Posted to News on 28th Aug 2007, 08:33
Busbars enhance uprated miniature circuit breakers
Rockwell Automation is extending the Allen-Bradley Bulletin 1489 range of miniature circuit breakers with accessories. The expanded Bulletin 1489 range now also includes busbars to provide simple and flexible connectivity in control panels. With its improved ratings the 1489 miniature circuit breakers can now offer a premium solution from a globally accepted product.
The busbars are offered in three lengths to provide six, twelve or eighteen connection poles, with protective covers available for any unused poles. The incoming line terminal allows multi-phase power to be mounted on the same circuit breaker, with the correct spacing requirements fulfilled. For increased versatility, as well as standard line terminal connections, the busbars provide the option of ring terminal connections for easy connection of the load.
Connectivity can be readily expanded by joining up to three busbars together using overlap joints, enabling connection of up to 52 circuit breakers on a single-phase busbar, up to 25 on a two-phase busbar and up to 16 on a three-phase busbar. The standard protective covers for unused connections also cover overlapped unused connections on expanded busbars.
The expanded ratings of the 1489 miniature circuit breakers cover two additional areas. Previously, the 25A version carried a 240V AC maximum rating for UL/CSA applications. The newly manufactured 25A devices now have a maximum voltage rating of 480Y/277V AC. The 1489 miniature circuit breakers are also now rated for DC (previous versions only carried an AC voltage rating); newly manufactured devices have a DC rating of 48V DC (one pole) and 96V DC (two poles in series). Products carrying the new ratings are marked accordingly.
