Circuit Switchers

As utilities continue to face an aging infrastructure as well as rapid commercial and residential growth, many are tasked with replacing and adding new protective equipment to address increased fault level requirements as well as system growth. One of the most critical pieces of equipment a utility should look to develop a thorough understanding of is the protective device located on the primary side of their power transformers. These can help to minimize the risk of costly equipment damage as well as extend customer outage times when interruption of fault currents must take place.

Key factors to consider when selecting a primary-side protection device include overall device reliability, the coordination complexity and requirements of the system, its interruption capability of transformer limited faults, as well as its geographical and environmental footprint. Based on a utility’s unique requirements, it may employ power fuses, circuit breakers, or circuit switchers as the primary overcurrent protective device.

This bulletin highlights what primary-side protection devices are available to utilities as well as the considerations to make when making an appropriate selection. In addition, it showcases the Southern States line of circuit switcher products.