Article Name
Surge protection in industrial control cabinets By Abhishek Jadhav for DigiKey
Control cabinets serve as the powerhouse of any industrial facility, housing programmable logic controllers (PLCs), communication devices, sensors, variable frequency drives, and human-machine interface panels. As these components become more compact and complex, their susceptibility to damage from transient overvoltage increases. These transient overvoltages are short-duration (typically milliseconds), high-magnitude voltage peaks with fast-rising edges, capable of reaching up
to 6,000 volts even on a low- voltage consumer network. When a voltage surge exceeds the specific dielectric strength of the devices, it can affect the entire electrical system. It leads to short circuits, equipment damage, fire hazards, and even complete failure of facility operations. The primary causes for these transient overvoltages include lightning strikes, switching operations, and electrostatic discharge. Among these, lightning strikes are the most common source of power surges. Even
indirect effects of a lightning strike can induce a surge voltage. The electromagnetic field created by the lightning current generates resistive and inductive coupling, which can potentially cause severe equipment malfunctions or permanent damage. Industries must integrate surge protection devices and strategies to safeguard electrical and electronic equipment within control cabinets. These devices detect and divert impulse current and transient overvoltages away from sensitive systems, ensuring
16
Powered by FlippingBook