How To Plan Out An Array Of Solar Panels

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1 CITY OF DOWNEY COMMUNITY DEVELOPMENT, BUILDING AND SAFETY Brookshire Avenue Downey, CA ( B SECTION 01/01/2011 EFFECTIVE DATE PHOTOVOLTAIC 032 FORM NUMBER 2013 CBC CODE CYCLE 05/01/2014 REVISION DATE PHOTOVOLTAIC SYSTEMS INTRODUCTION The following information is presented as guidelines for Photovoltaic installations. These guidelines apply to all solar photovoltaic (PV) installations for Residential and Commercial installations. Areas of concern covered within this document include the structural and electrical elements of the 2013 California Residential Code (CRC) California Building Codes (CBC) 2013 California Electric Code (CEC), firefighter safety as regulated by the City of Downey Fire Department, utility requirements of Southern CA Edison, and the ability of the existing roof structure to support the additional loads of the arrays. Please Note: hand-written information will not be accepted ADMINISTRATIVE Provide 3 sets of plans, minimum size is 11 X 17 designed by an Electrical Engineer, Architect, or by the respective California Licensed Contractor installing the system. Plans are to include all manufacturers specification sheets, installation instructions, and U.L. listings. As per the Building and Professional Code all sets will be required to have a Structural or Civil Engineer stamp and wet signed with the supporting calculations for the entire panel mounting and rack assembly when not using an preapproved UL system or components. All sheets of the final plans, specifications, calculations and reports prepared by a civil, structural or architect shall bear the wet signed signature and stamp of the professional engineer or architect and the expiration date of the registration and plans prepared by a California Licensed Contractor shall bear the contractor s signature. The following clearances or approvals are required before a building permit can be issued: Planning Division Downey Fire Department Building & Safety Division Provide a statement on the title sheet of the plans that this project shall comply with the 2013 CBC, 2013 CRC, 2013 CEC and the City or Downey Municipal Code. SITE PLAN Provide fully dimensioned site plan drawn to scale. Show lot size, street, alley, easements, parking spaces, division walls, all projections, location, size and use of all structures on the lot and property line walls. Identify property lines, lot dimensions, distances from building to property lines and property line to street centerlines. Show the size and location of the service meter. Show the required working clearances around the Service meter main, AC Disconnect, Inverters, and DC disconnects. Show the required access, pathways, and smoke ventilation clearances around the arrays. 1

2 ROOF INFORMATION (ROOFTOP SYSTEMS) Show the following information on the plans: If the conductors are run through the roof and into the building, show method of conductor protection and note that the conduit is to kept 18 below the roof surface Weight of the arrays (pounds per square foot- including mounting hardware) If the array weight is less than 6 pounds per sq. ft., including the mounting hardware then engineering calculations are un-necessary for roof loading If array weight is 6 pounds per sq. ft. or greater, describe and show the roof structural elements, including: i) Rafter size ii) Rafter span iii) Rafter spacing iv) Roof sheathing v) Provide additional structural calculations and/or engineer s verification of load capacity of the roof structure. Identify roofing type (e.g. comp shingle, shake, light weight tile, etc.) Provide details of PV panel mounting hardware attachment to the roof framing members. Identify and show method of sealing the roof penetrations. (e.g. flashing, urethane caulking, etc.) Residential Access. Single ridge roof system. Provide two (2) three-foot wide accesses from the eave to the ridge where panels are located. Hip roof system. Provide one (1) three-foot wide access pathways from the eave to the ridge where panels are located. Hip and Valley roof systems. Modules shall not be located closer than 1-1/2 feet to a hip or valley if panels are located on both sides of the hip or valley. Modules shall be located no higher than three (3) feet below the ridge. Commercial Access. Provide a minimum six (6) foot wide clear perimeter around the edges of the roof. Exception: If either axis of the building is 250 feet or less, the perimeter may be reduced to four (4) feet. Center line axis pathways shall be provided in both axis of the roof. Provide a four (4) foot clear path to skylights and/or ventilation hatches. Provide a four (4) foot straight line clear path to the roof fire protection standpipe outlets. Provide four (4) foot clear width around roof hatch with at least one pathway not less than four (4) feet clear width to parapet or roof edge. Note on the site plan: The discharge of pollutants to any storm drainage system is prohibited. No solid waste, petroleum byproducts, soil particulate, construction waste materials, or wastewater generated on construction sites or by construction activities shall be placed, conveyed or discharged into the street, gutter or storm drain system. SUPPLIED DIAGRAMS Provide a minimum of a single-line diagram with the permit application package showing: Array configuration and Array wiring identified Combiner/junction box identified Conduit and size from junction box to PV power source disconnect identified Equipment and System grounding specified Disconnect specified Conduit and size from disconnect to inverter identified Inverter specified Conduit and size from inverter to AC disconnect to panel identified Point of connection attachment method identified Conduit to be run in attic space and/or routed under eaves out of view. (See Planning Department for options) 2

