Electricity Forum Electricity Today Magazine Arc Flash Training

Neutral Grounding Resistors (NGRs)


Advancements in Neutral Grounding Resistor Design

Neutral grounding resistors (NGRs) are critical components in power grids, safeguarding equipment from damaging fault currents. While traditional NGRs have served their purpose reliably, advancements in design are leading to improved cooling systems and integrated monitoring capabilities. These...

Maintenance and Reliability of Neutral Grounding Resistors

Neutral grounding resistors (NGRs) are essential components in power grids, playing a critical role in limiting fault currents during ground faults. While offering significant benefits for equipment protection, NGRs require proper maintenance to ensure their reliability and continued effectiveness....

Voltage Limiting Devices


Safeguarding Critical Infrastructure from Power Grid Transients

Overvoltage protection is essential for maintaining the integrity and reliability of critical infrastructure, particularly power grids. Voltage Limiting Devices (VLDs) play a pivotal role in protecting these systems from voltage spikes and transients that can cause extensive damage. This article...

Line Surge Arresters



Overvoltage Protection

Selecting the Right Voltage Limiting Devices (VLDs)

Voltage limiting devices (VLDs) play a crucial role in safeguarding equipment from damaging voltage spikes and transients in power systems. However, selecting the right VLD requires careful consideration of several factors, as an improperly chosen device might not provide adequate protection. This article explores the key challenges and considerations involved in selecting an appropriate VLD, focusing on response time, clamping voltage, and application requirements.

Understanding Voltage Limiting Devices

VLDs are designed to limit the voltage to a safe level within an electrical circuit, preventing damage caused by overvoltage conditions such as lightning strikes, power surges, or transient events.

Key Features of VLDs

  • Response Time: The speed at which the VLD can react to limit the overvoltage.
  • Clamping Voltage: The maximum voltage level that the VLD allows to pass through, beyond which it clamps down the excess voltage.

Challenges in VLD Selection

Selecting the appropriate VLD is not just about picking a device off the shelf. It requires a deep understanding of the system’s needs and the specific characteristics of the VLD.

Response Time Considerations

The response time of a VLD is critical, especially in systems exposed to fast-rising transients. A VLD with a rapid response time is essential to protect...

Overvoltage Protection Articles