On the final day of NECA 2021, Karla Zavala, who is currently responsible for several of ABB's surge protection devices (SPDs), discussed the importance of surge protection and why the need for SPDs will only continue to expand in her presentation, "Why the Increased Need for Surge Protection?"
First, Zavala defined what a surge is. Also known as transients, surges are brief overvoltage spikes or disturbances on a power waveform that range in length from 1 nsec to 100 µs, according to the IEEE standard. While 80% of surges are internal disturbances (e.g., load switching), 20% are external (e.g., lighting strikes), which are the more serious of the two. “They can be very devastating because they can damage your equipment,” said Zavala.
That’s where SPDs play an important role. They are defined as a non-linear protective device for limiting surge voltages on equipment, and there are four major reasons for surge protection: eliminating equipment failure, reducing operational downtime, reducing frequent maintenance or repairs, and complying with the NEC.
Next, Zavala explained the role the NEC plays in increasing the demand for SPDs. She noted there are currently eight locations in the NEC that define SPD requirements: Sec. 708.20(D), Sec. 700.9, Sec. 695.15, Sec. 694.7(D), Sec. 670.6, Sec. 645.18, Sec. 620.51(E), and Sec. 230.67(A). And each new version of the NEC is expected to continue to add new requirements for SPDs. “This further validates why we’ll continue to see the need for surge protection moving forward,” she added.
Zavala then defined the four types of SPDs: Type 1 (line side or load side), Type 2 (load side), Type 3 (point of utilization), and Type 4 (din-rail). It’s important to understand the Code and requirements when choosing the type of SPD to use.
Lastly, Zavala described applications for SPDs, such as elevators, escalators, moving walkways, outdoor lighting, motor control centers, fire pump controllers, and more. Newer ones that she says will continue to grow in importance include LED signage such as billboards, which are elevated and susceptible to lighting strikes, and electric vehicle chargers, which require SPDs inside of charging stations and the buildings to which they’re connected.
