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12v:sg_troubleshooting

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12v:sg_troubleshooting [2024/12/10 19:41]
frater_secessus [maxxing out the solar input] added dc-dc 		12v:sg_troubleshooting [2024/12/14 11:13] (current)
frater_secessus [maxxing out the solar input] link to new b2b section
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 This tells us that Vmp can be anywhere from 15v to 38v.  Outside that range (but within the absolute limits above) the panels will make //something// but not maximum power. This tells us that Vmp can be anywhere from 15v to 38v.  Outside that range (but within the absolute limits above) the panels will make //something// but not maximum power.
  
-==== maxxing out the DC input ====+==== maxxing out the solar input ==== 
 + 
 +[note:  the overall logic also applies to alternator charging input inputs - see also [[electrical:12v:b2b#examples_-_power_stations|this subarticle on DC-DC for power stations]].]
  
 Power station solar input docs give a Max Wattage spec with a voltage range and usually a current limit.  In the case of our example that limit is ''10A''. Power station solar input docs give a Max Wattage spec with a voltage range and usually a current limit.  In the case of our example that limit is ''10A''.
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   * 36Vmp x 10A = 360w   * 36Vmp x 10A = 360w
   * 40Vmp x 10A = 400w   * 40Vmp x 10A = 400w
- 
-[[https://amzn.to/3ZsgPYd|{{ https://m.media-amazon.com/images/I/61JNM0C6vyL._AC_UL320_.jpg?125}}]] 
-The same logic applies to 12v input from the ciggy port or alternator, hence products like [[https://amzn.to/3ZsgPYd|Bluetti's DC-DC charger]], or [[https://amzn.to/3Zv1VjR|Ecoflow's DC-DC charger]]. 
- 
  
  
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 ===== my PS doesn't charge well from the 12v ciggy port ===== ===== my PS doesn't charge well from the 12v ciggy port =====
  
-  - bad connection - [[electrical:12v:ports#the_cigarette_outlet|12v ciggy ports]] are substandard even on their best behavior.   +The basic issue is the power station is throttling input to 10A avoid popping the ciggy port's  ~10A fuse.  Since volts x amps = watts, **limiting the amps limits the watts**.   
-  - the chassis voltage is varying, so the 12v volt outlet voltage is varying, so the charge rate is varying (I=V/R) + 
-  - the power station is throttling charge rate+The approach to [[12v:sg_troubleshooting#maxxing_out_the_solar_input|maxxing solar input]] described above [[https://amzn.to/3ZsgPYd|{{ https://m.media-amazon.com/images/I/61JNM0C6vyL._AC_UL320_.jpg?125}}]] 
 +also applies to DC input from the ciggy port or alternator.((sometimes they share the same port)) Hence products like [[https://amzn.to/3ZsgPYd|Bluetti's DC-DC charger]], or [[https://amzn.to/3Zv1VjR|Ecoflow's DC-DC charger]].   
 + 
 + 
  
 > and if theres a way to have it always charge at 100w? > and if theres a way to have it always charge at 100w?
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-If the wall charger output is 100w you could even run a cheap inverter from the ciggy port and plug the wall charger into that.  It would be inefficient but we don't really care because the numbers are small and alternator output relative massive.  This approach would work because the wall charger's output is usually at the higher end of the SG's DC input voltage limit. +If the wall charger output is 100w you could even run a cheap inverter from the ciggy port and plug the wall charger into that.  It would be inefficient but we don't really care because the numbers are small and alternator output relative massive.  This approach would work because the wall charger's output is usually at the higher end of the PS's DC input voltage limit. 
  
 If the wall charger >100w((>100w wall charger + inverter losses could exceed the ciggy port's output limit, typically 10A.)) you could get more consistent charging by boosting/regulating voltage up as described above.  So if the wall charger runs at 15v one might boost the outlet's voltage to 15v.   If the wall charger >100w((>100w wall charger + inverter losses could exceed the ciggy port's output limit, typically 10A.)) you could get more consistent charging by boosting/regulating voltage up as described above.  So if the wall charger runs at 15v one might boost the outlet's voltage to 15v.  
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-===== Can I charge my SG with a regular DC-DC charger? =====+===== Can I charge my PS with a regular DC-DC charger? =====
  
 Maybe.  There are several factors involved: Maybe.  There are several factors involved:
  
-  - some [[electrical:12v:b2b|DC-DC chargers]] need to see the target battery's voltage before charging will start.  These are often called "smart" chargers.  If the DC-DC needs to see the voltage before charging but the SG does not expose that voltage to the DC charging //input// then the charger will not start.  +  - some [[electrical:12v:b2b|DC-DC chargers]] need to see the target battery's voltage before charging will start.  These are often called "smart" chargers.  If the DC-DC needs to see the voltage before charging but the PS does not expose that voltage to the DC charging //input// then the charger will not start.  
   - if the above condition is met, then the DC-DC's voltage output needs to be within the PS's voltage input range. If the input requires ≥20v then it will not charge from a nominal 12v DC-DC charger.   - if the above condition is met, then the DC-DC's voltage output needs to be within the PS's voltage input range. If the input requires ≥20v then it will not charge from a nominal 12v DC-DC charger.
   - if the above conditions are met the PS input current may still be quite limited.   See the [[#maxxing_out_the_solar_input|maxxing]] section to get the most from the charging run.    - if the above conditions are met the PS input current may still be quite limited.   See the [[#maxxing_out_the_solar_input|maxxing]] section to get the most from the charging run. 
12v/sg_troubleshooting.1733877674.txt.gz · Last modified: 2024/12/10 19:41 by frater_secessus

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