Minimize arc flash risk
By Mary Del
Kirk Key Interlock Company and Utility Relay Company (URC) have developed a new product use recommendation to increase safety during power substation maintenance. By combining Kirk’s new Power Panel Switch (PPS) and door interlocks with URC’s Quick-Trip system, arc flash hazards can be reliably reduced when feeder breakers are racked in or out for maintenance, the company says. Kirk’s interlocks prevent access to feeder compartments until URC’s Quick-Trip system is enabled. Kirk’s PPS switch interlock and door interlocks are available in standard duty, medium duty and heavy duty configurations. When integrated with the Quick-Trip, the PPS replaces a standard padlock, which does not provide isolation or ensure that the operator has properly activated the Quick-Trip. Turning the Kirk PPS key activates the arc hazard system and releases the key. The released key is then used in the next sequence of safe operations; in this case, releasing the keys needed to unlock the feeder compartment doors, fitted with Kirk interlocks. Until the feeder compartments are locked and the keys returned, the first key, which is needed to turn off the Quick-Trip system, will not be released. The system ensures that feeder compartments are never accessed unless the Quick-Trips system is engaged. URC’s Quick-Trip has been designed to shorten the trip time of an upstream breaker during maintenance.