Overview
ISO 27027:2014 defines general performance requirements and test methods for solid-state remote power controllers (SSPC) used in aerospace electrical power systems. The standard covers functional definitions, electrical characteristics, performance criteria (including arc fault detection), and quality assurance provisions for SSPCs - devices that use solid-state switching and associated circuitry to control, protect and report on power outputs in aircraft and space vehicles.
Key topics and requirements
- Scope and definitions: Clear definitions for SSPC functions such as on/off, trip, reset, current limiting, peak let‑through current, reverse current, and arc‑fault types (parallel and series).
- Electrical characteristics: Requirements for operation across supply voltage variations and ability to control diverse load types; measured under specified ambient test conditions.
- Performance tests: Methods for verifying control signal thresholds, turn‑on/turn‑off times, soft on/off (load voltage rise/fall), isolation, voltage drop, off‑state leakage/output voltage, and power dissipation.
- Overload and protection behavior:
- Current limiting and trip curve compliance - SSPC must meet specified trip-time vs current characteristics and limit peak let‑through current.
- Trip‑free behavior - once tripped by overload or arc fault, device remains tripped until reset.
- Arc fault detection: Explicit test methods and pass/fail criteria for detecting and tripping on parallel and series arc faults, while avoiding nuisance trips from normal loads or faults on other circuits.
- Special switching modes: Zero‑voltage turn‑on / zero‑current turn‑off for AC devices, soft on/off profiles, and reverse‑current tolerance.
- Environmental and test conditions: Electrical tests performed with the SSPC mounted on a heat sink and within specified temperature, humidity and pressure ranges.
Applications and who should use it
ISO 27027:2014 is relevant to:
- Aerospace electrical system designers and avionics engineers specifying or integrating SSPCs.
- Manufacturers of solid‑state remote power controllers seeking product design and test guidance.
- Qualification and test laboratories performing performance and compliance verification.
- Aircraft OEMs, system integrators and procurement teams creating component requirements and supplier contracts.
Practical uses include product specification, type‑approval testing, design validation for arc‑fault mitigation, and ensuring interoperability with aircraft electrical architectures.
Related standards
- ISO 1540 - Aerospace - Characteristics of aircraft electrical systems (referenced for supply variation).
- ISO 7137 - Aircraft - Environmental conditions and test procedures for airborne equipment (recommended for environmental tests).
- ISO/IEC Directives referenced for document development and maintenance.
Keywords: ISO 27027:2014, SSPC, solid‑state remote power controller, aerospace electrical power systems, arc fault detection, trip curve, current limiting, test methods.