Product Description:

The EL5101-0090 is an incremental encoder interface terminal produced by Beckhoff within the EL EtherCAT Terminals series. The unit occupies a single I/O slot on an EtherCAT rail and converts quadrature encoder signals into position data that the controller can read in real time. By supplying hardware time stamping through the Distributed Clocks mechanism, the terminal enables synchronized position acquisition across multiple motion axes. This allows the control system to compare encoder feedback across the network with very tight timing. That behavior is useful in applications where multiple encoders must be sampled at the same instant for coordinated positioning or speed monitoring.

The logic side is powered at 24 V DC, while the encoder supply line delivers a regulated 5 V DC for TTL sensors. Power contacts can conduct up to 10 A to downstream terminals, so additional loads can be passed through without separate supply wiring. With a controller scan as short as 100 µs, the module can evaluate encoder edges at rates up to 1 MHz. The internal quadrature decoder performs 4-fold evaluation and supports microincrements down to 1/256 of a count. This helps preserve position accuracy even when pulse trains rise quickly during rapid machine movement. One input channel is available, the sensor output current reaches 0.5 A, and sub-microsecond synchronization is achieved through Distributed Clocks.

The housing measures 24 × 100 × 68 mm and clips onto a DIN rail beside other EL terminals. Its narrow width helps conserve rail space when several terminals are mounted side by side in a control cabinet. An enclosure rating of IP20 confines use to closed panels where higher-level protection is provided, and operation is permitted in ambient humidity up to 95% non-condensing. The position counter and the zero-pulse latch can each be switched between 16/32 bit, so the count width can be matched to the connected encoder.