Product Description:

The EPP3204-0002 is a resistance measurement interface manufactured by Beckhoff as part of the EPP EtherCAT P Box Modules series. It is used in industrial automation to collect temperature data from RTDs and potentiometric sensors and to transmit those values over the EtherCAT P network, allowing control systems to place accurate sensing close to a process without local power supplies. By combining power and communication through a single cable, the module simplifies installation on conveyors, presses, and packaging equipment.

The module supports the real-time EtherCAT protocol via two P-coded M8 sockets that act as the bus interface. Four analog input channels are available, so sensors may be wired in 4-wire, 3-wire, or 2-wire configurations depending on accuracy requirements. Each channel is digitized with 16-bit resolution, providing 65,536 discrete counts for resistance conversion. Internal electronics operate from a 24 V DC supply obtained through EtherCAT P and draw only 100 mA, minimizing voltage drop along the trunk line. Physical size is kept to 30 x 126 x 26.5 mm, enabling placement on machine frames next to transducers, while an A-coded M12 connector brings in the field signals.

Measurement integrity is protected by a sensor excitation current limited to 0.5 mA, which reduces self-heating of platinum elements. For a four-wire Pt input, the maximum systematic error is ±0.5 K, helping maintain accurate temperature readings. Resistance values up to 4095 Ω can be processed, and temperature increments are quantized in 0.1 °C steps to match common process demands. The enclosure is molded from PA6 polyamide and sealed with a polyurethane compound against moisture ingress. Two Ø3.5 mm mounting holes for M3 hardware provide secure attachment, and the compact housing supports pass-through daisy-chain cabling.