Intelligent Power Today Magazine

News and Trends

Advanced protection against electromagnetic exposures and electric arc

HAZARDS AROUND

While working live in the energized grid, presence of voltage around the workers requires special attention. However, live-line (live working) techniques are widely applied for decades, several accidents in the past prove that the level of safety must be improved to minimize the number and seriousness of injuries in the future.
In the high voltage grid, bare-hand method is a common technique for safe live work. In the surroundings of any energized equipment,...

Buyer's Guide

News & Trends

2024 CE Code Training - Better Understanding of the Rules

CE Code training is intended to do a lot more than instruct about what changes have taken place since the last time Canada issued a national electrical code. We are producing a series of courses across Canada by one of Canada’s leading experts on the 2024 Edition of Canada’s Electrical...

Introducing Intelligent Power Today

Welcome to Intelligent Power Today Magazine, our publication that explores and explains the who, what, where, when, why and how of intelligent electrical devices, a collection of complex mechanical devices and sophisticated control systems used in industrial, commercial, and institutional...

State of Industry

Illuminating Decisions: EPRI Lights the Way for Modern Lighting Adoption

Facility managers and operators understand the critical role lighting plays in their daily operations. Accounting for roughly 30% of a commercial building's energy load, lighting significantly impacts energy consumption and associated maintenance costs. However, focusing solely on the...

Electrical Protection

Protecting Industrial Control Circuits

Addressing relay challenges with the modern technology

BY MARK STEPHENS & ALDEN WRIGHT, Electric Power Research Institute

In 2009, the Electric Power Research Institute (EPRI) began an effort to create improved alternating current (AC) “ice cube” relays that could withstand voltage sags without dropping out.

Their white paper entitled “AC Ice Cube Relays Applied for Improved Power Quality” outlined the basic design and vulnerability of these common devices that often appear in modern industrial control circuits. These are called “ice cube” because they are housed in clear plastic having the appearance of an ice cube (see photo).

Similar appearing relays with direct current (DC) coils are generally robust to common power quality problems as long as their corresponding DC power supplies are robust as well. However, “ice cube” relays with AC coils have shown extreme sensitivity to voltage sags.

With an average dropout at or near 70 percent of nominal...

Electrical Protection Articles

Generator Protection

Coordinating Protection for Generator Safety

The reliable operation of a power grid hinges on the proper functioning of its generators. Protecting these critical assets from internal faults and external disturbances is paramount. However, achieving this protection presents a complex challenge – ensuring fast fault clearing times to...

Lightning Protection Systems

Fire Prevention: Role of Lightning Protection in Mitigating Fire Risks

Lightning strikes pose a significant fire risk to buildings, structures, and natural areas, capable of igniting devastating fires within seconds. Lightning protection systems (LPS) play a crucial role in mitigating these risks by safely dissipating the electrical energy of a strike. This article...

Overcurrent and Short Circuit Protection

Arc Flash Hazards: Understanding the Risks and Implementing Protective Measures

Overcurrent faults, including short circuits, pose a significant threat within electrical systems. Beyond equipment damage and system outages, these faults can also lead to a dangerous phenomenon known as an arc flash. Arc flashes are intense electrical discharges that generate extremely high...