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electrical:solar:synopsis_puzzle2 [2017/08/01 15:10]
frater_secessus [converters]
electrical:solar:synopsis_puzzle2 [2018/02/10 11:11] (current)
frater_secessus [Synopsis: HandyBob's RV Battery Charging Puzzle]
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 +This page aims to distill the knowledge contained in HandyBob'​s [[https://​handybobsolar.wordpress.com/​the-rv-battery-charging-puzzle-2/​|RV battery charging puzzle 2]] page. 
  
 +Particularly useful and pithy statements are quoted directly under fair use.
  
-This page aims to distill the knowledge contained in HandyBob'​s [[https://​handybobsolar.wordpress.com/​the-rv-battery-charging-puzzle-2/​|RV battery charging puzzle 2]] page. 
- 
-Particularly useful and pithy statements are quoted directly. 
  
 ====== Synopsis: HandyBob'​s RV Battery Charging Puzzle ====== ====== Synopsis: HandyBob'​s RV Battery Charging Puzzle ======
  
 +[Note from Secessus: ​ I do my best here to faithfuly summarize //​Bob'​s//​ point of view and not editorialize or take issue with it.] 
  
 HandyBob and his wife are fulltimers in a 5th wheel and have no generator. ​ He prefers quiet and and wants folks to stop using generators, or at least use them more considerately. HandyBob and his wife are fulltimers in a 5th wheel and have no generator. ​ He prefers quiet and and wants folks to stop using generators, or at least use them more considerately.
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 "​Professional"​ installers may not be any good.  "​Professional"​ installers may not be any good. 
  
-On sizing:  ​ 
  
-> "If you want to just be able to run your lights, water pump, charge ​the cell phone and run the occasional small kitchen appliance, acting more like a camper than a full timer, you only need one panel and one or two batteries. ​ If you want to run the TV a bit, computer, the microwave to warm up soup or make popcorn and some kitchen appliances you’ll need two panels and four batteries. ​ Of course you need more panels if you go where the sun doesn’t shine or if want to run more, such as unusual loads like a freezer in the basement or a CPAP machine to keep you breathing all night."​ -- HandyBob+===== charge ​controllers =====
  
 +Get an oversized [[electrical:​solar:​charge_controller|3-stage charge controller]] with an equalization function.
 +
 +Bob prefers Morningstar.
 +
 +===== MPPT boost controllers =====
 +
 +They work but the gains are found in specific scenarios like deeply discharged batteries. ​ The gains are more likely to be 5%-10% over PWM.
 +
 +
 +===== wiring =====
 +
 +"Big wire" is cheaper than panels for a similar gain in power.
 +
 +Wiring from panels to controller is important; ​ wiring from the controller to batteries is critical.
 +
 +Use stranded wire, the type (building, automotive, welding) is less important. ​ Use UV-shielded wire for external runs.
 +
 +> "big wire is there to limit voltage drop, not to carry amps." -- HandyBob
 +
 +
 +===== inverters =====
 +
 +Use a properly sized [[electrical:​inverter|inverter]] for the job;  this may mean owning more than one inverter.
 +
 +MSW is fine unless you know you have something that needs PSW:  "​residential refrigerators,​ washing machines, some air purifiers, some desk top computers and Craftsman brand battery chargers."​
 +
 +"Soft start" inverters work work well.
 +
 +Many inverters have a high voltage disconnect (Vhvd) of 15v.  Temperature compensated charge controllers can hit 15v easily.
 +
 +===== installation considerations =====
 +
 +Install the charge controller near the batteries.
 +
 +Locate solar panels so they are not shaded.
 +
 +===== fusing =====
 +
 +Bob prefers fuses to automotive-style circuit breakers.
 +
 +Avoid fuse holders with springs in them.
 +
 +Fuse every positive wire within a few inches of the battery.
  
-===== charge controllers ===== 
  
  
electrical/solar/synopsis_puzzle2.1501625427.txt.gz · Last modified: 2017/08/01 15:10 by frater_secessus