DIN EN 60255-149
; VDE 0435-3149:2014-06
Measuring relays and protection equipment - Part 149: Functional requirements for thermal electrical relays (IEC 60255-149:2013); German version EN 60255-149:2013
Messrelais und Schutzeinrichtungen - Teil 149: Funktionsanforderungen an den thermischen Überlastschutz (IEC 60255-149:2013); Deutsche Fassung EN 60255-149:2013
Overview
This standard specifies minimum requirements for thermal protection relays which protect equipment from thermal damage by measuring the current flowing through the equipment. Moreover, the standard applies to relays with a temperature and a current as input variable. The standard applies to protection relays based on a thermal model with memory function. The test methodologies for verifying performance characteristics of the thermal protection function and accuracy are also included in this standard. The responsible body is DKE/K 434 "Messrelais und Schutzeinrichtungen" ("Measuring relays and protective devices") of the DKE (German Commission for Electrical, Electronic and Information Technologies) at DIN and VDE.