Codes and standards apply to photovoltaic systems, even low-voltage systems, just as they do for any other electrical installation. The main guide to safe installation is Article 690 of the National Electrical Code (NEC), which spells out requirements for safe installations. Photovoltaic modules (panels) and other system components are also tested by nationally recognized laboratories. Contact your local building department office regarding applicable local codes and ordinances, and to find out the NEC version currently in effect.