What is a "solar string"?

　　PV Array, Individual PV Modules are connected in both Series and Parallel. A Series Connected Set of Solar Cells or Modules is Called a "String".

　　Series String Example

　　Parallel String Example

　　What size or circuit breaker for a solar Panel String?

　　To determine the normal fuse size use this equation:

　　String Circuit Ampacity = Short Circuit Current (ISC) x 1.56 = Fuse SIZE.

　　Example:

　　String Short Circuit Current 8.73 AMPS (ISC) x 1.56 = 13.62 AMPS. Fuses Are Rated in Standard Sizes of 6, 8, 10, 10, 20, 25 OR 30 AMPS. The nec States that you muststedAbove the ampages value. For 13.62 amps, you would use a 15 amp fuse or circuit breaker.

　　Things to remember when sizing your solar combiner box.

　　1. The Current Passing Through the String Will Stay the Same As One Panel Regardless of the Number of Panels in the String.

　　2. The Voltage Increases with Each Panel You Add. The Voltage Will be the Sum of All the Panels Connect in Series.

　　1. The Current Passing Through the String Will Increase with Each Panel Added. Your Total Current Will Be the Sum of All the Panels in the String.