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electrical:12v:alternator

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electrical:12v:alternator [2024/04/26 16:59]
frater_secessus [heat] 		electrical:12v:alternator [2024/05/09 14:00] (current)
frater_secessus [isolator without a house battery]
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   - use [[electrical:12v:b2b|a DC-DC charger]] to get at least the correct charging voltage   - use [[electrical:12v:b2b|a DC-DC charger]] to get at least the correct charging voltage
   - if charging by relay only, use Crtical size wire to get the most voltage and current to the lead house battery   - if charging by relay only, use Crtical size wire to get the most voltage and current to the lead house battery
 +
 +==== triggering  ====
 +
 +The setup needs to be //triggered// (told when to start/stop) so that it isn't connected all the time.  There are two main methods:
 +
 +  - use of an ON/OFF 12v trigger signal ("D+", "IGN", "ACC").  When the 12v signal is present the charging circuit is operational.  Caveat:  in this kind of setup leaving the key in the ACC position without starting the engine can drain the starter battery. 
 +  - voltage-sensing - 12v is always being provided to the charger.  The batteries are connected when the chassis voltage is above a voltage setpoint (often ≥13.4v) and disconnected when the chassis side measures below  a setpoing (often ≤13.2v).  
 +
 +In some cases both are combined for particular installs.  Ex.  smart alternators. 
 +
 +
 +
  
 ===== alternator hacks ===== ===== alternator hacks =====
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 ==== workaround: heavier wiring ==== ==== workaround: heavier wiring ====
  
-It's also possible to run a separate and heavier cable from the TV to the trailer;  this would minimize voltage sag.  If a plain isolator is used with heavier wiring the voltage will still be insufficient to fully charge lead batteries.    +It's also possible to run a separate and (much) heavier & more expensive cable/connector from the TV to the trailer;  this would minimize voltage sag.   
 + 
  
-Heavier cabling + a DC-DC charger could provide correct voltage to the trailer battery.  
  
 ===== isolator without a house battery ===== ===== isolator without a house battery =====
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-This setup would be:  starter battery -> isolator -> inverter -> 120vac devices+This setup would be:  starter battery -> combiner((A $25-$40 VSR (often marketed as a smart battery isolator) might be easiest. Could go even cheaper with a regular relay but you'd have to hunt for a D+/IGN signal.))   
 + -> inverter -> 120vac devices 
 + 
  
  
electrical/12v/alternator.1714165141.txt.gz · Last modified: 2024/04/26 16:59 by frater_secessus

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