TSUN PV Rapid Shutdown Solution

TSUN, a professional provider of energy storage solutions, has announced the launch of PV Rapid Shutdown Solution, which is a simple and economical Rapid Shutdown Solution that meets the requirements of the US NEC2017 690.12 standard. Adding the Rapid Shutdown Control Unit to the original PV system, when the PV module has a safety hazard, shutting the system down only needs one button. It can quickly turn off the corresponding PV modules within seconds, highly improves the safety of rescue, and reduces the loss of the PV system when it encounters a fire risk.

In the PV system, PV panels are connected in series, so the voltage of the whole line is accumulated and can easily reach to a high voltage of 600V-1000V. When fire occurs, as long as there is sunlight on the DC side, the panel will keep on generating power. But when the DC side is with a high voltage of 600V-1000V or even above, the firefighters will not be able to put out the fire taking direct risk of electric shock. Therefore, DC high voltage is a major problem for the safety of residential and industrial & commercial distributed PV systems.

Rapid Shutdown is a concept of assuring PV system safety introduced by US National Electrical Code (NEC). The main purpose is to protect firefighters, PV system installers and maintenance personnel. Back in 2014, NEC issued the standard “Component Level self-shutdown Solution” (NEC2014 690.12), which explicitly required that all PV systems in buildings should be equipped with rapid-shutdown switches, and the DC voltage of PV system needs to drop below 30V within 10 seconds. In the 2017 edition of NEC690.12, there was more specific requirement for this rapid shutdown – with a distance of 305mm from the PV array set as a limit, within 30 seconds after initial the rapid-shutdown switch, the DC voltage should drop below 30V outside the limit range and below 80V within the limit range.

The solar installers and owners need a reliable and durable Rapid Shutdown Solution which would be effective during the whole PV panels life cycle. TSUN Rapid Shutdown Control Unit is a cost-effective rapid shundown device. Through one-button operation, the DC high voltage will be limited to the roof or near the modules. In emergency situations such as fire, the personal safety of firefighter is protected to a certain extent to avoid electric shock accidents.