Although a PV isolator switch does not have to be replaced as frequently, periodic checks are necessary to ensure functionality and safety. In particular, PV isolator switches are designed to resist adverse conditions, such as dust, water, and temperature fluctuations, characteristic of outdoor solar installations. While high-quality isolator switches may last for 10 to 15 years or more, other factors such as exposure to the environment may decrease or increase their lifetime; frequency of usage; and load demands.
Experts also highly recommend checking a PV isolator switch at least once a year in one’s routine system maintenance. Signs of wear, such as corrosion, discoloration, or difficult operation, generally mean that replacement is required sooner rather than later. For very demanding commercial installations with system voltages of up to 1500V and frequent switchings, technicians may advise replacements between 5 to 10 years for maximum reliability and safety.
The NEC insists on safety and continued performance of the components in the electrical system, such as the isolator switch, especially indispensable in high-voltage installations. In doing so, it will evade possible safety hazards that also protect the equipment and personnel against electrical shock in time for the replacement of damaged or malfunctioning switches. Solar Industry Magazine cited that as many as 20% of the reported failures in PV systems are because of defective isolator switches, which should urge proactive replacement once performance deteriorates.
Being mostly residential systems, the replacement of the PV isolator switch is normally less frequent owing to lower voltage levels and operation demands. The replacement, however, has to be checked in 5-year phases so that it can be sustained in good position. While the isolator switches are designed for durability, their replacement may be fairly reasonable for solar system owners, lying within the $50-$200 average, depending on the model and specification.
Ensuring a high-quality, reliable-over-time operating PV Isolator Switch in the PV system can be very critical with respect to both safety and efficiency. This performance monitoring, coupled with the implementation of recommended inspection intervals, can provide safe operation without interruptions simply by replacing the switch, thereby protecting investment in solar technology.