I recently had a MBE 1224 100BTF Service panel (Meter/breakers) installed. This is has a 100A factory installed main breaker. The electrician was supposed to install a 125 Amp service to match the previous Zinsco panel. He then replaced the factory breaker with a 125 Amp breaker. Eaton has confirmed that everything but the breaker is rated for 125 Amp, but replacing the breaker voids the warranty and UL rating. They claim that the aluminum wires cannot be reused and will not sell replacement wires (meter to breaker) because it must be bent to NEC specs and factory installed. Is the main breaker replacement without replacing the wires considered acceptable? I don't think that there is enough slack to trim the wire back for a new connection. Could new wires be replaced in the field? Are these breakers typically replaced in the field? Would a city inspector fail this installation if the breaker was replaced on this panel. I see no instructions on the panel PUD for replacement. Thanks
NEC 110.3(B) Equipment must be used according to labeling and instructions.
This is because the labeling and instructions are approved by UL as part of approving the equipment. NEC 110.2 requires use of approved equipment.
So... The question of changing the breaker is decided entirely by the labeling and instructions. Either they say it can be done and prescribe particular part numbers and a procedure to do so, or they do not.
And if they do, and 110.3 was followed, then the warranty should be good.