Archive

Posts Tagged ‘Square D Breaker’

Cutler Hammer Circuit Breaker Trip Indication

April 20th, 2012 1 comment

 

Cutler Hammer LD3450 Molded Case Circuit Breaker with Handle In Trip Position

Cutler Hammer LD3450 Molded Case Circuit Breaker with Handle In Trip Position

MIDWEST gets lots of phone calls from folks desperate for a little technical help. Sometimes they know very little about electrical equipment, circuit breakers for example. These are the most difficult calls because the caller may be putting themselves in harms way and not know it. We could tell them what to do, but unqualified people in the electrical power world need to hear “Hire an electrician, call a qualified person, call an electrical contractor.”  We might tell them to send us a picture of their circuit breaker and we can help them identify it, but get a qualified person to service or replace it. All too frequently the caller wants someone to tell them it is okay to just turn the breaker back on after it has tripped for no known reason. This can be very dangerous and against the code. For example, a maintenance mechanic called about a Cutler Hammer 450 amp molded case circuit breaker. This was a Cutler Hammer Catalog Number LD3450 circuit breaker. The breaker had tripped and one area of lighting in their plant was off.  He was told to “find the problem and turn the breaker back on.” Maintenance mechanics tend to be very resourceful individuals. And that is precisely what makes them dangerous around electrical equipment. They can fix mechanical problems, but most are not qualified around the dangers of electrical problems. In this case he thought the Cutler Hammer breaker was broken because the handle was in the middle and he could not close the breaker. It would have been easy to tell him how to reset the breaker so it would close. He was not overly interested in our requirement to have a qualified person investigate why a 400 amp Cutler Hammer breaker tripped. A lot of power or fault current went somewhere. The recommendation would have been the same for a GE General Electric circuit breaker, or Square D, Siemens, or old Westinghouse circuit breaker.  If the trip handle is in the middle, it tripped for a serious reason.  A qualified person has to investigate why. You can not just throw the power back on. And if you do not know how to reset a Cutler Hammer Series C industrial circuit breaker, you are not qualified.