HomeMy WebLinkAboutPV Worksheet Micro-Inverter Array (2)
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PHOTOVOLTAIC SYSTEMS
PV WORKSHEET – MICRO-INVERTER ARRAY
Solar photovoltaic (PV) systems have widely gained acceptance as an alternative energy
source and installations range from the small array supplying a bus stop luminaire to a
large array that covers acres. Since each installation comes with its own characteristics
this worksheet has been provided for the installer to complete and submit with a Solar
Photovoltaic (PV) Permit Application. With this information in advance the inspector
can get a good idea of what the project entails and perhaps warn the installer of an
electrical code issue before the installation is complete. The entire PV system
installation shall comply the Article titled Solar Photovoltaic (PV) System in the currently
adopted National Electrical Code (NEC).
The following documentation must be provided with the PV Permit Application:
1. Pages 2 and 3 of this document
2. Equipment spec/cut sheets for grounding/bonding fittings, modules, inverters,
micro inverters, or optimizers (if these are not available complete page 4 of this
document)
3. A one-line diagram of the PV system including service interconnection
4. A site plan showing the relative location of the array and the PV equipment on
the property. Also provide location of service and distance from array.
5. Roof mounted arrays shall have engineering certifying the existing roof will
support the imposed load.
6. Roof mount and Ground mounted arrays shall be engineered to withstand 125
mph wind load.
A PV installer is allowed to construct the support system, mount the modules, inverters
or optimizers, and connect the factory provided module wiring harness (plug and play).
The remainder of the installation such as panel boards, raceways, boxes, fittings,
breakers, and building wire shall be installed by a licensed electrical contractor.
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MICRO-INVERTER ARRAY
PV SYSTEM INFORMATION
TYPE OF ARRAY
Y N Y N
Roof Array? ☐ ☐ Rapid Shutdown Required (690.12)? ☐ ☐
Ground Array? ☐ ☐ Guarding of Conductors Required (690.31A)? ☐ ☐
PV SYSTEM OVERVIEW
Maximum System Voltage
# Modules/String
# Strings in System
Maximum Circuit Current
Battery Storage? Y N
CALCULATIONS:
MAXIMUM SYSTEM VOLTAGE – 690.7(A);
(Voc) (module label) X Thermal Coefficient3 X # of modules/string = VMAX
MAXIMUM CIRCUIT CURRENT - 690.8(A)(1):
(Isc)(module label) X (Sum of the paralleled modules) X 125% = IMAX
OVERCURRENT DEVICE RATING – 690.9(B):
( Imax ) X 125% = OCPD2
1Supply side connections may be allowed by your utility and shall comply with 705.12(A)
2OCPD – Overcurrent Protective Device
LOAD SIDE CONNNECTION1
Service Voltage
Service Panel Main Breaker
Service Panel Bus Rating
Service Conductor Size
PV System OCPD2 Rating
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MICRO-INVERTER ARRAY
CONDUCTOR AND RACEWAY
SCHEDULE
Conductor Type Conductor
AWG
Conduit
Type
Conduit
Size
1 PV Source Conductors
USE-2 PV Wire
MFG
Cable NA NA
2 Exterior Cable Listed With Inverter MFG
Cable NA NA
3 Grounding Electrode Conductor/
Equipment Grounding Conductor
.
.
NA NA
4 THWN-2 XHHW-2 RHW-2 .
.
.
.
.
.
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MICRO-INVERTER ARRAY
COMPONENT RATINGS
PV MICROINVRTER RATINGS
Module Name
Module Model
Maximum Voltage
Maximum Current
Maximum Power
Maximum # Units/20A Circuit
Thermal Coefficient3
3Use thermal coefficient as provided by manufacturer. If not provided, use 1.20. (690.7)