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MrWizard's avatar
MrWizard
Moderator
Jun 24, 2015

why don't Solar controller mfg/sellers use honest ratings

example most 30amp controllers are listed at 390w of panels and 40amp controllers at 500w of panels but we don't charge batteries at 12.0v we charge at 14v or higher 14v*30 amps 420w output, ...
MrWizard's avatar
MrWizard
Moderator
Jun 25, 2015
here is one example of what i'm saying

WindyNation P30L LCD PWM 30A Solar Panel Regulator Charge Controller 12V 24V 390W 780W + Digital Display +User Adjustable Settings for Off Grid Battery Charging


windy nation 30amp

here is another

Nominal System Voltage: 12V/24V Auto recognition
Max. PV Input Power: 400W (12V), 800W (24V)
Rated Charge Current: 30A
Max. Solar Input Voltage: 42V
Rated Load Current: 30A

Renogy 30amp controller

now this one EPsolar lists only charge amps
and does not apply a limiting panel wattage

EPsolar 30amp charge controller

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