Product Description:

The EL9570-0000 buffer terminal is manufactured by Beckhoff for the EL EtherCAT Terminals series. Within a station, it provides short-term energy storage so that fieldbus couplers, drives, or sensors continue to receive regulated DC power during brief brownouts or high inrush events. By absorbing regenerative energy and compensating load steps, the module improves voltage quality in distributed control cabinets and prevents cycle errors on EtherCAT networks that rely on uninterrupted 50 V logic and actuator supplies.

The unit employs a capacitor buffering topology with an effective capacity of 500 µF, and its load-dependent two-point ballast function connects the storage element only when necessary to control inrush. Running on a nominal bus of 50 V, the power path exhibits less than 10 mΩ of internal resistance, so voltage dips remain limited even while the DC line carries a ripple component of 10 A. This low impedance lets the terminal return energy to the supply during braking events without excessive losses. Because the process image width is 0 bits, the module occupies no address space in the EtherCAT telegram and needs no additional PLC configuration.

Voltage management features include an overvoltage control window of ±2 V around the nominal level; when the DC link exceeds this band, the ballast disengages to prevent capacitor overload. The terminal withstands surge events above 56 V and diverts excess energy through its integrated suppression network. Environmental data specify an IP20 protection class, so the device is intended for installation inside enclosed panels on a 35 mm DIN rail. The housing allows variable mounting orientation, and it can be placed directly next to other EL terminals on the left if no protective earth path is required because the module offers no PE contact. This side-by-side capability simplifies compact EtherCAT node layouts.