Grid Interconnection

1. PROJECT DESCRIPTION:

10. PHOTOVOLTAIC AMPACITY & WIRE CALCULATIONS--(3636 MURILLO AVE, SAN JOSE) SHEET PV-10
Solar Module Specifications: Inverter Specifications:
Module Model Number: YING-LI YL 230 P-29b Inverter Model Number: SOLECTRIA SGI 500
Module Weight: 43 Pounds
Module Length: 65.0'' Width: 39.0'' Depth: 2.0'' Nominal Voltage: 480 Volts (AC)
Max Inverter Output Current: 602 Amps
Voc (open-circuit Voltage): 37.0 Volts (DC)
Vmp (max-power Voltage): 29.5 Volts (DC) Number of Inverters: 5
Isc (short-circuit current): 8.40 Amps Number of Modules per String: 14
Imp (max-power current): 7.80 Amps Total Number of Strings: 936
Mfr Voc Temp Coefficient: -0.37 %/°C Total Number of Modules: 13104
Total System Size: 3013.92 kWstc
Maximum PV System Voltage and Current Calculations:
Record Low Temp. (°C): 0
ASHRAE Appendix E: SJC Airport
Mfr Voc
Voltage Correction per Mfr Spec: = x (25°C - Record Low Temp.) + 1 = 1.093
Temp Spec.
Maximum PV System Voltage per NEC Voltage Correction Number of Modules in
= x Voc x = 566.2 Volts
690.7 per Mfr Spec Series
Maximum PV Continuous Current per
= 1.25 x Isc x Number of Strings = 9828 Amps
NEC 690.8(A)(1)
DC Conductor Ampacity Calculation:
Number of Strings: 1 Number of Current-Carrying Conductors: 2
Expected Wire Op Temp. (°C): 40 Conduit Fill Correction per NEC 310.15(B)(2)(a): 1.00
Temp. Correction per Table 310.16: 0.91
Circuit Conductor Size: AWG #8 Circuit Conductor Ampacity: 55 Amps
Required Circuit Conductor Ampacity
= 1.56 x Isc x Number of Strings = 13.2 Amps
per 690.8(A)&(B)
De-Rated Ampacity of Circuit Temp. Correction per NEC Table Conduit Fill Correction per NEC
= x
Conductor per NEC Table 310.16 310.16 310.15(B)(2)(a)
Length of Conduit Run (ft) 200 x Circuit Conductor Ampacity = 50.1 Amps
Voltage Drop 0.62%
DC Conductor Ampacity Calculation:
Number of Strings: 24 Number of Current-Carrying Conductors: 2
Expected Wire Op Temp. (°C): 40 Conduit Fill Correction per NEC 310.15(B)(2)(a): 1.00
Temp. Correction per Table 310.16: 0.91
Number of Parallel Conductors: 1
Circuit Conductor Size: 500 kcmil Aluminum Circuit Conductor Ampacity: 350 Amps
Number of
Required Circuit Conductor Ampacity Number of
= 1.56 x Isc x / Parallel = 314.5 Amps
per 690.8(A)&(B) Strings
Conductors
De-Rated Ampacity of Circuit Temp. Correction per NEC Table Conduit Fill Correction per NEC
= x
Conductor per NEC Table 310.16 310.16 310.15(B)(2)(a)
Length of Conduit Run (ft) 300 x Circuit Conductor Ampacity = 318.5 Amps
Voltage Drop 1.21%

11. AC Conductor Ampacity Calculation (Between Inverter & Transformer):
Expected Wire Op Temp. (°C): 40 Number of Current-Carrying Conductors: 3
Temp. Correction per Table 310.16: 0.91 Conduit Fill Correction per NEC 310.15(B)(2)(a): 1.00
Number of Parallel Conductors: 2
Circuit Conductor Size: 500 kcmil Circuit Conductor Ampacity: 430 Amps
Required Circuit Conductor Ampacity Maximum Inverter Number of Parallel
= 1.25 x / = 376.3 Amps
per 690.8(B) Output Current Conductors
De-Rated Ampacity of Circuit Temp. Correction per NEC Table Conduit Fill Correction per NEC
= x
Conductor per NEC Table 310.16 310.16 310.15(B)(2)(a)
Length of Conduit Run (ft) 50 x Circuit Conductor Ampacity = 391.3 Amps
Voltage Drop 0.34%
AC Conductor Ampacity Calculation (Between Transformer & Point of Interconnection):
Expected Wire Op Temp. (°C): 30 Number of Current-Carrying Conductors: 3
Temp. Correction per Table 310.16: 1 Conduit Fill Correction per NEC 310.15(B)(2)(a): 1.0
Circuit Conductor Size: AWG #2 MV-105 Circuit Conductor Ampacity: 165 Amps
Transformer
Required Circuit Conductor Ampacity Maximum Inverter
= 1.25 x x 5 Inverters / Voltage of = 144.9 Amps
per 690.8(B) Output Power of 500 kW
12.47 kV
De-Rated Ampacity of Circuit Temp. Correction per NEC Table Conduit Fill Correction per NEC
= x
Conductor per NEC Table 310.16 310.16 310.15(B)(2)(a)
Length of Wire Run (ft) 2000 x Circuit Conductor Ampacity = 165 Amps
Voltage Drop 0.54%
Summary for Inverters A, B, C, D:
DC Specs: Maximum Short-Circuit Current: 2016.0 Amps
Maximum System Voltage: 566.2 Volts
Operating Current: 1497.6 Amps
Operating Voltage: 413.0 Volts
AC Specs: Operating Voltage: 480 Volts
Maximum Continuous Current: 602 Amps