
 
One can have as many independent charging sources running concurrently as they like provided they are programmed properly for the voltage of one's battery bank.

Examples (some or all at once, even multiples of a single type, different brands, etc.):
  1. Solar PV via MPPT
  2. Solar PV via PWM
  3. AC-DC input via MPPT (using a AC to DC power supply feeding an MPPT solar controller with voltage/current consistent with a solar panel)
  4. Wind with suitable controller
  5. Grid/Generator AC via inverter/charger
  6. Grid/Generator AC via RV AC-DC converter
  7. Hydro with suitable controller
  8. Anything else someone might use to charge an off-grid energy storage system.
This is true for any battery chemistry.

Again, important that all chargers are appropriately configured to handle the battery bank with suitable absorption and float voltages.

Also very important that the sum of all charge currents do not exceed the recommended max charge current of the battery bank.


Note:
Multiple chargers only offer benefit when the battery is below the absorption voltage. Once the absorption voltage is hit, it is now a voltage limited charge and thus current will be lower than the sum of all sources. The battery bank will only accept as much current as it needs to maintain the absorption voltage. As the battery bank fills, current is reduced and chargers can no longer deliver current at the absorption voltage. They will drop out and go to float. Typically, the highest current charging source will always be the last source charging while all others are at 0A and likely in float mode.

Comments and corrections are welcome.
The amp of each source will double the total amp charging, right? Let's say chargecontroller1 is set to 50a and the other chargecontroller2 at 50a will be 100a.
Trying to understand your statement:
Also very important that the sum of all charge currents do not exceed the recommended max charge current of the battery bank.
 
The amp of each source will double the total amp charging, right?

No. The use of "double" is incorrect. Sources sum, but only in bulk phase.

Let's say chargecontroller1 is set to 50a and the other chargecontroller2 at 50a will be 100a.

Yep.

Trying to understand your statement:
Also very important that the sum of all charge currents do not exceed the recommended max charge current of the battery bank.

If your batteries are rated for 200A charging, the sum of all charge sources must be less than 200A.
 
I still miss Snoobler. I liked him.
I don't like this "Happy, Everything is Sunshine!" guy.
He ought to be living under a cloud all the time, like the rest of us.

I guess not. I knew your secret identity, but I didn't know it wasn't a secret. ;)

I'm not sure why, but I did have the impression we were dealing with Dr. Jekyll and Mr. Hyde.
Maybe because people can be recognized by their writing?
I guess leaving a forwarding and return address seals it. (be careful what you write on envelopes for anonymous letters, and where they are postmarked.)
 
One can have as many independent charging sources running concurrently as they like provided they are programmed properly for the voltage of one's battery bank.

Examples (some or all at once, even multiples of a single type, different brands, etc.):
  1. Solar PV via MPPT
  2. Solar PV via PWM
  3. AC-DC input via MPPT (using a AC to DC power supply feeding an MPPT solar controller with voltage/current consistent with a solar panel)
  4. Wind with suitable controller
  5. Grid/Generator AC via inverter/charger
  6. Grid/Generator AC via RV AC-DC converter
  7. Hydro with suitable controller
  8. Anything else someone might use to charge an off-grid energy storage system.
This is true for any battery chemistry.

Again, important that all chargers are appropriately configured to handle the battery bank with suitable absorption and float voltages.

Also very important that the sum of all charge currents do not exceed the recommended max charge current of the battery bank.


Note:
Multiple chargers only offer benefit when the battery is below the absorption voltage. Once the absorption voltage is hit, it is now a voltage limited charge and thus current will be lower than the sum of all sources. The battery bank will only accept as much current as it needs to maintain the absorption voltage. As the battery bank fills, current is reduced and chargers can no longer deliver current at the absorption voltage. They will drop out and go to float. Typically, the highest current charging source will always be the last source charging while all others are at 0A and likely in float mode.

Comments and corrections are welcome.
I agree, but am still hesitant to connect a separate charge controller to the battery packs bus bars as they are connected to two other inverter/charge controllers. See pic. below. I would connect a charge controller from separate panels, which would be ok right?!?IMG_0671.jpeg
 
Yes, you would connect the controllers output to the bus bars. The whole job of a bus bar is to give you an easy spot to bring your wires together without needing a wire nut the size of your head.

