Select SFP
SFP stands for Small Form-factor Pluggable. It is a pluggable transceiver module for optical or electrical network connections.
Basics: Data rate, 100BaseX and SGMII
100BaseX is a fast Ethernet standard with a fixed transmission rate of 100 Mbit/s.
SGMII stands for Serial Gigabit Media Independent Interface. The interface is designed for Gbit Ethernet and can also map lower net data rates such as 100 Mbit/s or 10 Mbit/s via symbol repetitions.
SFP+ modules must not be used because SFP+ is intended for data rates above 1 Gbit/s.
Functionality of the CU1521-0020 with SFP
HW | FW | Functionality |
|---|---|---|
00-01 | 01 | Only use in pairs CU1521-0020 <-> CU1521-0020, with identical 1 Gbit SFP on both sides |
00-01 | 02-04 | Can also be used against EK1501, CU1521 etc., with 100 Mbit SFP |
02 | From 06 | Identification of the plugged SFP; diagnosis of the SFP EtherCAT line; setting the Ethernet encoding |
The CU1521-0020 communicates via SFP with 100BaseX if an SFP type "100 Mbit" is plugged in and the Ethernet encoding has not been changed.
The CU1521-0020 communicates via SFP with SGMII 1 Gbit if an SFP type "1 Gbit" is plugged in and the Ethernet encoding has not been changed.
Checklist for the choice of SFP
Test point | Why is it important? | Measure |
|---|---|---|
Data rate / Encoding | SFP and remote station must support the same procedure. | 100 Mbit SFP for 100BaseX; 1 Gbit SFP for SGMII. From HW02 Encoding check and set in CoE if necessary. |
Wavelength | The transmitter on one side must match the receive wavelength of the remote station. | Compare SFP data sheets from both sides. |
Fiber type | Single-mode and multi-mode routes are not interchangeable. | Match the fiber type of the system with the SFP type. |
BiDi pairing | Two identical BiDi-SFPs do not form a correct route. | Use complementary pair. |
Current consumption / power loss | The SFP heats the appliance and must not exceed the power budget. | Evaluate the data sheet value at Approved ambient temperature range and thermal power budget. |
Temperature class | Commercial SFPs can warn earlier or fail. | Industrial-SFP with at least 85°C recommended. |
EtherCAT suitability | Link control and timing must not be affected. | Preferably use qualified SFPs. |
 | Note on third-party SFP The SFP is not sold by Beckhoff as accessories and is not part of the scope of supply. Beckhoff cannot provide a functional guarantee and compatibility with all SFPs available worldwide. |
SFP qualified by Beckhoff (status 2025-05) | Name |
|---|---|
Single-mode 100 Mbit | Optomedia PT1-S1-4203L |
Multi-mode 100 Mbit | Optomedia PT1-M4-4023L |
Bidirectional 1 Gbit | FS 36888 1000BASE-BX-D BiDi SFP 1550 nm-TX/1310 nm-RX 40 km LC (2024) |
Bidirectional 1 Gbit | FS 36889 1000BASE-BX-U BiDi SFP 1310 nm-TX/1550 nm-RX 40 km LC (2024) |