We have recently become aware of a potential issue with the connection between the clusters and the stabs on some draw-out type Masterpact NW breakers. This issue impacts only the draw-out version of the ANSI and UL listed Masterpact breakers. Fixed mounted Masterpact NW breakers, IEC Masterpact NW and draw-out versions of Masterpact NT breakers are not impacted.
We are currently engaged in a comprehensive investigation and review of the situation. We will communicate promptly the results and conclusions of our investigation and review them with you as soon as we have completed that activity. In the meantime, we ask that you follow the proposed course of action:
• Circuit breakers that are currently racked in, closed and energized do not pose a hazard and should be left in service. These breakers will operate properly and can be operated either on or off as long as they are maintained in the connected position. We will contact you in the near future about whether or not they will require any further servicing.
• If it becomes necessary to rack a circuit breaker out (test or disconnected positions), it is our strong recommendation that to avoid the potential for personal injury or property damage, we request that you not rack the breaker back into connected position until you have contacted Square D and arranged for a qualified Square D Services technician to be available to manage and assist racking the breaker back in before energizing it.
• If you have a current project where energization is about to take place, we also ask that you please contact Square D Services and arrange for one of our qualified service technicians to review and inspect the Masterpact NW breakers prior to energization.
• If in the event of an emergency it becomes necessary to rack a breaker in and energize it without the assistance of a qualified Square D services technician, we strongly recommend that you review and comply at a minimum with NFPA 70E requirements.