Choose hardware by application, not only by model number. Prefer browsing the catalog? Use Browse Products (Shop). This guide starts with one common industrial need: serial / PLC communication over fiber.
Scenario
Serial / PLC Communication over Fiber
Extend RS-232 / RS-485 / RS-422 serial links over optical fiber for PLC cabinets, wind/solar SCADA, and industrial instruments. This path is for classic serial data fiber terminals — not Ethernet media converters, and not a claim that proprietary fieldbuses convert here automatically.
- RS-485 (primary soft-launch combo)
- RS-232 / RS-422 (ask engineer / later combos)
- Pair required (A↔A)
1 Connect what devices?
Typical ends of the link:
- PLC / RTU / industrial controller with a serial port
- HMI, SCADA gateway, or serial server
- Instrument / inverter / meter that speaks RS-485 (or RS-232 / RS-422)
You need two data fiber terminals (one at each end), matching fiber connectors, and power at both ends. A single unit cannot complete a link.
2 Protocol
In this guide
- RS-485 — multidrop / PLC cabinet (soft-launch primary)
- RS-232 — point-to-point instrument / legacy DTE (confirm with engineer)
- RS-422 — differential serial (confirm with engineer)
Not this guide
- Ethernet copper↔fiber media converters
- CAN-only or DMX512 lighting paths (separate products)
- Any implication that Ethernet or proprietary protocols “convert here” on this combo
If you need those, use Request Quote or Browse Products and describe the ports.
3 Distance & fiber
From the factory datasheet for the recommended industrial mini RS-485 SC terminal:
- Single-mode (SM): standard 20 km; extended 40–100 km available on RFQ
- Multi-mode (MM): about 2 km (optional)
- Connector on this combo: SC — the fiber pair must match SC at both ends
- Wavelength family on sheet: 1310/1550 nm · SM/MM optional
We do not publish longer marketing distances on this page. If your span is beyond 20 km, request the extended optic on RFQ.
4 Interface & power
- Serial: terminal-block RS-485 (1 channel on the industrial mini SKU)
- Optical: SC on the published SKU (FC/ST are sheet options — RFQ if you need them)
- Form: industrial mini, DIN-friendly (~75 × 62 × 28 mm)
- Power: DC5V 1A each end (TX/RX). Industrial units often use P+/P− terminal power. Wording for the combo: DC5V 1A ×2 — included or RFQ (no separate WooCommerce power SKU; factory confirms whether adapters ship in the box)
- Bandwidth on sheet: 180 kbps · plug-and-play · surge / ESD protection
5 Recommended combo (C1)
Primary soft-launch combo · C1
SUN-DFT-IND-RS485-SC × 2 (pair)
Industrial mini RS-485 data fiber terminal (SC). Buy as a pair — one unit at Device A, one at Device B.
- Fiber: single-mode SC fiber (pair needs matching SC)
- Power: DC5V 1A ×2 terminal power — included or RFQ
- Distance: SM 20 km standard; 40–100 km extended on RFQ
When not to use C1: you need RS-232 or RS-422 only → ask an engineer (later combos). You need Ethernet media conversion → not this guide. You need FC/ST optics → RFQ connector option.
Wiring diagram (C1)
Device A — serial — DFT — fiber — DFT — serial — Device B, with power at both ends.
6 Datasheet download + submit confirm
Download the sheet, then send the same scenario + needs + recommended SKU to sales. Prefill is enabled on RFQ (URL query → form fields) and WhatsApp (?text=).
RFQ fields filled: Product/SKU = SUN-DFT-IND-RS485-SC, Quantity = 2, Message = scenario + C1 needs. Edit anything before send. Same desk: sales@optshow.com.
Out of scope / not this guide
- Ethernet media converters (copper Ethernet ↔ fiber)
- CAN-bus or DMX512-only applications (see other data fiber terminals or ask sales)
- RS-232 / RS-422-only builds — tell us on RFQ; additional combos come later
- Invented distances beyond the factory datasheet (standard SM 20 km; extended only on RFQ)
Still unsure? Have an engineer confirm or Browse Products.
Ready to confirm C1?
Pair of SUN-DFT-IND-RS485-SC · SM SC fiber · DC5V 1A ×2 (included or RFQ).