Rapid shutdown is an essential safety measure in solar installations, minimizing the risk of electrical shock during emergencies or maintenance. It quickly reduces the voltage in PV modules to a safe level, enhancing the safety of first responders and technicians. All the discussed in this article comply with the 2014, 2017, and 2020 NEC 690.12 Rapid Shutdown specifications when installed on each PV module.

These modules, also called MLPEs (Module Level Power Electronics), are designed to optimize performance, monitor output, and provide rapid shutdown capabilities at the solar module level.

The TIGO TS4-A-O Rapid Shutdown Module

The TIGO TS4-A-O unit is a versatile component compatible with most panels and inverters, designed to enhance safety during emergencies. Rated for PV modules up to 700W, the TS4-A-O stands out due to its optimization feature. This unit provides module-level monitoring, optimization, and rapid shutdown.

What is Optimization?             

Optimization ensures that each solar module operates at its maximum efficiency by individually tracking and adjusting the current and voltage output. This is particularly useful in situations where shading, dirt, or varying panel characteristics could reduce system efficiency. The TS4-A-O unit improves the overall efficiency and energy yield of the entire PV system.

Installation and Features:

The TS4-A-O is easy to install and doesn't require many additional components, streamlining the installation process. Its monitoring capabilities through the Energy Intelligence Portal allow you to track system performance and pinpoint issues on specific modules. The TS4-A-O uses wireless communication via the TIGO Access Point (TAP) and the TIGO Cloud Connect Advanced (CCA), making installation straightforward. One TAP can communicate with up to 300 TS4s, and one CCA can collect data from up to 900 TS4s or up to 7 TAPs.

TIGO Access Point (TAP)

TIGO Cloud Connect Advanced

The TIGO TS4-A-S Rapid Shutdown Module

The TIGO TS4-A-S module features monitoring through the Energy Intelligence Portal and rapid shutdown capabilities but does not include optimization. It works seamlessly with the -O unit, allowing you to mix and match these units to meet your needs. The -S model also uses the TAP and CCA for wireless communication.

The TIGO TS4-A-F and TS4-A-2F Rapid Shutdown Modules

Both the TS4-A-F and TS4-A-2F units are IEC and UL certified, meeting NEC requirements for rapid shutdown. The -F stands for Fire Safety, excelling in its rapid shutdown feature. It is PVRSS Certified, tested, and UL certified with hundreds of top inverter models, and is rated for up to 700W per solar panel.

How They Work:

Both the -F and -2F units use Power Line Communication (PLC) via an RSS Transmitter to meet certification requirements. The RSS Transmitter emits a “Keep Alive” signal until a shutdown is initiated, which then kills the signal, shutting down the TS4 and reducing each PV module’s voltage to 0.6V in less than 30 seconds. Some inverters have built-in transmitters, eliminating the need for a separate RSS.

TIGO Single Core RSS Transmitter

TIGO Dual Core RSS Transmitter

Compatibility Note:

It's important to note that the -F and -2F units are not compatible with the TS4-A-O and TS4-A-S units due to different communication methods. This means you cannot use the -F or -2F modules in the same PV system as the -O or -S units if they share a common inverter.

The TS4-A-2F Module:

The TS4-A-2F unit can connect two modules and is rated for up to 1000W (500W per panel). It offers the same features and benefits as the -F unit, with the added advantage of connecting two panels with one unit. This makes the -2F a cost-effective solution, reducing labor and Balance of System (BOS) costs.

Choosing the Right Module

Choosing the right module for your solar setup depends on your specific needs:

• TS4-A-O: Ideal for systems with shading or varying panel characteristics where optimization is necessary.
• TS4-A-S: Suitable for systems where monitoring and rapid shutdown are required but optimization is not needed.

TS4-A-F and TS4-A-2F: Best for meeting rapid shutdown requirements in the simplest and most cost-effective way, particularly for larger systems or those focused solely on safety.

Installation and Compatibility

Installing these modules is straightforward thanks to their plug-and-play design. They are compatible with a wide range of solar panels and inverters, ensuring flexibility during setup. The modules slide onto the frame of your PV module, grounding themselves without the need for an extra grounding wire, simplifying the installation process.