The EK1818 EtherCAT Coupler links an EtherCAT network (100BASE‑TX) to a local station of EtherCAT Terminals (ELxxxx) and additionally provides a small set of onboard digital I/Os. It converts incoming EtherCAT telegrams to the internal E‑bus format and automatically detects and maps attached terminals (up to 65,534 EtherCAT Terminals per network) into the controller’s process image, making configuration straightforward in TwinCAT or other EtherCAT masters.
Integrated I/O includes 8 digital inputs and 4 digital outputs at 24 V DC. The inputs comply with EN 61131‑2 type 1/3, accept “0” from −3…+5 V and “1” from 11…30 V (type 3), have a typical input current of 3 mA and a fixed 3 ms input filter, making them suitable for standard sensors and pushbuttons. The outputs support ohmic, inductive and lamp loads, provide up to 0.5 A per channel (short‑circuit proof, typical short‑circuit current < 2 A), include reverse polarity protection, and can handle breaking energy < 150 mJ per channel, with typical switching times of TON ≈ 60 µs and TOFF ≈ 300 µs.
For networking, the coupler has two RJ45 ports: the upper port connects to the EtherCAT master, while the lower port allows daisy‑chaining additional EtherCAT devices or terminals within the same segment and supports line or star topologies, optionally with EtherCAT junctions. Data is transferred over shielded Cat.5 (or better) Ethernet cables up to 100 m between stations, at 100 Mbit/s with approximately 1 µs latency through the coupler.
The EK1818 is powered from a 24 V DC system supply (Us) and a separate 24 V DC field supply (Up), both wired directly at the coupler. It can supply up to 5 V, 1 A on the E‑bus to feed attached EtherCAT Terminals, and forwards the field supply via power contacts with up to 10 A to downstream I/O modules; if more E‑bus current is needed, power feed terminals (e.g. EL9410) must be added. Typical current consumption is 40 mA + load from Up and 100 mA + (Σ E‑bus current / 4) from Us, with 500 V isolation between power contacts/supply/Ethernet and between E‑bus and field potential.
The module is housed in a 44 × 100 × 67 mm HD polycarbonate housing with integrated signal LEDs, suitable for DIN‑rail mounting (35 mm EN 60715) and side‑by‑side connection via Beckhoff’s double‑slot/key system. It carries an IP20 protection rating, operates from −25 to +60 °C with up to 95% non‑condensing humidity, and meets EN 60068 shock/vibration and EN 61000‑6‑2 / EN 61000‑6‑4 EMC standards. The EK1818 is CE and UL approved and is supplied as a regularly available product in Beckhoff’s EtherCAT I/O range.
Key Specifications
