Nov. 13, 2008, PULLMAN, WA - Schweitzer Engineering Laboratories, Inc. (SEL) is now taking orders for two new products, the SEL-787 and SEL-487E Transformer Protection Relays. These are the first ...

A transformer switching onto a line can sometimes cause a circuit breaker to trip or a fuse to blow. This phenomenon occurs even if the transformer presents no load, such as when the secondary is open ...

Inrush currents associated with motor starting and transformer energizing can cause interaction problems with other loads in a facility or on the power system, particularly sags that trip loads.

This month in EC&M's forum for your power quality questions, Mark McGranaghan, vice president of consulting services, teams up with several other experts from EPRI-PEAC to address the topics of ...

The latest version of RelaySimTest (V3.20) enables users to extend the benefits of system-based testing to transformer protection 1. Instead of adopting the usual approach of simply testing the ...

Omicron has introduced a way to test current transformers at all lifecycle stages by using a testing method called "the modeling concept". The "traditional" way of testing a current transformer is to ...

A simple approach based on original research attacks inrush currents at the source - the power transformer. The use of special core materials and transformer design/construction techniques overcomes ...

Omron Electronic Components Europe has launched the G5Q-HR, the latest addition to the G5Q family of 10A PCB power relays. Credit: Omron The new relays can achieve reduced power consumption and heat, ...

However much care is taken, it is very difficult to keep all traces of transformer-induced hum out of the signal circuitry. It is highly irritating to find that despite the cunning use of low-noise ...

Distributed generation, also known as embedded generation, is a hot topic at the moment. With more and more generation being connected to the network, those concerned with its stability have to deal ...

Rectifiers and ac-dc power supplies employ large bulk capacitors. During power-up, these capacitors require a large amount of current to charge up, resulting in a large inrush current. This inrush ...