We have two circuit breakers, a 70amp double pole and a 50amp double pole. The 70 amp double pole seems to be fused onto the silver bar and unremovable. The 50 amp is removable. The 70 died out on us. ...
You probably should not replace a 50 and 75 with a 125. The problem is that although the 125 would have the capacity to supply the same current as the combined 50 and 75, each branch would be provided up to 125 alone, instead of the 50 or 70 that they were allowed before. That is, the 125 won't trip unless both branches exceeded their 50 and 70 amp limits simultaneously. If at any time one branch is drawing very little current, then the other branch would be delivered up to 125 amps. If it is OK that each branch can receive 125 amps alone, then a single 125 would be OK.
And if you have damage to the bus bar, you will have to replace the whole box.
On the other hand, if the existing wires will reach, you might be better off simply replacing all three boxes with one panel.
good luck, be safe
Mar 01, 2011 |