DIN EN 50557:2012-08

This standard describes automatic reclosing devices for circuit breakers as well as residual current breakers with and without built-in over-current protection (RCBOs and RCCBs) for household and similar uses (ARDs), German Version EN 50557:2011. These devices are intended to reclose main protective devices (hereinafter referred to as "MPD") such as circuit-breakers complying to EN 60898-1 and/or EN 60898-2, RCCBs complying to EN 61008-1 and RCBOs complying to EN 61009-1 after tripping of those devices in order to re-establish continuity of service. In detail, this European Standard applies to the following types of ARDs: - ARDs with assessment means, reclosing only if both the prospective line current and the prospective earth-fault current do not exceed given values; - ARDs with assessment means, reclosing only if the prospective line current does not exceed a given value; - ARDs with assessment means, reclosing only if the prospective earth-fault current does not exceed a given value; - ARDs that reclose without any assessment. The responsible committee is Subcommittee DKE/UK 541.3 "Fehlerstrom-Schutzeinrichtungen" ("Residual current devices") of the DKE (German Commission for Electrical, Electronic and Information Technologies) at DIN and VDE.