Product Description:

The ELM3604-0002 is an analog measurement terminal manufactured by Beckhoff within the ELM EtherCAT Terminals series. Mounted on a DIN rail beside other I/O, the unit provides fast voltage acquisition for control loops and condition monitoring in industrial automation. By streaming digitized data directly onto the EtherCAT network, the module removes the need for separate stand-alone data loggers and integrates precision measurement into the same real-time fieldbus that supports motion, safety, and process control nodes.

The terminal employs delta-sigma conversion and runs its front end at 5.12 Msps, then decimates the stream to an effective 20 ksps for transmission on the bus. A 24-bit word length delivers high dynamic range, while the internal ADC filter falls to -3 dB at 5.3 kHz, limiting high-frequency noise before processing. The input stage has 4 single-ended channels. Wiring follows the 2-wire principle, and each signal enters through a shielded BNC connector, which helps maintain controlled impedance and reduce external interference. Ahead of the converter, an additional analog low-pass filter with a -3 dB point at 30 kHz attenuates alias components. The device accepts full-scale data in 150 µs after power-up, and it tolerates ambient relative humidity up to 95% when installed in a control cabinet.

In network operation, the terminal synchronizes to the EtherCAT distributed clocks. The time window between reference updates can be as short as 100 µs and as long as 10 ms, allowing it to align with drive-based sampling tasks or slower supervisory scans. For application cycles coordinated by the Sync Manager, user programs may select periods down to 200 µs or extend them to 100 ms. All electronics reside in a compact housing rated at IP20, so installation is restricted to enclosed panels without additional sealing.