RV and vandwellers wiki

User Tools

Site Tools

Trace:
electrical:solar:charge_controller

Differences

This shows you the differences between two versions of the page.

Link to this comparison view

Both sides previous revision Previous revision
Next revision 		Previous revision
Next revision Both sides next revision
electrical:solar:charge_controller [2024/02/16 23:32]
frater_secessus [how to choose] added video 		electrical:solar:charge_controller [2024/06/01 21:57]
frater_secessus [specs]
Line 25: Line 25:
  
 Cautionary example:  [[https://www.youtube.com/watch?v=z5RtZe9AW2E|12W Unregulated Panel vs. 220Ah AGM Bank]] Cautionary example:  [[https://www.youtube.com/watch?v=z5RtZe9AW2E|12W Unregulated Panel vs. 220Ah AGM Bank]]
 +==== sensors ====
 +
 +To charge correctly the controller needs to know the precise voltage and temperature of the battery bank.  
 +In the best case scenario these measurements are done with an external **temp sensor** and **voltage sense**((not a typo, it's called voltage sense)) that plug into the controller or talk to the controller via bluetooth. 
 +
 +In the absence of external sensors the controller tries to use any internal sensors it might have.  The values will be inaccurate: 
 +
 +  * battery voltage will read [[electrical:12v:voltage_sag|falsely high during charging]], and
 +  * temperature will read high because of the controller's own heat from electronics
 +
 +With lead-chemistry batteries both conditions cause [[electrical:12v:psoc|chronic undercharging]], a key cause of [[electrical:batterycide|premature battery failure]].  Many LiFePO4 batteries have [[opinion:frater_secessus:agm2lifepo4#wait_lfp_can_be_damaged_by_charging_in_cold_weather|low temperature charging cutoff]] if the charger cannot disconnect when battery temps are ~freezing.
 +
 +
 +
 +
 ===== specs ===== ===== specs =====
  
Line 32: Line 47:
   * **12v/24v/48v** - this refers to the nominal voltage of the battery bank it will be charging.    * **12v/24v/48v** - this refers to the nominal voltage of the battery bank it will be charging. 
   * **Maximum input voltage** - the highest voltage the controller should //ever// see from the solar array.((it is common to leave ~20% margin))  NOTE: a 50v input max does //not// mean a PWM controller can make efficient use of mismatched panel/battery voltages; that requires MPPT.  See [[#how_to_choose|how to choose]] below.   * **Maximum input voltage** - the highest voltage the controller should //ever// see from the solar array.((it is common to leave ~20% margin))  NOTE: a 50v input max does //not// mean a PWM controller can make efficient use of mismatched panel/battery voltages; that requires MPPT.  See [[#how_to_choose|how to choose]] below.
 +  * **Minimum input voltage** - a PWM controller will requires panel voltage ≥ battery voltage to charge.  MPPT controllers will usually require a bit more voltage headroom to start/run the MPPT algorithm.((although less common, //boosting// MPPT do exist that can increase incoming voltage in order to charge a higher-voltage battery bank))
  
  
electrical/solar/charge_controller.txt · Last modified: 2024/06/01 22:01 by frater_secessus

Page Tools

Except where otherwise noted, content on this wiki is licensed under the following license: CC Attribution-Noncommercial-Share Alike 4.0 International

affilliate disclosure

CC Attribution-Noncommercial-Share Alike 4.0 International Donate Powered by PHP Valid HTML5 Valid CSS Driven by DokuWiki