SolarDesignTools provides free interactive online design tools for Electric Solar Power energy systems. This includes determining the required number of solar panels, how many batteries will be needed, calculating wire sizes, a solar radiation chart, example system pictorials, and more.
Try this example of an interactive electric Solar Power Simulator to see how Solar Energy systems work.

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Wire Size Calculator

Wire Sizing
The correct wire size for connecting solar panels to the batteries in a solar energy system must be a large enough size (gauge) to safely and efficiently carry the DC current from the solar panels to the system equipment. If the wires/cables are too small, not only can the wiring get hot (which is bad), but also there will be a voltage drop due to the resistance of the wires and less energy (amps) will be delivered to the batteries. There are two ways to solve this problem. The first is of course use larger wires/cables. Since copper wires are expensive, a better approach is to use a higher voltage system.
Instructions for the Wire Size Calculator
In order for the energy from your Solar Panels to reach your Battery Bank without serious loss of power, you will need to calculate the proper size of wires to use. Just like water in a pipe, the larger the pipe, the more water that can pass through it. Also like higher water pressure allows more water to flow, a higher system voltage allows more amps to flow from your solar panels. To use the Wire Size Calculator, just follow these 4 simple steps:
  • Select a Solar Panel output voltage of 12, 24, or 48 volts.
  • Select the total Amps that your Solar Panels will produce all together.
  • Select a distance in feet from your Solar Panels to your Battery Bank / Charge Controller.
  • Click the 'Calculate Wire Size' button to see the size wire required in AWG (American Wire Gauge).
Wire Size Calculator
Step 1 Select your Solar Panel Array's output Voltage.
Step 2 Select the maximum amperage your Solar Panel Array will produce.
Step 3 Select the Distance from the Solar Panels the system equipment in feet.
Step 4 Select 1% to 5% as the system's acceptable loss.

Home / Overview Starting Guide System Sizing Tool Battery Designer Wire Size Calculator Tips & Strategies Terms & Definitions
Solar Panels Charge Controllers Storage Batteries Inverters/Generators Meters & Monitoring Solar Radiation Wiring Diagrams

DISCLAIMER : The information and suggestions on this website are generally proven and accepted standards and techniques. They are, however, not meant to supersede local zoning laws or the recommendations of a licensed electrician. Always read the instructions provided with your equipment and observe all safety precautions.