IEC 61300-3-21:2019

Overview

IEC 61300-3-21:2019 specifies a standardized method to measure switching time and related performance parameters of a fibre optic spatial switch when actuation energy is applied or removed. This third edition is a technical revision that clarifies definitions and diagrams, removes redundant overlap with IEC 60876-1, and generalizes the permitted detection apparatus beyond just oscilloscopes. The document defines measurement setup, apparatus requirements, and timing definitions used to quantify switch dynamic behavior.

Key topics and technical requirements

• Scope of measurement
  • Time-resolved measurement of output optical power referenced to the instant actuation energy is applied or removed.
• Terms and definitions
  • Latency time, rise time, fall time, bounce time, and combined switching time (from isolated→conducting and conducting→isolated) with precise definitions and measurement thresholds (10 % / 90 % levels).
• Apparatus and performance
  • Optical source (S): stable output and appropriate wavelength/spectral width per the relevant specification (see IEC 61300-3-4).
  • Detector (D): fast response - detector response time should be ≤ one-tenth of the rise/fall time to be measured; linearity better than 0.05 dB across expected power; measurement system return loss recommended ≥ 30 dB. Multiple detectors allowed for simultaneous ports.
  • Actuation energy supply (AS): electrical/optical drive rise and fall times should be ≤ one-tenth of the switch rise/fall time; duration long enough to capture bounce behavior for non-latch switches.
  • Data acquisition system (DAS): must record time-dependent optical power synchronized to actuation; oscilloscope or other DAS (including data-logging optical power meters) is acceptable.
  • Termination (T): techniques to suppress reflections (e.g., APC connectors often achieve > 60 dB return loss).
• Procedure and reporting
  • Measurement setup per standard diagrams, synchronized triggering, and specification of environmental and launch conditions. Details to be specified are listed for reproducibility.

Applications and users

• Manufacturers of fibre optic spatial switches validating dynamic performance for product datasheets.
• Test laboratories and QC teams performing acceptance, production or conformance testing.
• System integrators and designers assessing suitability of switches for fast reconfiguration in optical networks, data centers, or sensing systems.
• Procurement and compliance groups requiring standardized test evidence of switching time and related parameters.

Keywords naturally integrated: switching time, performance parameters of a fibre optic spatial switch, actuation energy.

Related standards

• IEC 61300-1 - General and guidance for basic test and measurement procedures
• IEC 61300-3-4 - Attenuation measurements (optical power stability)
• IEC 60876-1 - Definitions for optical switch timing (overlap removed in this edition)