EL1252-0050 BECKHOFF EtherCAT Terminal 2-Channel Digital Input 5 VDC

Product Overview

The EL1252-0050 (EL12520050) is a high-precision, 2-channel digital input terminal designed for ultra-fast signal acquisition within the EtherCAT ecosystem. Operating at a 5 VDC nominal voltage, this module is specifically engineered for applications requiring microsecond-level accuracy, such as high-speed labeling, pulse-width modulation (PWM) analysis, or synchronized motion control in semiconductor and printing industries. By utilizing Distributed Clocks (DC) technology, the EL1252-0050 provides timestamping functionality with a 1 ns resolution, allowing the control system to record exactly when a signal edge occurs regardless of the bus cycle time. This capability is critical for reducing jitter and ensuring deterministic performance in high-speed automated processes where every microsecond impacts product quality and throughput.

Technical Configuration

The EL1252-0050 features a 4-wire connection technology, supporting highly accurate signal detection with a typical input filter of less than 1 microsecond. Its hardware architecture is centered around the "Timestamping" function, which enables the terminal to latch the exact time of the last signal edge. With an internal execution speed of 10 ns and a precision rating of 10 ns (plus input delay), it delivers industry-leading temporal transparency. The terminal is designed for the EtherCAT E-bus system, drawing 90 mA typically, and provides 500 V electrical isolation between the field potential and the internal logic to ensure robust operation in electrically noisy industrial environments.

Technical Specifications

Technical FAQs

How does the timestamping feature in the EL1252-0050 benefit high-speed applications?

The timestamping feature allows the terminal to record the precise moment a digital input transitions (rising or falling edge) with 1 ns resolution. Unlike standard inputs that are polled once per PLC cycle, the EL1252-0050 captures the event time independently of the cycle, enabling the controller to calculate speeds or positions with far greater accuracy than the cycle time would otherwise allow.

What type of wiring is recommended for the 5 VDC signal integrity?

Given the high speed and low voltage (5 VDC) of the signals, it is recommended to use shielded twisted-pair cabling to prevent EMI from inducing false triggers. The terminal supports solid, stranded, and ferrule-terminated conductors ranging from AWG 28 to 14.

Can this terminal be used in hazardous environments?

Yes, the EL1252-0050 is ATEX certified with the marking II 3 G Ex nA IIC T4 Gc, making it suitable for use in Zone 2 explosive atmospheres, provided the installation complies with standard safety housing requirements.

Engineering & Installation Guide

• Distributed Clocks (DC) Synchronization: To leverage the 1 ns timestamp resolution, ensure that the EtherCAT Master is configured to enable Distributed Clocks. The precision of the timestamp is dependent on the DC synchronization of the entire network segment; therefore, use high-quality Cat5e or better cabling for the E-bus connection.

• Signal Debouncing: While the module features a very fast filter (typ. < 1 us), users should be aware that mechanical switches may bounce for several milliseconds. This terminal is best paired with electronic sensors (TTL, CMOS) rather than mechanical contacts to avoid multiple false timestamps.

• Heat Dissipation and Mounting: Install the terminal on a standard 35 mm DIN rail. When mounting multiple high-speed terminals side-by-side, ensure adequate ventilation within the control cabinet to maintain the 0 to +55 Celsius operating range. The use of the double slot and key connection system ensures mechanical stability against vibration (conforming to EN 60068-2-6).