CP Switchgear Adds CB-7745 High Current Relay Test Set

Article By: cpswitchgear.com



Originally Posted: Jan 12, 2009

Carolina Precision Switchgear adds CB-7745, High Current Relay Test Set

It was time to hit the road for Doug Weaver and Barry Welch and head for Maryland to pick up the latest in Carolina Precision Switchgear’s arsenal of test equipment. In an effort to better serve our clients from a mobile service perspective, it is necessary to have the proper electrical switchgear test equipment. After a full day of driving from Charlotte, NC to New Windsor, Maryland, the two arrived at the ETI test facility.

Doug & Barry were there to oversee and watch the calibration of the CB-7745 low voltage circuit breaker test set. The first task was to change the tap setting from 208v to the 480v setting. The test set is also capable of being energized from a 600v source. The high current relay test set performed flawlessly during the calibration process. Once all of the tests were performed, the CB-7745 was readied for transport in the new Carolina Precision Switchgear mobile enclosed trailer.



The primary injection test set is a model CB-7745 with a new MAC-20 digital upgrade. The MAC-20 has a serial port to connect to a PC so a computer read out of the tests can be captured. The CPS owners used the type of relay test set and MAC-20 upgrade during their service with Duke Energy. Carolina Precision Switchgear has served the needs of Duke Energy for years. You can be assured that if Duke Energy uses CPS services that your company can also trust the electrical switchgear services that we provide. This is one of the most durable and accurate circuit breaker test sets on the market. We firmly believe the only way to accurately test a relay on a low voltage circuit breaker is to use primary injection. Secondary injection will only test the relay and does not use the entire circuit for opening the breaker. Primary current injection goes through the entire circuit of the breaker, including the current transformer’s, ( CT’s). This is extremely important to verify the CT’s will recognize the current overload which will then trip the breaker on a relay timeout.

For more information, please visit www.cpswitchgear.com or call Carolina Precision Switchgear at 704-596-4242.