APsmart Rapid Shutdown System (RSD) Transmitter-PLC

The APsmart Rapid Shutdown System Transmitter-PLC is part of a rapid shutdown solution when paired with RSD-S-PLC, a PV module rapid shutdown unit.

The APsmart Transmitter-PLC is a key component of the APsystems Rapid Shutdown System (RSD) used in modern solar PV installations. It is designed to ensure module-level rapid shutdown compliance by sending a continuous communication signal to RSD devices installed on solar panels.

When operating, it provides a “heartbeat” signal that keeps the system active. When power is removed or an emergency shutdown occurs, the signal stops and all connected PV modules automatically enter rapid shutdown mode, enhancing system and firefighter safety.

Key Features

• Meets NEC 2017 & 2020 (690.12) requirements
• Meets SunSpec requirements
• Transmitter-PLC provides heartbeat signal to RSD-S-PLC. Signal stops when AC power is absent
• Optional outdoor enclosure
• Equipped with single/dual core
• Optional 85-264VAC power supply
• Optional 180-550VAC power supply

System Integration Overview

The Transmitter-PLC uses SunSpec-compliant power line communication (PLC) technology:

• It injects a communication signal through the PV wiring
• This signal is received by APsmart RSD (Rapid Shutdown Devices) on each module
• As long as the signal is present → system stays ON
• If signal stops (AC loss or manual shutdown) → modules shut down instantly

 This creates a fail-safe safety system required by NEC 690.12 regulations

Download

Datasheet
APSmart_Transmitter-PLC-datasheet_Rev2.9_2023-10-07-NA-1.pdf

User Manual & Installation Guide
RSD-DTransmitter-User-Manual_NA_EN_REV3.4_2025-07-01.pdf?

Certification


About APsmart

From the developers at APsystems, APsmart offers state-of-the-art PV module rapid shutdown devices (RSD-S-PLC and RSD-D), ideal for any new or existing string or central inverter system, and meeting U.S. NEC 2017&2020 690.12 Rapid Shutdown requirements. Leveraging APsystems’ proven expertise in module-level power electronics, APsmart solutions are powered by ASIC with internal IP and integrated with TI chips at the system-level application.