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Voltage - the electrical pressure that pushes current through a circuit. Common solar system voltages are 12V, 24V, and 48V.
Power - the rate of energy transfer. In solar systems, this is how much energy your panels produce or your devices consume.
Amps result
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Enter volts and watts to see the amps result.
Understanding the Relationship
Key formulas
The relationship between watts, volts, and amps follows the Power Formula:
Power (P) = Voltage (V) × Current (I)
Voltage (V) = Power (P) ÷ Current (I)
Current (I) = Power (P) ÷ Voltage (V)
In Solar Systems
Understanding these relationships helps you:
- Understand current — Higher power at the same voltage means more amps
- Choose inverters — Match wattage to your needs
- Configure battery banks — 12V, 24V, or 48V systems affect current flow
- Calculate loads — Know how much power your devices draw
Real-world solar examples
350W Panel Operating Current
A 350W solar panel at 37V Vmp produces 9.46A. This current value is the panel's operating current at maximum power.
5,000W Inverter DC Current
A 5,000W inverter on a 48V battery bank draws 104.17A at full load.
DC vs AC Current Comparison
A 240W refrigerator on a 120V AC circuit draws 2A. But on the DC side of a 12V system, the same 240W draws 20A — ten times more current.
When you'll need this conversion
- Battery-to-Inverter Current — A 3,600W inverter on a 24V system draws 150A from the battery bank. Converting inverter watts to DC amps shows how much current the battery side carries.
- Sizing a Charge Controller — With 1,800W of solar on a 24V battery system, you get 75A of charging current. You would need an 80A or 100A MPPT controller — or split the array across two smaller controllers.
DC-Side Current Is Much Higher Than AC: A 1,500W load is only 12.5A at 120V AC, but 125A at 12V DC. Do not carry an AC amp figure over to the DC side.
Isc Is Higher Than Imp: Isc is 5–10% higher than Imp and represents the maximum possible panel current.
MPPT Controllers Change the Current Ratio: An MPPT controller takes high-voltage, low-current input and converts it to low-voltage, high-current output. If your array outputs 10A at 74V, the controller might output ~15A at 48V. Always calculate amps on both sides.
Related conversion calculators
Last updated: January 3, 2026
