Testing Electrical Switchgear With The CB-7745

Article By: cpswitchgear.com


Originally Posted: Jan 15, 2009

CB-7745 with a new Mac 20 digital upgrade. Electrical Switchgear Test Set

Carolina Precision Switchgear now operates with one of the premier pieces of electrical switchgear test equipment available today. This 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 CB-7745 is widely used by Carolina Precision Switchgear in our work at Duke Energy. 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 current transformer will recognize the current overload which will then trip the breaker on a relay timeout.

Photo shows Loading up the CB-7745 and taking it home

The CB-7745 current breaker test set is capable of pumping out 40,000 continuous amps. Amps of this magnitude are essential for proper testing of low voltage 480/600 volt circuit breaker relays on the instantaneous test.

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