EML Selection Guide for Power System-Grade Active Optical Cables

Selecting power system-grade Active Optical Cables (AOCs) requires consideration of fiber type, connector type, transmission speed, and integrated electronics to ensure high reliability and performance.

Fiber Type Selection

• Single-mode fiber (OS1/OS2) is recommended for long-reach applications and high-speed links such as 200G or 400G Ethernet, providing low attenuation and high signal integrity .
• Multimode fiber (OM3/OM4/OM5) is suitable for shorter distances and high-bandwidth applications, using laser-optimized transmitters for 25G, 40G, 100G, and 400G links .
• LED-based OM1/OM2 fibers are generally limited to lower-speed or legacy systems and are not recommended for modern high-speed AOCs .

Connector Types

• LC and MPO connectors are commonly used in AOCs, with LC suitable for single-channel links and MPO for parallel multi-lane connections .
• Polishing types: UPC (Ultra Physical Contact) and APC (Angled Physical Contact) are preferred for high-bandwidth applications. APC connectors reduce return loss and optical reflections, critical for power system reliability .

Active Cable Electronics

• Active Optical Cables integrate optical modules at both ends, eliminating the need for separate transceivers and reducing contamination risk .
• Redriver-based Active Copper Cables (ACC) amplify analog signals using CTLE equalization to compensate for channel loss, suitable for moderate distances .
• Retimer-based Active Electrical Cables (AEC) provide advanced signal reshaping, CDR, and DFE functions, ensuring signal integrity over longer distances or higher-speed links, making them ideal for mission-critical power system applications .

Performance and Reliability Considerations

• Transmission rates: AOCs support 10G, 25G, 40G, 100G, 200G, and 400G Ethernet, with breakout options for multi-lane configurations .
• Power consumption: AOCs are lightweight and low-power, which is advantageous for high-density installations in substations or control centers .
• Environmental compliance: Ensure RoHS-compliant components to meet regulatory and safety standards .
• Testing and certification: Look for products with rigorous testing for signal integrity, EMI resistance, and thermal stability to meet power system-grade reliability requirements .

Summary

When selecting AOCs for power system applications, prioritize fiber type (single-mode for long reach, multimode for short reach), connector type (LC or MPO with UPC/APC polish), and integrated electronics (Redriver or Retimer). Consider transmission speed, environmental compliance, and rigorous testing to ensure high reliability and performance in critical power system networks .