3 INVERTER INFORMATION Show the following information on the plans: Provide a cut sheet(s) for inverter(s) Show on plans, the inverter model number Provide the approval listing for utility interactivity Show maximum continuous output 25 C Show input voltage range of inverter Provide and show the grounding electrode conductor and associated ground rod or ufer attachment Provide and show a minimum of a #6 grounding conductor Provide and show grounding conductor protection Provide and show ground fault protection of inverter PV MODULE INFORMATION Show the following on the plans Provide a cut sheet for PV Modules Provide the approval listing for utility interactivity Show the open-circuit voltage (Voc) from the listing Show the maximum permissible system voltage from the listing. Show the Short-circuit current (lsc) from the listing Show the maximum series fuse rating from the listing Show the Maximum standard test conditions (Pmax) Show voltage at Pmax Show current at Pmax ARRAY INFORMATION Show the following on the plans, Number of modules in series. Number of parallel source circuits Total number of modules Operating voltage (number of modules in series X module Pmax.) Operating current. (number of parallel source circuits X module Pmax) Maximum system voltage (CEC690.7) Short-circuit current (CEC690.8) Roof mounted arrays for residential dwellings must have Ground Fault Protection (GFPD) (CEC690.5) WIRING AND OVERCURRENT PROTECTION Show the following on the plans, Wire type is 90 C wet rated Conductor amp capacity are sufficient i) PV source circuit current ii) PV source circuit amperage capacity iii) PV output circuit amperage capacity iv) Inverter output circuit amperage capacity Overcurrent protection on inverter output circuit is sufficient Point of connection meets provisions of CEC i) Point of connection panel bus bar rating Source circuit overcurrent protection is sufficient i) If inverter is not listed for no backup current, does each source have overcurrent protection in compliance with the listed maximum series fuse? ii) If inverter is listed for no backup current, overcurrent protection is not necessary if only two parallel strings are connected to the inverter. 3

4 Provide and show if the DC conductors are run inside of a building or structure, they shall be contained in a metallic raceway (conduit) or metallic enclosure, from the point of penetration to the first readily accessible disconnecting means per CEC section (E). The disconnecting means shall comply with sections (A) through (D). Provide and show the connectors shall be of the latching or locking type. Connectors that are readily accessible and that are used in circuits over 30 volts AC or DC, shall require a tool for opening and are required to be marked DO NOT DISCONNECT UNDER LOAD or NOT FOR CURRENT INTERRUPTING per section (C) & (E). Equipment grounding conductors shall be sized in accordance with table GROUND MOUNTED STRUCTURE Ground mounted systems are considered to be accessory structures and additional building structural and planning division approvals may be required. Weight of array (pounds per square foot- including mounting hardware) Provide details of the array supports, framing members, and foundation posts and footings. Provide details of the structural mounting. Structures above 6 feet high may require engineering calculations. Provide details on the module attachment method to mounting structure. BATTERY INTERCONNECT Fine stranded cables shall be terminated only with terminals, lugs, devices or connectors that are identified and listed for such use per section (F) and SYSTEM LABLES AND S Plaques shall be metal or plastic, with engraved or machine printed letters, or electro-photo plating, in a RED background with WHITE lettering, a minimum of 3/8 letter height, and all capital letters per the DFD requirements. Plaques shall be attached to the service equipment with pop-rivets, screws, or approved adhesive Show on the plans the required plaques to be installed on the Main Service Meter Panel and the disconnect means: To be installed on the face of the source disconnect means, for the direct current power source PHOTOVOLTAIC SYSTEM AC DISCONNECT RATED MPP CURRENT RATED MPP VOLTAGE RATED ISC RATED VOC MAXIMUM RATED OUTPUT CORRECT OF THE CHARGE CONTROLLER A V A V 4

