Safety system used with power electronics of frequency converter includes multi-channel inputs and outputs with reception of shutdown signal from previous safety stages

摘要

An at least two-channel output (A20, C20) relays a shutdown signal (c20a, c20b, a20a, a20b) to a further signal stage (A, B). An at least two-channel input (A10, C10) receives a switch-off signal from a previous safety stage (C, B). This forms an electrical ring circuit of at least two, preferably three or more safety circuits or safety stages (C, B). An independent claim is included for the corresponding method.