## Common ground
All options refer to optical switches—devices that use light to control the flow of signals or power.
## Options at a glance
**8517.62 – Data transmission switching**
- **Defining trait:** Designed specifically for routing data signals in telecommunications or networking systems.
- **Typical examples:** Optical transceivers, fiber-optic network switches, data center signal routers.
- **Best fit when:** The switch is used to manage high-speed digital data flow in IT infrastructure.
**8536.50 – Electrical circuit switching**
- **Defining trait:** Uses optical technology to control electrical circuits (e.g., isolating or connecting power paths).
- **Typical examples:** Opto-isolators, solid-state relays with optical input, industrial control switches.
- **Best fit when:** The device controls electrical power or signals in a circuit using light for isolation.
**9013.80 – Signal routing with optical fibers**
- **Defining trait:** Contains optical fibers and is used to route optical signals directly within fiber optic systems.
- **Typical examples:** Fiber patch panels, wavelength-selective switches (WSS), optical cross-connects.
- **Best fit when:** The switch physically manages light signals through fiber cables in telecom or data networks.
## Key differences
| Feature | 8517.62 | 8536.50 | 9013.80 |
|-----------------------|--------------------------|----------------------------|------------------------------|
| Primary function | Data signal switching | Electrical circuit control | Optical signal routing via fiber |
| Core technology | Optoelectronic data links| Optical isolation | Integrated optical fibers |
| Typical application | IT/data networks | Industrial/automation | Telecom/fiber infrastructure |
## How to choose
- Does it route digital data in a network? → 8517.62
- Is it used to isolate or switch electrical circuits with light? → 8536.50
- Does it contain optical fibers and manage light signals directly? → 9013.80
## Overlaps & pitfalls
- A device that routes data via fiber (e.g., in a data center) could fit both 8517.62 and 9013.80. The key is whether it’s primarily for *data transmission* (8517.62) or *fiber-based signal routing* (9013.80).
- If the product uses optical isolation to control electrical circuits, it fits 8536.50 — even if it’s in a network device.
- **No clear priority**: Choose based on the product’s MAIN function. If unsure, prioritize the most specific use case (e.g., fiber integration → 9013.80)