5 To be installed on the face of the service meter panel 2 SOURCES OF POWER PV/AC DICONNECTE AT ADJACENT LOCATION DUAL POWER SUPPLY PHOTOVOLTAIC SYSTEM CAUTION: POWER TO THIS BUILDING IS ALSO SUPPLIED FROM THE FOLLOWING SOURCES WITH DISCONNECT LOCATED AS SHOWN CAUTION: SOLAR ELECTRIC SYSTEM CONNECTED Show on the plans the required plaques to be installed on the AC Disconnect: a. To be installed on the face of the AC disconnect CAUTION: SOLAR CIRCUIT DISCONNECT FOR UTILITY OPERATION If a switch or circuit breaker has all the terminals energized when in the open position, a label should be placed near it indicating AND/OR ELECTRIC SHOCK HAZARD DO NOT TOUCH TERMINALS. TERMINALS ON BOTH THE LINE AND LOAD SIDES MAY BE ENERGIZED IN THE OPEN POSITION INVERTER OUTPUT CONNECTION DO NOT RELOCATED THIS OVERCURRENT DEVICE ELECTRIC SHOCK HAZARD THE DC CONDUCTORS OF THIS PHOTOVOLTAIC SYSTEM ARE UNGROUNDED AND MAY BE ENERGIZED. TERMINALS ON BOTH THE LINE AND LOAD SIDES MAY BE ENERGIZED IN THE OPEN POSITION 5

6 Mounted on the inverter, Mounted by the Breaker in the Main Panel Mounted on the Inverter NEC Signage INVERTER PV SYSTEM ELECTRIC SHOCK IF A GROUN FAULT IS INDICATED, NORMALLY GROUNDED CONDUCTOR MAY BE UNGROUNDED AND ENERGIZED PV SYSTEM ELECTRIC SHOCK THIS EQUIPMENT SUPPLIED FROM MORE THEN ONE SOURCE TERMINAL MAYBE ENERGIZED IN OPEN POSITION PHOTOVOLTAIC SYSTEM AC DISCONNECT OUTPUT CURRENT OUTPUT VOLTAGE A V Show on the plans the required markings to be installed on the DC Circuits: Material used for marking shall be weather resistant. UL 969 shall be used as a standard for weather rating. Marking is required on all interior and exterior DC conduit, raceways, enclosures, cable assemblies, and junction boxes. Markings shall be placed every 10 feet, at turns, and above and/or below penetrations, and at all DC combiner and junction boxes. CAUTION: SOLAR CIRCUIT PHOTOVOLTAIC SYSTEM 600 VDC MAX CAUTION: SOLAR ELECTRIC SYSTEM CONNECTED 6

7 INSPECTIONS Photovoltaic systems are subject to multiple inspections, dependent on the type of systems installed and the attachment methods. Generally, the following inspections are applicable to most systems: 1. ROUGH INSPECTION: a. Framing Attachment inspection. This inspection includes any reinforcement of the existing roof structural members and the structural attachments (lag bolts) of the roof top PV panel support attachments. This is required prior to the installation of the roof flashings and panels. This is the most important structural inspection as it verifies the attachments necessary to achieve the wind loading requirements of the system. For ground mounted systems, an additional footing inspection may be required. b. Roof flashing inspection. This inspection includes the installation of the roof jack flashings and/or the moisture proofing of the roof attachments. c. Electrical rough in inspection. This inspection is the actual electrical rough inspection of the conduit and wiring methods, wire size and type, electrical connections, etc. Note: Roof mounted conduit IS NOT ALLOWED as per the City of Downey Municipal Code: conduit shall be run in the attic space and/or under the eaves when possible. Conduit to be painted the color of the surface it is attached to. (As noted on approved plan per Planning Department Approval) 2. FINAL INSPECTION: a. Placards/Labels. This inspection verifies the required placards and labels required by the electrical codes, utility provider, and the Downey Fire Department (DFD) requirements for firefighter safety. b. Grounding and Bonding inspection. This inspection is performed after the panels and a system component are installed and verifies the grounding and bonding integrity of the system. This inspection usually is combined with the rough electrical inspection. c. Photovoltaic final and release. This inspection is performed when all components are installed and functioning and serves as the utility release for the electrical interconnect. Failure to obtain the final electrical inspection will result in the utility not accepting your power into the utility power grid system. 7