Product Overview
The EL2828 (EL2828) EtherCAT Terminal provides eight electronically protected digital outputs operating at a 24 V DC nominal voltage. Utilizing advanced 2-wire connection technology, this High Density (HD) module is engineered to drive diverse loads, including ohmic, inductive, and capacitive field actuators.
Deployable across heavy industrial environments—such as automotive stamping, automated sorting lines, and food packaging facilities—the module delivers exceptional power routing capability. By supporting up to 2 A per individual channel within a compact 12 mm wide form factor, the terminal eliminates the need for external interposing relays on high-current loads, optimizing control cabinet space and dropping operational failure points to prevent system downtime.
Electronic Protection and Switching Characteristics
The EL2828 features robust internal driver circuitry equipped with short-circuit current limitation (typically restricting faults under 40 A) and native reverse voltage protection. It is uniquely specified to handle inductive breaking energy up to 1.2 J per channel, allowing safe de-energization of solenoids and small DC valves without external flyback diodes.
The physical structure maps an 8-bit output profile directly into the cyclic EtherCAT E-bus process image, completely eliminating manual hardware addressing or software configuration parameters. Its high-efficiency switching speed showcases a typical turn-on time ($T_{ON}$) of 60 µs and a turn-off time ($T_{OFF}$) of 250 µs, facilitating precise timing control for rapid automation sequences.
Technical Specifications
| Parameter |
Specifications |
| Model |
EL2828 |
| Brand |
BECKHOFF |
| Origin |
Germany |
| I/O Technology |
EtherCAT Terminal (E-bus communication) |
| Output Count |
8 outputs |
| Cabling Method |
2-wire connection |
| Nominal Operating Voltage |
24 V DC (-15 % / +20 %) |
| Maximum Output Current |
2 A per channel (Maximum total sum 10 A) |
| Short-Circuit Current |
Typ. less than 40 A |
| Breaking Energy Max |
Less than 1.2 J per channel |
| Switching Performance |
Typ. TON: 60 µs / Typ. TOFF: 250 µs |
| Reverse Voltage Protection |
Yes |
| E-bus Current Draw |
Typ. 110 mA |
| Power Contact Current Draw |
Typ. 15 mA + load current |
| Galvanic Isolation |
500 V (E-bus to field potential) |
| Process Image Bit Width |
Outputs: 8 bits |
| Housing Design |
HD (High Density) housing with status LEDs |
| Dimensions (W x H x D) |
12 mm x 100 mm x 68 mm |
| Weight |
Approx. 70 g |
| Operating Temperature |
-25 to +60 deg C (Vertical installation required) |
| Storage Temperature |
-40 to +85 deg C |
| Protection Rating |
IP20 |
| Compliance Markings |
CE, UL |
Product FAQs
What are the specific advantages of the 2-wire connection technology over standard 1-wire layouts?
The 2-wire architecture provides both the 24 V DC output signal and a dedicated 0 V DC ground return point for each of the eight channels directly on the terminal block face. This design streamlines cabling by allowing field actuators to wire back to the module sequentially, eliminating external ground termination blocks inside the panel.
How does the 10 A sum current limit restrict operation if all channels can pull 2 A?
While any individual channel can source up to 2 A continuously, the internal power contact bus bars have a maximum physical limit of 10 A. This means that if five channels are loaded to their full 2 A capacity ($5 \times 2\text{ A} = 10\text{ A}$), the remaining three channels must remain idle to avoid exceeding the safety threshold.
Does this terminal module utilize Distributed Clocks (DC) for synchronized switching?
No, the EL2828 operates without Distributed Clocks. Output switching commands are updated and executed at the module level on the next immediate frame cycle received from the master EtherCAT controller.
Field Termination Guidelines and Safety Standards
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HD Spring-Cage Cabling Protocols: Open the high-density terminal points using a standard flat-blade technical screwdriver. Strip field wires to a length of 8 to 9 mm. The connection points accommodate solid wire (s) from AWG 28 to 16, stranded wire (st) from AWG 22 to 16, or ferrule-insulated lines (f) from AWG 26 to 19. Ensure ferrules are squarely crimped to secure long-term mechanical grip.
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Mechanical Interlocking and Heat Dissipation: Mount the module vertically on a standard 35 mm DIN rail conforming to EN 60715. Ensure the interlocking double slot and key connection points clip together firmly with adjacent units to establish continuous backplane contact. Vertical orientation is mandatory; running the module under full 10 A load at high ambient temperatures requires active panel airflow to stay within the -25 to +60 deg C operating window.
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Inductive Transient Management: Although the EL2828 features integrated suppression circuitry rated for less than 1.2 J, regularly driving large inductive loads or high-duty-cycle solenoids can cause thermal accumulation. For large field coils, it is highly recommended to mount an external freewheeling diode across the actuator terminals to suppress reverse voltage spikes right at the source.