25 is the example result. Read it using the units and relationship stated below.
Solar Charge Controller uses solar array watts, battery voltage.
Distinguishing electrical arithmetic from equipment selection
For solar charge controller, the relationship is Result = (([Solar array watts]) ÷ ([Battery voltage])). The amount depends on the supplied solar array watts, battery voltage, rather than a live market price or a value imported from another record. Power, energy, voltage and current describe different quantities. Watts represent a rate; watt-hours represent energy over time. Battery and inverter losses can reduce usable runtime even when the rated capacity is unchanged.
What the model includes
Result = (([Solar array watts]) ÷ ([Battery voltage])) Read unit labels before comparing results. Motor estimates depend on phase, efficiency and power factor; energy budgets depend on duration and duty cycle. Nameplate values and measured consumption may differ under real loads. Treat the output as the stated estimate. It does not select a code-compliant conductor, protective device or complete installation. Equipment specifications and applicable requirements remain part of the design decision.
Example with the supplied inputs
Solar array watts: 1200; Battery voltage: 48. Result: 25. The values are illustrative.
Compare one changed input
Solar array watts changes from 1200 to 1320. The result becomes 27.5. All other inputs remain fixed.
Calculation rule
Result = (([Solar array watts]) ÷ ([Battery voltage]))
Inputs and output
| Input | Example value | Entry convention |
|---|---|---|
| Solar array watts | 1200 | Measure solar array watts in the displayed unit. Convert the source measurement before entry if it uses another system; a changed label does not perform a unit conversion. |
| Battery voltage | 48 | Use the source quantity represented by battery voltage. Keep the counted population fixed and avoid mixing a unit value with a period total. |
Output: 25 is the example result. Read it using the units and relationship stated below. Use the formula to distinguish a cash amount, count, percentage or ratio.
How to use the page
Collect the inputs
Gather Solar array watts, Battery voltage. Use one period and the units shown in the form.
Run the calculation
Enter the values and select the action. The calculation rule above explains how the inputs produce the result.
Compare a scenario
Change Solar array watts on its own, keeping the other inputs fixed. Read both results before changing another assumption.
Worked example
With the example inputs listed above, the result is 25.
Change Solar array watts from 1200 to 1320 while keeping every other value fixed. The result becomes 27.5. This comparison isolates that input; it does not forecast how other variables will respond.
Check the stated formula, units and limits before using the result in a decision.
Keep the displayed formula, input units and model scope with the result. Corrections or questions can be sent through the request section on this page.
Content updated: October 11, 2026