ISO 1509-2024 PDF

Full title and description

ISO 1509:2024 — General purpose push-pull three-pole circuit-breakers for aircraft — Performance requirements. This international standard specifies performance, construction and test requirements for push‑pull, three‑pole, trip‑free circuit‑breakers with inverse time/current characteristics, intended for use in nominal 115 V / 200 V three‑phase 400 Hz a.c. aircraft electrical circuits (normal ratings up to and including 35 A).

Abstract

This document defines functional and environmental performance requirements, dimensional and mounting guidance, trip‑free operation and time/current characteristic tests, electrical and mechanical tests (including dielectric, insulation, holding current and calibration tests), and requirements to ensure reliable operation at specified temperatures and altitudes for push‑pull three‑pole circuit‑breakers used on aircraft.

General information

• Status: Published.
• Publication date: April 2024 (Edition 2, published 2024-04).
• Publisher: International Organization for Standardization (ISO).
• ICS / categories: 49.060 (aerospace engineering / aircraft electrical equipment).
• Edition / version: Edition 2 (2024).
• Number of pages: 14.

Scope

Specifies performance requirements for push‑pull, three‑pole, trip‑free circuit‑breakers having an inverse time/current characteristic with normal ratings up to and including 35 A for use in nominal 115 V / 200 V three‑phase 400 Hz a.c. circuits on aircraft. The standard covers design, operation, mounting, environmental capability (temperature and altitude), electrical and mechanical test methods and acceptance criteria.

Key topics and requirements

• Trip‑free push‑pull operation and manual actuation (single button: push to make, pull to break) with clear open/closed indication.
• Inverse time/current characteristic for overload protection up to 35 A and prohibition of automatic re‑close after tripping.
• Ambient temperature and altitude capability (typical ranges include −55 °C to +70 °C or −55 °C to +125 °C and altitude suitability to at least 22 000 m as specified).
• Construction and dimension guidance (through‑panel mounting, single‑hole fixing preferred; envelope and fixing dimensions referenced to ISO 1033).
• Electrical and mechanical tests: time/current characteristic tests, voltage drop and dielectric/insulation tests, holding current and calibration tests, mechanical endurance and contact‑making/breaking timing (contacts to operate within defined ms tolerances).
• Requirements for synchronized operation of the three poles (contacts to open/close together; difference typically limited to a few milliseconds).

Typical use and users

Used by aircraft equipment designers, avionics and electrical systems engineers, component manufacturers, testing laboratories, certification bodies and maintenance organizations that design, specify, manufacture, test or approve push‑pull three‑pole circuit‑breakers for use in aircraft electrical installations. It is referenced for procurement specifications, design verification and qualification testing.

Related standards

Normative and related references include standards addressing component dimensions and aircraft conductors, for example ISO 1033 (envelope and fixing dimensions) and ISO 2635 (conductors for aircraft electrical cables) which are cited in normative references. The standard is prepared under ISO/TC 20/SC 1 (aircraft electrical equipment). Users should also consider applicable industry or regulatory specifications for aircraft equipment qualification and installation.

Keywords

circuit‑breaker, push‑pull, three‑pole, trip‑free, aircraft, performance requirements, inverse time characteristic, 400 Hz, 115 V, 200 V, through‑panel mounting, ISO 1509:2024.

FAQ

Q: What is this standard?

A: ISO 1509:2024 is an international standard that specifies performance, construction and test requirements for general‑purpose push‑pull three‑pole circuit‑breakers used in aircraft electrical systems.

Q: What does it cover?

A: It covers functional requirements (trip‑free operation, inverse time/current characteristics), design and mounting guidance, environmental capability (temperature and altitude), and required electrical and mechanical tests and acceptance criteria for circuit‑breakers with normal ratings up to 35 A in 115/200 V, 400 Hz three‑phase aircraft circuits.

Q: Who typically uses it?

A: Avionics and aircraft electrical designers, circuit‑breaker manufacturers, test laboratories, certification authorities and maintenance/overhaul organizations use this standard for specification, design verification, testing and acceptance.

Q: Is it current or superseded?

A: Current — ISO 1509:2024 (Edition 2) was published in April 2024 and replaces the earlier ISO 1509:1973 edition.

Q: Is it part of a series?

A: It is a standalone product standard under the remit of ISO/TC 20/SC 1 (aircraft electrical equipment). It references other ISO documents for dimensions and related technical details (for example ISO 1033) and should be considered alongside other aircraft component and installation standards.

Q: What are the key keywords?

A: Circuit‑breaker, push‑pull, three‑pole, trip‑free, aircraft, inverse time characteristic, 400 Hz, panel mounting, performance tests.