PV String Calculator
Calculate the compatibility of your photovoltaic (PV) panel configuration with AERL CoolMax SRX and SRX-R solar charge controllers
Enter Your Solar PV Configuration
1Select Controller Model
2PV Panel Specifications
3Array Configuration
Number of panels connected in series in each string
Number of parallel strings in the array
Used to calculate cold-temperature voltage rise
Ready to Calculate
Enter your PV panel specifications and configuration, then click the Calculate button to check compatibility with your selected AERL controller.
Our calculator helps ensure safe and efficient solar system design for AERL's CoolMax SRX and SRX-R controllers.
PV string design
Understand your string calculation
Use the module manufacturer’s datasheet for open-circuit voltage (Voc), maximum-power voltage (Vmp), short-circuit current (Isc), operating current (Imp) and the Voc temperature coefficient in %/°C. Enter the design minimum temperature for your site.
Modules in series add voltage. Identical strings connected in parallel add current. Cold conditions raise Voc when the temperature coefficient is negative, so the cold-corrected string voltage must stay below the controller’s maximum input voltage.
The calculator checks cold Voc, Vmp at the entered module rating, array Isc and array power against the selected controller. It does not temperature-correct Vmp or verify every installation constraint, including operating-current limits, cable sizing and protection. Use the applicable manual and have the final design checked by a qualified designer.
Worked example: 12 modules in one string
Using the calculator’s illustrative defaults: Voc 40.5 V, Vmp 33.2 V, Isc 10.2 A, Imp 9.6 A, coefficient −0.29%/°C and minimum temperature 0°C.
- String Voc at 25°C
- 12 × 40.5 = 486 V
- Cold-corrected Voc at 0°C
- 486 × [1 + (−0.0029 × (0 − 25))] = 521.2 V
- String Vmp and array power at the entered rating
- 12 × 33.2 = 398.4 V; 398.4 × 9.6 = 3,824.6 W
- Array short-circuit current
- One parallel string × 10.2 = 10.2 A
These values illustrate the calculation; replace them with your actual module and site data. A passing result is a preliminary check, not installation approval.