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.

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 ...

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 ...

Often we try to find solutions to common power magnetics issues in engineering manuals. In the process, we encounter conflicting theories among publications with no definitive solutions offered. This ...

Transformers are very reliable devices and can provide service for a long time if regularly maintained and serviced. They’re also the single most costly item in any substation. To protect against ...

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 ...

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