The pulsed electrochemical micromachining (PECMM) closes the gap between the normal ECM with gap widths in the middle micrometer range and the EC-nanomachining. As a matter of fact, there is a distinction between the extension of the pulsed electrochemical machining down to smaller gap widths and the enlargement of the machining surface of the EC-nanomachining. The goal is the economical production of large plane microstructures. Due to the necessary application of energy, new requirements have arisen concerning the process energy sources (PES) and their pulse units (PU). This paper will show the influence of the feeder of the gap on the shape of the voltage impulses appearing at the gap, and which repercussions the gap may have on the PES. Furthermore, it is of interest to capture the electrical process values (e.g. gap current) very precisely, to react fast on abrupt process changes. Two circuit concepts of pulse units have been developed. Both allow a process control in the relevant parameter range, providing a gap current signal remaining true to shape.
