15+ Countries, 150,000+ Units: Why Sag Protectors Sit in Factories Worldwide

A voltage sag is a brief drop in supply voltage that recovers within a short window, typically triggered by lightning strikes, grid faults, or large motor starts on the surrounding network — not by anything happening inside the factory. Equipment running fine-geometry processes, such as semiconductor and display tools, can fault or shut down from even a short sag, which is why compensation has to happen within a few milliseconds of the drop. WESCO’s TSP® (The Second Power) is a voltage sag protector built for exactly this purpose, and over 25 years it has been deployed to more than 150,000 units across 15+ countries in low-voltage (up to 1kV) facilities.

Picture an automotive parts line or a data center where a sag lasting less than 0.2 seconds resets a controller: the line stops, and the process has to be reverified before it restarts. That this scenario keeps recurring across different industries and different countries is exactly what shows up in WESCO’s deployment numbers.

Why voltage sags keep happening

IEEE research indicates that a typical industrial site experiences roughly 60 to 70 voltage sags per year. Most originate outside the plant — lightning strikes on nearby lines, short-circuit faults on the grid, or inrush current from large loads starting elsewhere on the network. Unlike a full outage, a sag resolves within a few hundred milliseconds, so equipment reacts before anyone on the floor can identify the cause.

Why low-voltage equipment is particularly exposed

SEMI F47 sets a minimum ride-through requirement for semiconductor and display tools: equipment should keep operating normally down to 80% of rated voltage for 1 second, 70% for 0.5 seconds, and 50% for 0.2 seconds. In practice, a lot of field equipment tolerates less than that, and sags that fall outside the tolerance envelope described by the published ITIC (CBEMA) curve still trip machines. WESCO TSP compensates within 2ms for small-to-mid-capacity units and 4ms for large-capacity units — fast enough to respond before equipment registers the voltage deviation.

A demand pattern that repeats across industries

Semiconductor, display, automotive, secondary battery, and data center facilities run very different processes, but on the low-voltage side they share the same exposure: a short sag turns into a process interruption or an equipment restart. Because one line stopping affects the flow of the whole process, sag compensation tends to function less like an optional add-on and more like a recurring baseline requirement across these industries. That shared vulnerability is a large part of why WESCO’s shipments span 15+ countries.

A 10-year design life without batteries

TSP runs on an EDLC ultra-capacitor-based, battery-free architecture. Unlike a standard UPS built around lead-acid or lithium batteries, its energy storage section carries a 10-year design life, which removes the need for periodic battery replacement during operation. Under normal conditions, the SCR stays conducting and passes grid power through as-is; it switches into compensation mode only when a sag is detected. That structure removes a separate maintenance burden tied to battery degradation and replacement scheduling.

What 25 years and 150,000 units show

Across 25 years focused on power quality, WESCO has shipped more than 150,000 TSP units to 15+ countries. That track record isn’t concentrated in one country or one industry. It reflects the same underlying problem — equipment stopping because of a voltage sag — recurring across multiple industries that run low-voltage equipment, and TSP being adopted as the response each time.

Key takeaways

• IEEE research puts typical industrial sag frequency at roughly 60-70 events per year.
• SEMI F47 and the ITIC (CBEMA) curve together define the ride-through bar and where real equipment falls short of it.
• WESCO TSP® compensates within 2ms (small/mid capacity) or 4ms (large capacity) using an EDLC-based, battery-free design.
• A 10-year energy storage design life removes periodic battery replacement from the maintenance plan.
• 25 years, 15+ countries, and 150,000+ units reflect a demand pattern that repeats across low-voltage facilities, not a one-off deployment.

Frequently Asked Questions

Q. What is TSP?

TSP® (The Second Power) is WESCO's voltage sag protector for low-voltage (up to 1kV) equipment. It uses an EDLC ultra-capacitor-based, battery-free design.

Q. Why do so many different industries need it?

Semiconductor, display, automotive, secondary battery, and data center facilities have different process layouts, but they share the same vulnerability: a brief low-voltage sag can stop production.

Q. How is it different from a standard UPS?

It does not use lead-acid or lithium batteries. Its energy storage section has a 10-year design life, so it does not require periodic battery replacement.