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--- lifestyle:faq_solar_generator [2024/05/12 14:07]
frater_secessus [solar input]
+++ lifestyle:faq_solar_generator [2024/08/04 22:08] (current)
frater_secessus [solar input]
@@ Line 103: / Line 103: @@
 === solar charging limits ===
+also see [[12v:sg_troubleshooting#must_i_use_the_ps_brand_s_proprietary_solar_panels|this article]] on choosing panels for a SG
 Many smaller units have quite restrictive solar input limits.
-  * **voltage** - 24Voc is a common voltage limit, effectively limiting one to [[electrical:solar:panels#panel_voltage|12v nominal]] panels. **Input voltage limits must not be exceeded**.
+  * **voltage** - 24Voc is a common voltage limit, effectively limiting one to [[electrical:solar:panels#panel_voltage|12v nominal]] panels. **Input voltage limits must not be exceeded**.  Note:  some very large units have high input //minimums//, like 50v.
   * **current** limit - 3A is a common input current limit on smaller, less-expensive units.  8A is a common limit on larger units.
-    * With PWM controllers the max power harvestable will be 3A x [internal battery voltage], which can be as low as 9v.  9v x 3A 27w.  **Input current limits must not be exceeded**
+    * With PWM controllers the max power harvestable will be 3A x [internal battery voltage], which can be as low as 9v.  9v x 3A 27w.  **PWM input current limits must not be exceeded**
-    * MPPT controllers with the same limit might run the panels at 18v, the Vmp:  18v x 3A = 54w((minus DC-DC conversion losses of ~5%))  With MPPT the current limit can usually be exceeded somewhat by panels and the controller will throttle back incoming current to hold the limit. The allowqable amount of overpanel is is [[electrical:solar:overpaneling#vs_charge_controller|well-documented with standalone MPPT controllers]] but "power stations" are usually black boxes with no published overpanel spec.  Proceed at your own peril.
+    * MPPT controllers with the same limit might run the panels at 18v, the Vmp:  18v x 3A = 54w((minus DC-DC conversion losses of ~5%))  MPPT  incoming current limits can usually be exceeded; the controller will throttle back incoming current to hold the limit. The allowable amount of overpanel is [[electrical:solar:overpaneling#vs_charge_controller|well-documented with most standalone MPPT controllers]] but "power stations" are usually black boxes with no published overpanel spec.  Proceed at your own peril.
 == the Amp bottleneck ==
-Because the Amp limit is usually the limiting factor for power production, selecting a panel with a Voc((//not// Vmp)) closer to the unit's input limit((with some headroom)) will make maximal power given the limitations.  This is because for a given rated output like 100w a higher Vmp (volts) means a lower Imp (amps).
+Because the Amp limit is usually the limiting factor for MPPT power production.  Selecting a panel with a Voc((//not// Vmp)) closer to the unit's input limit((with some headroom)) can make maximal power given the limitations.  This is because for a given rated output like 100w a higher Vmp (volts) means a lower Imp (amps).
   * 22.5Voc panel - Vmp ~18v.((Vmp is typically 0.8 of Voc)) 18v x 8A limit = **144w**.

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