These requirements cover open@ enclosed and dead-front switches rated up to 1500 V dc@ intended for use in dc photovoltaic (PV) systems and installed in accordance with Article 690 of the National Electrical Code@ ANSI/NFPA-70. These switches are intended for ambient conditions between minus 20 to +50?? These requirements are intended to be used in conjunction with requirements in the Standard for Enclosed and Dead-Front Switches@ UL 98@ except as modified or supplemented by the following requirements. Unless otherwise specified@ when the term switch is used in this outline@ it refers to a photovoltaic@ enclosed@ open@ or dead-front switch. Fusible switches are intended for use with photovoltaic (PV) fuses which comply with the requirements of Outline for Low-Voltage Fuses ?C Fuses for Photovoltaic Systems@ UL 2579. These requirements also apply to open type switches@ used in conjunction with the Outline of Investigation for Open Type Switches@ UL 98A. These requirements also cover fused and unfused electrically tripped PV switches.
UL SUBJECT 98B-2015 history
2015UL SUBJECT 98B-2015 Outline of Investigation for Enclosed and Dead-front Switches for use in Photovoltaic Systems (Issue 3)
2014UL SUBJECT 98B-2014 Outline of Investigation for Enclosed and Dead-front Switches for use in Photovoltaic Systems (Issue 2)
1970UL SUBJECT 98B-2010 SUBJECT 98B OUTLINE OF INVESTIGATION FOR ENCLOSED AND DEAD-FRONT SWITCHES FOR USE IN PHOTOVOLTAIC SYSTEMS ISSUE NO: 1