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electrical:12v:directcharginglfp

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electrical:12v:directcharginglfp [2022/09/17 18:25]
frater_secessus [assessing your own setup for direct alternator charging] 		electrical:12v:directcharginglfp [2022/10/28 10:44]
frater_secessus [assessing your own setup for direct alternator charging] vehicle loads
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   * standard regulators (no external regulators, internal regulator hacks, etc)   * standard regulators (no external regulators, internal regulator hacks, etc)
   * with rated capacities ≥120A((where stated))   * with rated capacities ≥120A((where stated))
 +  * plain isolators, not voltage-boosting [[electrical:12v:b2b|DC-DC chargers]]
  
 Since it includes screenshots the data will be for installs documented before Sept 15, 2022.   Since it includes screenshots the data will be for installs documented before Sept 15, 2022.  
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   * you **already own a DC-DC**    * you **already own a DC-DC** 
-  * you **need consistent, predictable charging**, like 40A over the next hour.  DC-DC will provide this((barring interference from big chassis loads, BMS protections, high ambients, etc));  isolator charging starts out high and drops linearly.  You might learn its behavior over time, but it will never be as easy as "40A for 1.5 hours = 60Ah". +  * you **need consistent, predictable charging**, like 40A over the next hour.  DC-DC will provide this((barring interference from big chassis loads, BMS protections, high ambients, etc));  isolator charging starts out high and drops as battery voltage rises.  You might learn its behavior over time, but it will never be as easy as "40A for 1.5 hours = 60Ah". 
   * you **don't want to think about the battery**.  DC-DC will either stop charging (Renogy) or drop to float (all others) when charging is complete.  Isolators need to be switched off after charging, if you are driving long enough to fully charge the bank.   * you **don't want to think about the battery**.  DC-DC will either stop charging (Renogy) or drop to float (all others) when charging is complete.  Isolators need to be switched off after charging, if you are driving long enough to fully charge the bank.
   * **choosing wiring** can require some research   * **choosing wiring** can require some research
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   - Read and understand your Li battery manufacturer's charging specs - undercharging is fine((assuming one stays above 20% State of Charge)); overcharging is less so but is relatively rare in an isolator context.   - Read and understand your Li battery manufacturer's charging specs - undercharging is fine((assuming one stays above 20% State of Charge)); overcharging is less so but is relatively rare in an isolator context.
   - Read and understand your alternator's specs   - Read and understand your alternator's specs
 +  - measure how much current from the alternator your vehicle requires to run its own loads.  Since alternators can, //while driving//, run continuous current ~1/2 of their rating this means the bank can use (ALTERNATOR RATING / 2) - VEHICLE LOADS.  If your bank wants to pull more than that an appropriately-sized DC-DC may be required. 
   - Read and understand your isolator's specs and functionality   - Read and understand your isolator's specs and functionality
   - observe your vehicle's chassis voltage during normal operation - note that the voltage //at the battery's location// will likely be lower due to long wiring and also lower when the wiring is carrying a hefty charging current.     - observe your vehicle's chassis voltage during normal operation - note that the voltage //at the battery's location// will likely be lower due to long wiring and also lower when the wiring is carrying a hefty charging current.  
electrical/12v/directcharginglfp.txt · Last modified: 2024/06/20 18:12 by frater_secessus

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