Product Description:

The EL3681-0030 analog input terminal is manufactured by Beckhoff as part of the EL EtherCAT Terminals series. It captures single-channel voltage or current signals and translates them into deterministic EtherCAT process data for programmable controllers. Placing this module directly on the I/O strand shortens analog cable runs and supports modular machine topologies in industrial automation.

The EL3681-0030 offers one electrically isolated measurement channel that can be parameterized for either voltage or current. Supported voltage spans of 300 mV, 3 V, 30 V, and 300 V cover low-level sensor outputs as well as mains-related signals. Selectable current ranges of 100 mA, 1 A, and 10 A address shunt or Rogowski transducers. Raw conversion uses a 32-bit data / 16-bit control architecture, and each sample is quantized with an 18-bit + sign resolution. Under reference conditions, the absolute deviation remains within a 0.01% measurement error. Electrical isolation is rated up to 300 V AC/DC and is reinforced by a 480 V AC dielectric strength barrier between the field side and the EtherCAT side. The module draws 150 mA from the E-bus for its ADC, scaling switches, and LEDs.

For current measurements, the terminal imposes channel-dependent input resistances of 3 mΩ, 0.2 Ω, or 12.5 MΩ, which helps limit power loss while preserving accuracy. Continuous load capability matches the highest measurement band, and transient peaks up to 30 A for 1 s are tolerated without damage during short inrush events. The sequence controller can request fresh data every 62.5 ms, which supports slower energy-monitoring tasks without overloading network bandwidth. The unit is externally calibrated, so traceability is maintained without on-site adjustment. Its housing measures 12 mm × 100 mm × 68 mm, allowing multiple terminals to be lined up on the DIN rail without increasing enclosure depth.