Product Description:

The ELM3002-0000 is an analog input terminal manufactured by Beckhoff as part of the ELM EtherCAT Terminals series. It collects differential voltage signals on two channels and forwards time-synchronized data to the EtherCAT controller, making it suitable for fast closed-loop tasks in industrial automation. Integrated conversion removes the need for remote signal conditioners, and the terminal fits standard DIN-rail assemblies. Power is supplied through the E-bus at 330 mA with a thermal loss of 3 W, while its IP20 enclosure and 707 V DC channel-to-bus insulation protect internal circuitry within control cabinets.

The module digitizes each channel with a resolution of 24-bit, allowing sub-millivolt granularity across the selectable input ranges. A maximum output rate of 20 ksps delivers fresh samples every 50 µs, supporting dynamic measurement tasks such as vibration monitoring. Conversion is performed by a delta-sigma ADC, a topology that filters quantization noise through oversampling and digital decimation for an improved signal-to-noise ratio. The EtherCAT stack can exchange process data every 100 µs, which is the minimum DC cycle time for deterministic operation. Inside the terminal, the converter core clocks at 5.12 Msps, so even after decimation ample samples remain to build averaged values or enable oversampling factors up to 100 without data loss.

The usable input span can be extended up to 30 V full scale or narrowed to a minimum span of 20 mV for sensor-level work, and automatic range switching is configured through TwinCAT. An analog low-pass filter with a cutoff at 5.3 kHz precedes the converter, while additional hardware filtering at 30 kHz blocks higher-frequency interference before it reaches the ADC front end. Two-wire spring terminals simplify field wiring, and the 2-channel architecture supports independent oversampling factors so one input may capture rapid transients while the other tracks slow process variables.