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The Solar ABCs is a collaborative effort among experts to formally gather and prioritize input from the broad spectrum of photovoltaic stakeholders resulting in coordinated recommendations to codes and standards making bodies for existing and new solar technologies.

The Solar ABCs is supported by the U.S. Department of Energy under Award Number DE-FC36-07GO17034

Solar ABCs Newsletter
March 2013
In This Issue
Report & Webinar: Angle of Incidence Effects
Register now for Solar ABCs Stakeholder Meeting in San Francisco
Review of Draft Ground-Fault Blind Spot Report
Proposal for new PV Fire Classification Test
2015 IFC/IRC Proposed Code Changes Available
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Welcome to the March newsletter for the Solar America Board for Codes and Standards (Solar ABCs).   The Solar ABCs newsletter provides the latest news and information about solar codes and standard achievements, announcements, and events. Please contact me if you have any questions or comments.




Larry Sherwood
Project Administrator
Solar America Board for Codes and Standards  
Solar ABCs Report and Webinar:
Angle of Incidence Effects on PV Modules


The Solar ABCs recently published a report that details a study that tested and validated the draft International Electrotechnical Commission (IEC) 61853-2 standard's experimental procedures and related mathematical models for the measurement of angle of incidence effects on photovoltaic (PV) modules. This new Solar ABCs study report entitled Validation of Draft International Electrotechnical Commission (IEC) 61853-2 Standard: Angle of Incidence Effect on Photovoltaic Modules written by Govindasamy (Mani) TamizhMani, Ph.D presents findings based on two rounds of test results.


This study is a continuation of a previous Solar ABCs' project to test and validate the IEC 61853-1 standard. A report summarizing that project is also available online, entitled  Photovoltaic Module Power Rating per IEC 61853-1 Standard: A Study Under Natural Sunlight, which was published in March 2011.


The Solar ABCs will hold a stakeholder webinar to give a brief overview of this new report on April 15, 2013 at 3pm EDT (2pm CDT, 1pm MDT, 12am PDT). The webinar is free, but you must  register to attend.

Solar ABCs Stakeholder Meeting: Register Now

July 11, 2013, 2-6pm, San Francisco, CA


Be sure to join us for the Solar ABCs annual 2013 Stakeholder Meeting in San Francisco, California on July 11, 2013. This meeting is free to attend and is conveniently scheduled during the Intersolar North America Conference. The Solar ABCs holds an annual meeting to provide PV stakeholders with an update and overview of major Solar ABCs projects and other PV codes and standards activities. Register Now.   

Solar ABCs Ground-Fault Blind Spot Report

The ground-fault blind spot safety issue came to light during studies of two well-publicized PV system fires. The first occurred on April 5, 2009, in Bakersfield, California. The second occurred on April 16, 2011, in Mount Holly, North Carolina. Based on the evidence found at these two fires, it is believed that traditional, fuse-based ground fault protection schemes did not detect certain ground faults that can occur in grounded PV systems. These undetectable faults fall within a detection "blind spot" inherent in the majority of U.S. PV installations.


Over the last twelve months, the Solar ABCs has led a broad industry- and stakeholder-based working group to research this problem and develop effective mitigation strategies. This research built on earlier work that provided a basic explanation of the cause of the detection blind spot. It includes results of field research conducted to characterize basic array wiring impedance properties and their effects on ground fault detection, circuit modeling and analyses of high and low impedance faults that may occur throughout the array, and a technical review of the effects of ground fault detection blind spot on different array topologies (grounded, ungrounded, and grounded through the ac connection).


Solar ABCs has developed a draft report including discussion of mitigation methods. Solar ABCs will host a webinar to provide a briefing on the draft report and solicit input and suggestions on May 2 at 2pm EDT. You can register to participate in the webinar here.


After this input, Solar ABCs will prepare a final report. A webinar on the mitigation methods suggested in the final report is tentatively scheduled for June 25 at 2pm. An announcement for that webinar will be sent at a later date.   
New Fire Classification Test Submitted to UL 1703 Standard Technical Panel
A proposal for a new fire classification test was recently submitted to the UL 1703 Standard Technical Panel for ballot.  The new test changes the basis for PV Fire Classification Rating from a test of module flammability only to a test of the PV system that includes the module, mounting hardware, and roof covering.  The new test was developed over the last two years based on results of tests sponsored by Solar ABCs and conducted at the UL Fire Research Laboratory.  The results of these tests are posted on the Solar ABCs web site.  The STP balloting will close at the end of April.
2015 IFC and IRC Proposed Code Changes Available and Hearing

The current list of proposed changes to the Group B codes, which include the IFC and IRC codes, is now available for review online.  ICC Committee Action Hearings will meet on April 21-30 in Dallas to discuss, debate and take action on the code change proposals.

2014 National Electrical Code

Solar ABCs and SEIA Codes & Standards Group - A Fine Collaboration!


The National Electrical Code is revised every three years. The next Code will be published in 2014. The code cycle was very dynamic. There were 223 proposals for Articles 690 & 705. The number and content of the proposals prompted 10 panel proposals to consolidate and meet the intent of proposals on the same article. The resulting "Report on Proposals" was an alert to the PV industry, the Solar Energy Industries Association (SEIA) and the Solar ABCs that some proposals could be a huge barrier to the PV industry. That resulted in the best ever collaboration with the industry, firefighters, certification agencies and systems houses. The collaboration formed another 14 task groups to insure consensus responses in the form of public comments to proposed changes accepted by Code Making Panel #4. The resulting public comments submitted by the collaboration by SEIA resulted in all be accepted by the panel with only a few editorial changes.


The public comments submitted by SEIA through collaboration with Industry and Solar ABCs were accepted (mostly intact) and included the following sections.

  • 690.5(A)                 Ground-fault Detection and Interruption
  • 690.11                    Arc-Fault Circuit Protection (Direct Current)
  • 690.12                    Rapid Shutdown of PV Systems on Buildings
  • 690.35(C)              Ground Fault Protection in Ungrounded PV Systems
  • 690.41                    System Grounding.

A very significant proposed change included allowing a 1000Vdc threshold for PV systems except on residential dwellings. That change is expected to be approved by the Technical Correlating Committee (TCC) and if so will be part of the 2014 NEC. Many changes were processed to reorganize Article 690. Important definitions for technology advance for dc-dc converters were added. A contentious requirement for adding auxiliary electrodes (690.47) to rooftop systems was passed by a narrow vote and will be examined by the TCC with the outcome still uncertain. Details of the most important changes will be provided once the TCC has issued its findings in the June Newsletter.