HomeGlossary › Solar charge controller (MPPT)

What is an MPPT charge controller?

Converts the panels’ variable voltage into the right charging voltage for your battery, squeezing the most energy out of the array. MPPT is the tracking method it uses.

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Why it matters

Panels and batteries want different voltages. An MPPT controller bridges them and squeezes the most energy out of the array — typically 20-30% more than a cheap PWM controller in real conditions.

Where it fits in your system

It sits between the solar array (via the isolator) and the battery or charge busbar, converting the panels’ variable voltage into a correct charging voltage.

How Wattonomy handles it

Design your van, boat, cabin or RV system in Wattonomy and it sizes the MPPT to your array and battery voltage and shows its fusing and cable on both sides — from the appliances you actually run, sized to the recognized standard for your region. You see it on the wiring diagram, in the sized parts list, and in a plain-English build pack that explains the reasoning behind every choice. No account, no email — about a minute to a complete, validated design.

Questions

What does MPPT stand for?

Maximum Power Point Tracking — the method the controller uses to continuously find the voltage at which your panels deliver the most power.

MPPT or PWM — which do I need?

For lithium and most modern arrays, MPPT. It harvests more energy and handles higher array voltages; PWM only makes sense on the smallest, voltage-matched setups.

Design your system — free

It takes about a minute. No account, no email.