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Catalogue · 7 products

Solar Charge Controllers

Charge controllers for 12 V and 24 V battery banks, in both types: PWM at 20 A and 30 A for small arrays, and MPPT at 20 A, 40 A and 60 A for anything larger.

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The controller sits between the panels and the battery and stops the battery being overcharged. PWM is the simple, low-cost type and is fine for a panel or two of 12 V nominal type. MPPT converts surplus panel voltage into extra charging current, which is worth 20 to 30 percent more harvest and lets you use higher-voltage panels and longer cable runs.

Choose by the array's current at your battery voltage with 25 percent headroom, and check the array's open-circuit voltage against the controller's input limit. Each listing gives both figures, and both types are set up for LiFePO4 charging.

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Solar Charge Controllers
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MPPT or PWM: choose a charge controller

ControllerBest forConfirm before ordering
MPPTLarger arrays, panels wired in series, and residential-style panels on a 12V/24V/48V batteryMaximum PV input voltage (Voc) in cold weather, and output current at your battery voltage
PWMSmall systems where the panel voltage is matched to the battery (for example, a 12V panel on a 12V battery)Panel nominal voltage matches battery voltage; array current is below the controller rating

Rough current sizing: array watts ÷ battery voltage = charge amps (for example, 800W ÷ 12V ≈ 67A, so an 80A MPPT controller). Panel open-circuit voltage rises in cold weather, so keep the series string's cold-weather Voc below the controller's maximum PV input.

Not included unless listed

  • Solar panels, batteries and mounting
  • PV and battery cables, fuses and breakers
  • Temperature sensor or remote display, unless listed
Can I use residential (60/72/108-cell) panels with a PWM controller?

Not efficiently. Their voltage is much higher than a 12V battery. Use an MPPT controller.

Does the controller work with lithium batteries?

Check that it has a LiFePO4 or user-defined charging profile, and set it to the voltages in the battery datasheet.

MPPT controllers · PWM controllers · Solar panels · LiFePO4 batteries

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