27. Calculations MODULE INFORMATION STC VOC = 36.90 V ISC = 8.91 A Ptolerance= +5/-3% Max fuse rating = 15 A PMAX = 245 W VPMAX = 29.8 V IPMAX = 8.23 A ARRAY INFORMATION Number of modules in series = 5 Total Watts = 1225 W OPERATING VOLTAGE VPMAX = 29.8 V Number of modules in series = 5 29.8 V VPMAX x 5 = 149 Volts OPERATING CURRENT IPMAX = 8.23 A MAXIMUM SYSTEM VOLTAGE Module Voc = 36.9 VNumber of Modules in series = 5 Lowest temp. on record = -21.7°C (Coefficient of 1.25 from NEC 690.7) Maximum System Voltage 36.9 V x 5 x 1.25 = 230.63 Volts < 600 Volts MAX PV SOURCE CIRCUIT CURRENT ISC = 8.91 A 8.91 A x 1.25 = 11.4 A 8.91 A x 1.56 = 13.9 A
28. Calculations VOLTAGE DROP Vdrop= Iop x Rcx L Vdrop% = Vdrop ÷ Vop Vdrop= 8.23 A x 1.93 x .019= 301.79 mV Vdrop% = 301.79 mV ÷ 149 V = .002025 < 1% WIRING OVERCURRENT PROTECTION CONDUCTOR AMPACITY From PV Array 8.91 AISC x 1.25 = 11.14 A 11.14 A x 1.25 = 13.92 A Record High Temp. 39.4°C Ambient Temp. Adjustment for conduit exposed to sunlight on rooftops 22°C Ampacity Correction Factor = .58 CFtemp # of wires in conduit correction factor = .80 CFconduit 13.92 A ÷ (.58 x .80) = 30 A = 12 AWG USE-2
29. Calculations INVERTER KACO Blue Planet 360Ixi grid tied inverter max. continuous power at 40°C DC input voltage AC output voltage range MINIMUM INVERTER OUTPUT CIRCUIT CONDUCTOR AMPACITY Inverter continuous output rating = 3600 W Minimum Inverter Voltage = 125 V Max Operating Current = 3600 W ÷ 125 V = 28.8 A Min. Inverter Output Circuit ampacity = 28.8 A x 1.25 = 36 A
30. Calculations POINT OF CONNECTION sum of the supply breakers feeding the busbar of a panel can be up to 120% of busbar rating 100 A busbar 100 A main breaker 100 A x 120% = 120 A PV breaker = 20 A GROUNDING WEEB Grounding Washers (between module and rack) WEEB Grounding Lug (to rack) ARRAYMOUNTING INFORMATION Zep System II
