Could use some help with this one. My electrical engineer is telling me that we need to reduce the size of our main breaker. He is reviewing our electrical design that has a 250 A breaker. without getting into too much detail, here is our installation:
the 600V main breaker feeds a distribution panel with 5 breakers. 4 of these are for heating loads and 1 is for a Control panel that feeds multiple motors. Each of the motors is individually protected by a combination motor starter, overload, overcurrent device. he is sizing the main breaker off of the sizing rules for motor overcurrent devices telling me it needs to be reduced to 200 A.
this makes no logical sense to me. it would be like telling me we have to resize our main breaker in the summer when we are not running the heating loads. or telling a homeowner to reduce his main breaker because he is not running his hot tub anymore.
Can someone please give me some backup to ask the right questions here. in my mind the main breaker is simply protecting the bus bars in the 600V distribution panel which are rated for more than 250A.
thanks
E
the 600V main breaker feeds a distribution panel with 5 breakers. 4 of these are for heating loads and 1 is for a Control panel that feeds multiple motors. Each of the motors is individually protected by a combination motor starter, overload, overcurrent device. he is sizing the main breaker off of the sizing rules for motor overcurrent devices telling me it needs to be reduced to 200 A.
this makes no logical sense to me. it would be like telling me we have to resize our main breaker in the summer when we are not running the heating loads. or telling a homeowner to reduce his main breaker because he is not running his hot tub anymore.
Can someone please give me some backup to ask the right questions here. in my mind the main breaker is simply protecting the bus bars in the 600V distribution panel which are rated for more than 250A.
thanks
E