Solar notes

Migration

Assumes 5 solar hours per day at 20° latitude

Panel options:

• <1W RAK IP66 case
  
• 3W RAK case, flex panel
  
• 6W Flex usb and  soshine 6V panel
  
• 40W flex panel

Case options:

• RAK prebuilt case (3W or 1W)
  
• IP66 plastic case
  
• screw on j-box (not recommended, except where tampering is possible)

Issues:

• Regulated power is critical
  
• Solar charge controller on RAK19007 can be overloaded (5.5V max)
  
• USB charging on ESP32 devices works most of the time, if regulated
  
• If USB charging is not regulated, will cause reboots
  
• If RAK solar charging is not regulated, unit burns out
  
• Cooling of CPU unit is important, build under panel where possible
  
• antenna connections must be sealed, and preferably not on the top
  
• N type antenna mounts tend to flex, breaking the seal, allowing water entry
  

Antennas:

• dipole stick is best
  
• N type 9 dB is strongest
  
• stubby is minimally effective, but good for stealth

Batteries:

• Lipo with charge protection:
  
• 1100mAh is minimal
  
• 3000mAh is basic
  
• 8000mAh is extreme

Using 18650 batteries is great, but they need a charging module like the waveshare charging module, 9900 mAh max so far

Rates:

• At 5 solar hours, 6W panel is 30Wh
  
• A 3000mAH 3.7V battery is 11 Wh
  
• A 9900mAh 3.7V battery is 36Wh
  
• So…
  
• a single 3000mAh battery can be charged by a 2W panel
  
• a single 9900mAh battery can b charged by a 6W panel
  
• A 40W panel will charge a 50Ah battery at 3.7V
  
• A 40W panel at 5 hours per day is 200Wh, at 12V this is 16Ah battery
• To run overnight, loads are needed, average for RAK 19007 is about 1 mA
  
• 20 hours of non-solar means 20 mAh, more if GPS is activated
  
• More if the unit is a repeater or router, less if in progressclient formute mode
  
• ESP32 models use more, about 60mA with bursts, higher if wifi is enabled (120 mA)
  

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Migrated from Apple WikiServer Wiki. Original page v87853S.ID: v87853S