That is the key right there. If they are supplementary protection then the main runs are branch circuits.Once I traced their listing number I found that UL says they are for supplementary protection.
In that case the OP would have to run same size conductors throughout the run.
225.36 is not circuit specific. It applies to both feeders and branch circuits. In addition, there is the matter of location of the disconnecting means. For that, see 225.32 Exception No. 3.No. A feeder must terminate in a overcurrent protective device per the Art 100 definition, and that has to be a listed disconnecting means, and the key rule is 225.36, the disconnecting means must be suitable for service equipment. This is a branch circuit with supplementary OCPD at each pole.
In that case the OP would have to run same size conductors throughout the run.
#8 Cu 75?C or better is suitable for use on a 50A fused circuit provided it is not derated less than the next smaller standard fuse size and its ampacity is sufficient to carry the calculated load.RUWired I think you may be right.
#8 Cu 75?C or better is suitable for use on a 50A fused circuit provided it is not derated less than the next smaller standard fuse size and its ampacity is sufficient to carry the calculated load.
...So the #6's are upsized...
#8 Cu 75?C or better is suitable for use on a 50A fused circuit provided it is not derated less than the next smaller standard fuse size and its ampacity is sufficient to carry the calculated load.