ISO 461-2:1985

Overview

ISO 461-2:1985 - Aircraft - Connectors for ground electrical supplies - Part 2: Dimensions specifies the physical dimensions and tolerances for aircraft ground-power connectors. It defines size, mounting and envelope limits for the six connector styles used to transfer ground electrical power to aircraft: Style 1A/1B (28 V DC), Style 2A/2B (112 V DC) and Style 3A/3B (200 V AC, 400 Hz, 3‑phase). Part 2 complements ISO 461-1, which covers design, performance and test requirements.

Key Topics

• Connector styles covered: aircraft fixed connectors (A) and ground supply free connectors (B) for 28 V DC, 112 V DC and 200 V AC (400 Hz, 3‑phase).
• Dimensional drawings and tolerances: metric and inch values are shown in figures with mounting dimensions, envelope limits and maximum projections.
• Contact engagement: specification that the length of engagement between male and female contacts must not be affected by mounting method.
• Contact fit and electrical performance: male/female fit must limit voltage drop per ISO 461-1 requirements; individual female contacts allowed a maximum radial movement of 0.5 mm.
• Mounting and sealing: provisions for pressurized mountings to allow sealed joints where the connector shroud passes through aircraft structure.
• Polarity and control contacts: notes on use of the control male contact at positive polarity and at the voltage of the main positive contact.
• Reference to Part 1: ISO 461-1 provides the related design, performance and test criteria that work together with dimensional requirements.

Applications

ISO 461-2 is used to ensure mechanical interchangeability, safe connection and consistent mounting of ground power connectors across aircraft and ground support equipment. Typical users include:

• Aircraft OEMs and systems integrators specifying connector interfaces.
• Ground support equipment (GSE) manufacturers designing supply plugs and sockets.
• MRO and airport operations teams ensuring compatibility with aircraft inlet/ground power units.
• Connector designers and test labs verifying conformity to dimensional and tolerance requirements.
• Regulatory and procurement teams referencing standardized interface specifications for spares and retrofits.

Related Standards

• ISO 461-1 - Aircraft - Connectors for ground electrical supplies - Part 1: Design, performance and test requirements (referenced by ISO 461-2).

Keywords: ISO 461-2:1985, aircraft connectors, ground electrical supplies, connector dimensions, 28 V DC, 112 V DC, 200 V AC, 400 Hz, aircraft fixed connector, ground supply free connector, mounting dimensions, electrical connector standards.