The charge controllers won't care about anything else connected other than "I have a battery, I will charge it."
 
One can have as many independent charging sources running concurrently as they like provided they are programmed properly for the voltage of one's battery bank.

Examples (some or all at once, even multiples of a single type, different brands, etc.):
  1. Solar PV via MPPT
  2. Solar PV via PWM
  3. AC-DC input via MPPT (using a AC to DC power supply feeding an MPPT solar controller with voltage/current consistent with a solar panel)
  4. Wind with suitable controller
  5. Grid/Generator AC via inverter/charger
  6. Grid/Generator AC via RV AC-DC converter
  7. Hydro with suitable controller
  8. Anything else someone might use to charge an off-grid energy storage system.
This is true for any battery chemistry.

Again, important that all chargers are appropriately configured to handle the battery bank with suitable absorption and float voltages.

Also very important that the sum of all charge currents do not exceed the recommended max charge current of the battery bank.


Note:
Multiple chargers only offer benefit when the battery is below the absorption voltage. Once the absorption voltage is hit, it is now a voltage limited charge and thus current will be lower than the sum of all sources. The battery bank will only accept as much current as it needs to maintain the absorption voltage. As the battery bank fills, current is reduced and chargers can no longer deliver current at the absorption voltage. They will drop out and go to float. Typically, the highest current charging source will always be the last source charging while all others are at 0A and likely in float mode.

Comments and corrections are welcome.

Yes, you would connect the controllers output to the bus bars. The whole job of a bus bar is to give you an easy spot to bring your wires together without needing a wire nut the size of your head.

The charge controllers won't care about anything else connected other than "I have a battery, I will charge it.
Great thanks, I appreciate it!
 
How can I charge my Lithium battery using the cigarette charger in my vehicle?
PL. Pp


I have an MPP Solar all in one unit with 600 watts of solar panels and a 24v lithium battery....but often when traveling on cloudy days my battery is not fully charged when I arrive at my destination 10 hours later and the sun is already down for the night.
Not your best option. Because your cigarette charger is probably 12v, your only option is a plug in boost converter capable of dealing with your battery's needs. Keep in mind whatever you get, you're still limited by the lighter's fuse rating, and the engine will need to burn a lot of gas for a little power.
 
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One can have as many independent charging sources running concurrently as they like provided they are programmed properly for the voltage of one's battery bank.

Examples (some or all at once, even multiples of a single type, different brands, etc.):
  1. Solar PV via MPPT
  2. Solar PV via PWM
  3. AC-DC input via MPPT (using a AC to DC power supply feeding an MPPT solar controller with voltage/current consistent with a solar panel)
  4. Wind with suitable controller
  5. Grid/Generator AC via inverter/charger
  6. Grid/Generator AC via RV AC-DC converter
  7. Hydro with suitable controller
  8. Anything else someone might use to charge an off-grid energy storage system.
This is true for any battery chemistry.

Again, important that all chargers are appropriately configured to handle the battery bank with suitable absorption and float voltages.

Also very important that the sum of all charge currents do not exceed the recommended max charge current of the battery bank.


Note:
Multiple chargers only offer benefit when the battery is below the absorption voltage. Once the absorption voltage is hit, it is now a voltage limited charge and thus current will be lower than the sum of all sources. The battery bank will only accept as much current as it needs to maintain the absorption voltage. As the battery bank fills, current is reduced and chargers can no longer deliver current at the absorption voltage. They will drop out and go to float. Typically, the highest current charging source will always be the last source charging while all others are at 0A and likely in float mode.

Comments and corrections are welcome.
Thank you snoobler, I totally understand. Yeh the charger that I have now (shown in the link I provided) does automatically drop the charge amperage the closer I get to the absorption stage being complete. The battery I have is a 300ah Lifepo4 that I use in my RV and sometimes I can run it down to 80ah and I have to leave my generator on for 4.5 hours to get it back up to at least 275ah and I wanted to shorten that time. Thanks again!
 
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