Ochrona przeciwporażeniowa instalacji napędowych z napięciowymi przemiennikami częstotliwości zasilanymi z sieci TN-S do 1 kV

Voltage frequency converter for driving systems is complicated power electronic device, in aspect of assurance proper protections against electric shock. Increases it large difficulties at designing and building of it power supply system. In this paper author passed analysis of supply power system with drive VFC in rules of electric shock protection, according to norm IEC 60364. One proposed realization of additional shock protection in typical installation, is only by use quick disconnection of VFC from power supply by fuses and proper drive equipments connection to the earth. Proper appointment of impedance loop of short-circuit on VFC power supply connectors has basic meaning for selection value of input quick fuses. Using connections to earth of VFC protective connector PE with little impedance for high frequency waves, indeed limits disturbances about radio frequencies emitted to environment. In normal work of these drive systems accrues high frequencies currents which dependents from VFC configuration and conditions of installation work. These currents make impossible usage high sensitive RCD switches. In supplement safety protection only, as protection against fire, author allows usage of RCD switches type A with earth currents from 100 -500mA. This paper can have controversial discuss because positions different specialists are here strongly not uniform.