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SELECTED MACHINE SAFEGUARDINGTERMINOLOGYAuthorized Output: an output from a safety controller’spositive-guided relays (used to “authorize” or “enable” amachine’s start circuit when safety system conditionsexist). Also known as “safety output.”Automatic Reset: a safety controller reset circuit thatautomatically resets the safety controller when safesystem conditions (no system faults) exist. A manualreset button is optional.Auxiliary output: a non-safety related contact closureor semiconductor output primarily used for signalingcomponent or system status to a PLC, audible alarmor visual indicator (such as a stack light). Also called a“signaling contact” or “auxiliary monitoring contact”.ANSI (American National Standards Institute): anassociation of industry representatives who, workingtogether, develop safety and other technical standards.Auxiliary monitoring contact: See “auxiliary output”.BG (Berufgenossenschaft): an independent Germaninsurance agency whose legislative armrecommends industry safety practices.One of many “notified bodies” authorizedto certify that safety products comply withall relevant standards.CE (Conformité Europeéne) mark: a symbol (CE)applied to finished products and machinery indicatingit meets all applicable European Directives. For electricaland electronic “finished products”, such as a safety relaymodule, these include the Low VoltageDirective and, where relevant, theElectromagnetic Compatibility (EMC)Directive.Coded-Magnet Sensor: a two-piece position sensorconsisting of an array of reed switches and a multiplemagnet array-actuating element. Such devices will onlydeliver an output signal when the reed switch elementis in the presence of a matched, multiple-magneticfield array. Coded-magnet sensors cannot be actuatedusing a simple magnet. Hence they are far more difficultto defeat/bypass than a simple magnetic switch orproximity sensor.Control Reliability: A term applied to safety devices orsystems which are designed constructed and installedsuch that the failure of a single component within thedevice or system does not prevent normal machinestopping action from taking place…but does410 prevent a successive machine cycle frombeing initiated.CSA (Canadian Standards Association): an independentCanadian testing and standards-makingorganization similar to UnderwritersLaboratories (UL) in the U.S. “CSA-certified”products meet relevant CSA electrical andsafety standards.Declaration of Conformity: a manufacturer’s self-certifieddocument, signed by a highly-positioned technicalmanager, which lists all the Standards and Directives towhich a product conforms. A Declaration of Conformityis mandatory for all CE-marked products, and formachine components which, if they fail, could lead to adangerous or hazardous situation on a machine.Defined Area: a predetermined area scanned by a lightbeam within which the presence of an opaque object ofspecified minimum size will result in the generation of acontrol signal.Direct-Action Contacts: See “positive-break” contacts.Diverse Redundancy: the use of different componentsand/or different microprocessor instruction sets writtenby different programmers in the design and constructionof redundant components/circuits. Its purpose is toincrease system reliability by minimizing the possibilityof common-mode failure (the failure of like componentsused in redundant circuits).Dual-Channel Safety System: a safety control systemcharacterized by two inputs; each connected to one oftwo independent safety circuits. Dual-channel systemsare typically capable of detecting interconnection wiringfaults such as open circuits, short-circuits and groundfaults. As such they provide a higher level of safety thansingle-channel systems.E-Stop (Emergency Stop): the stopping of a machineby actuation of an “emergency stop” switch (such as asafety interlock switch, emergency push button switch,rope-pull switch, foot switch, or other actuating device.European Machinery Directive (EMD) 98/392/EEC:a set of machine safety design requirements which mustbe satisfied to meet the Essential Health and Safetystandards established by the European EconomicCommunity. This Directive, and other relevant EuropeanDirectives (such as the Low Voltage Directive, EMCDirective, et al) must be satisfied for the machine tobear the CE mark.