One legacy order code buys the whole 120 VAC MC-50a reversing assembly: MC-50A/R-AC120V, rated 40 HP at 440–480 V
Asked:
“Find LS Electric Metasol 50 amp reversing contactor assembly part numbers and 120 VAC coil mechanical interlock compatible with MC-50a at 460 V”
Cross-referenced 21 candidate part identifiers from 12 independent hosts — LS Electric catalogs, Altech/Mouser catalog mirrors, FactoryMation, Wolf Automation, Voomi and other distributors — covering complete reversing assemblies, mechanical interlocks, reversing wiring kits, and individual 120 VAC-coil MC-50a contactors. Note: 460 V is the switched three-phase power circuit; 120 VAC is the control-coil voltage. They are not conflicting specifications.
The reversing system: two MC-50a contactors, one interlock, one wire kit, one 460 V motor
Best complete order: MC-50A/R-AC120V — 120 VAC 50/60 Hz reversing assembly of two MC-50A contactors, mechanical interlock and reversing wire set; 70 A continuous, 40 HP three-phase at 440–480 V. altechcorp.com
Build-from-parts interlock: UR-02 (2 NC), listed for MC-9B through MC-100A — therefore MC-50a; current numeric cross-reference 83411634001. voomisupply.com
Reversing wire kit: UW-63 is explicitly listed for MC-50A/MC-65A frames; the current numeric MC-50a reversing wiring-kit listing is 76671632003. wolfautomation.com
Individual 120 VAC contactors: MC-50A-22-AC120 (50 A, 2 NO + 2 NC, 40 HP / 52 A at 460 V) and modern numeric listings 1338000500, 1380001300 and 1380012900, where suffix code K7 denotes the 120 VAC coil. factorymation.com
Recommended order table — all 21 cross-referenced identifiers
Part number
Role
Coil / spec
Rating at 460–480 V
MC-50a fit
Source
Rows tagged recommended are the true 50 A / MC-50a parts for this reversing system. Rows tagged not for this BOM are lower-current or different-frame catches (e.g. 1316000500 is a 9 A 18AF contactor, 1340012900 is a 75 A unit) or generic family labels — UR and UW are newer catalog-family labels, not exact order identifiers like UR-02 and UW-63.
Compatibility and caveats
MC-50A/R-AC120V, UR-02 and UW-63 are legacy-style catalog identifiers from Altech/Mouser-mirrored LS catalogs — confirm current availability with the supplier before ordering.
Prefer official LS Electric material for electrical ratings and compatibility; use distributor pages for orderable numeric cross-references (83411634001 for UR-02, 76671632003 for the MC-50a reversing wire kit).
Modern numeric listings (1338000500 / MC50A-30-00-K7-S-E, 1380001300 / MC50A-30-00-K7-L-E, 1380012900 / MC50A-30-22-K7-L-E) are alternatives to the legacy codes; not every suffix is interchangeable — verify auxiliary-contact and mounting variants against your panel design.
460 V in the ratings refers to the switched three-phase motor circuit (40 HP, ~52 A per FactoryMation); the 120 VAC figure is the coil control voltage.
Safety: this is product research, not wiring instructions. Reversing starters require correct electrical interlocking in the control circuit, overload protection, short-circuit protection, enclosure and SCCR coordination, and installation by a qualified electrician.
Product research from 21 cross-referenced part identifiers (consolidated candidate table) plus 50 supporting catalog-evidence rows across LS Electric, Altech/Mouser mirrors, FactoryMation, Wolf Automation, Voomi and other distributors. Ratings quote each source page verbatim; "rating at 460–480 V" is the three-phase motor load rating, coil voltage is the 120 VAC control input. Long compatibility notes trimmed for space; every row links its source.