SMA's SunSpec Rapid Shutdown Device works in tandem with SMA Sunny Boy -41 inverters to bring NEC 2017 Rapid Shutdown Compliance for module-level shutdown of a grid-tied solar PV system. Rapid Shutdown takes place via power line communication with the SunSpec signal - by using the existing DC power lines between the SMA inverter and the PV array, installation of the SunSpec Rapid Shutdown Device is made significantly easier.
Note: JMS-F has replaced SMA's older TS4-R-F rapid shutdown device. Though the JMF-S performs the same function as the TS4-R-F, SMA states that the two devices should NOT be mixed on the same inverter/system.
Note: The JMS-F is NOT compatible with the Sunny Boy inverters' Secure Power Supply (SPS) feature.