User manual for the Four Star Electronics FS-OLM2-S PROFIBUS single‑mode fiber link module, covering features, specifications, installation and troubleshooting.
The FS-OLM2‑S is a single‑mode PROFIBUS‑DP fiber link converter that extends RS‑485 based fieldbus communication up to 10 km without loss of speed. It provides electrical isolation, surge protection and supports multiple PROFIBUS variants, MPI, PPI and MODBUS.
The manual details the module’s external hardware, internal block diagram, wiring connections, supported network topologies (point‑to‑point, bus, star, hybrid) and includes a FAQ section addressing common setup questions and ordering information. This manual is written in Chinese.
| Optical ports | Dual ports, single‑fiber bidirectional transmission |
|---|---|
| Fiber type | Single‑mode 9/125, 10/125, 8.3/125 µm |
| Wavelength | 1310 nm / 1550 nm |
| Transmit optical power | -6 dBm |
| Receive optical sensitivity | -18 dBm |
| Maximum fiber distance | 10 km (single‑mode) |
| PROFIBUS‑DP interface | DB9F connector compliant with PROFIBUS‑DP |
| Communication speed | 0 ~ 12 Mbps adaptive |
| Power supply | 9 ~ 40 V DC, 1 W consumption |
| Isolation voltage | 1500 V DC between power, RS‑485 and optical ports |
| Protection rating | IP20 |
| Operating temperature | -40 °C ~ +85 °C |
| Dimensions | 85 mm × 49 mm × 100 mm |
| Weight | 180 g |
FS-OLM2-M uses multimode fiber with a maximum distance of 2 km, while FS-OLM2-S uses single‑mode fiber with a maximum distance of 10 km; all other functions are identical.
The terminal station provides the 5 VDC needed for the pull‑up and pull‑down resistors; if it loses power, the network’s termination resistors are not energized and communication can fail.