What are MIL-DTL-12520 Connectors?

Meet the Connector: MIL-DTL-12520 

Currently inactive for new design, this series of center-lock screw coupling, waterproof, polarized, and multi-contact MIL-spec connectors continues to be available for maintenance of existing military vehicles.

The MIL-DTL-12520 specification is currently inactive for new design but remains available for maintenance of existing military vehicles. This circular, multi-contact, water-resistant electrical connector is designed for demanding ground and shore-based applications. According to its introduction, the specification covers “a series of center-lock screw coupling, waterproof, polarized, multi-contact connectors and accessories” intended primarily for power and control circuits of electronic equipment.

MIL-DTL-12520 connectors are engineered with a center-lock screw coupling mechanism in which a fold-down wing‐blade handle secures the coupling and prevents accidental decoupling under vibration or shock. The housing and shell are polarized, so only correct mating pairings are possible, helping prevent mismating of plugs and receptacles. The spec mandates resistance to ingress of dust, dirt, and water, enabling these connectors to perform in harsh environmental conditions.

Eaton is currently the sole supplier of MIL-DTL-12520.

Design Notes 

Standards:

This military standard can be found at Defense Logistics Agency (DLA) Mil Specification for MIL-DTL-12520 and EverySpec listing for MIL-DTL-12520.

Mounting type or types: Plug and receptacle

Mating cycles: Up to 500

Material specifications: Include gold-over-nickel plated contacts, rugged aluminum alloy or brass bodies, (e.g., mounting nuts in brass ASTM-B36/B121).

Markets and Applications 

Military and aerospace

MIL-DTL-12520 connectors are used in older military, industrial, and ruggedized equipment such as ground vehicles, mobile shelters, field service equipment, and shore‐based installations.

Suppliers 

MIL-DTL-12520 connectors are available from Eaton

Related products 

38999

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