The Tigo RSS (Rapid Shutdown System) Transmitter completes the cost-effective rapid shutdown system architecture when paired with Tigo's UL-certified Fire Safety solutions - including the TS4-A-F (add-on), TS4-A-2F (add-on for two modules). The RSS Transmitter sends a signal via PLC (Power Line Communication) to the TS4-F units to keep PV modules connected while powered on. TS4-F units automatically enter rapid shutdown mode when the RSS Transmitter is switched off and resume energy production when power is restored to the RSS Transmitter. The RSS Transmitter with Pure Signal technology can link multiple RSS Transmitters together, enabling one coordinated keep-alive signal to the array to maximize signal integrity, even in large and complex solar installations. This solution complies with NEC 2014, 2017, and 2020 690.12 rapid shutdown specifications utilizing power-line communication (PLC). Available with Pure Signal technology for multi-transmitter sites, as a Kit, DIN Rail, or PCBA for integration into inverters.