{"product_id":"allen-bradley-440r-n23120-guardmaster-msr127tp-safety-relay","title":"Allen-Bradley 440R-N23120 GuardMaster MSR127TP Safety Relay","description":"\u003ch2\u003eAllen-Bradley 440R-N23120 GuardMaster MSR127TP Safety Relay\u003c\/h2\u003e\n\u003cp\u003eConfigured for dual-channel safety circuit monitoring in industrial control systems, the \u003cstrong\u003eAllen-Bradley 440R-N23120\u003c\/strong\u003e (\u003cstrong\u003e440R-N23120\u003c\/strong\u003e GuardMaster MSR127TP Safety Relay) provides direct safety circuit evaluation. The relay supports cross-fault detection for E-stops, safety gates, and light curtains, with selectable reset functions.\u003c\/p\u003e\n\u003ch3\u003eHardware Specifications\u003c\/h3\u003e\n\u003cfigure\u003e\n\u003ctable\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth\u003eParameter\u003c\/th\u003e\n\u003cth\u003eSpecification\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eModel\u003c\/td\u003e\n\u003ctd\u003e440R-N23120\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBrand\u003c\/td\u003e\n\u003ctd\u003eAllen-Bradley\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eProduct Series\u003c\/td\u003e\n\u003ctd\u003eGuardMaster MSR127TP\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eProduct Type\u003c\/td\u003e\n\u003ctd\u003eSafety Monitoring Relay\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOperating Temp\u003c\/td\u003e\n\u003ctd\u003e-5 deg C to +55 deg C\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePower Consumption\u003c\/td\u003e\n\u003ctd\u003eNot specified in supplied data\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePower Supply Voltage\u003c\/td\u003e\n\u003ctd\u003e24 V AC\/DC\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSafety Contacts\u003c\/td\u003e\n\u003ctd\u003e3 NO\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eAuxiliary Contacts\u003c\/td\u003e\n\u003ctd\u003e1 NC\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSafety Circuit\u003c\/td\u003e\n\u003ctd\u003eDual-channel monitoring with cross-fault detection\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSafety Rating\u003c\/td\u003e\n\u003ctd\u003eUp to Cat 4 \/ SIL CL3 \/ PLe\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eReset Mode\u003c\/td\u003e\n\u003ctd\u003eAutomatic\/Manual or Monitored Manual, selectable\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTerminal Type\u003c\/td\u003e\n\u003ctd\u003eRemovable plug-in screw terminals\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eEnclosure Rating\u003c\/td\u003e\n\u003ctd\u003eIP40, NEMA 1 enclosure; IP20 terminals\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMounting\u003c\/td\u003e\n\u003ctd\u003e35 mm DIN rail\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/figure\u003e\n\u003ch3\u003eAllen-Bradley Safety Circuit Monitoring Characteristics\u003c\/h3\u003e\n\u003cp\u003eThe 440R-N23120 monitors dual-channel safety circuits and detects cross-fault conditions between safety input channels.\u003cbr\u003eFurthermore, the relay supports automatic\/manual reset and monitored manual reset configurations according to circuit requirements.\u003cbr\u003eThe three normally open safety contacts provide switching interfaces for the monitored safety control circuit.\u003cbr\u003eAn additional normally closed auxiliary contact provides a separate status interface for control or diagnostic circuits.\u003cbr\u003eThe removable plug-in screw terminals allow field wiring removal without disconnecting the complete relay housing.\u003cbr\u003eThe 35 mm DIN rail mounting arrangement provides mechanical positioning within standard industrial control enclosures.\u003cbr\u003eThe specified safety capability reaches Cat 4, SIL CL3, and PLe depending on system implementation.\u003c\/p\u003e\n\u003ch3\u003eFrequently Asked Questions (FAQ)\u003c\/h3\u003e\n\u003cp\u003eQ: Does the 440R-N23120 support dual-channel safety monitoring?\u003c\/p\u003e\n\u003cp\u003eA: Yes. The relay monitors two safety channels and provides cross-fault detection between the monitored circuits.\u003c\/p\u003e\n\u003cp\u003eQ: Which reset functions are available on the 440R-N23120?\u003c\/p\u003e\n\u003cp\u003eA: The relay supports selectable Automatic\/Manual reset and Monitored Manual reset configurations.\u003c\/p\u003e\n\u003cp\u003eQ: What terminal and mounting arrangements are specified?\u003c\/p\u003e\n\u003cp\u003eA: The unit uses removable plug-in screw terminals and mounts on a 35 mm DIN rail.\u003c\/p\u003e\n\u003ch3\u003eField Installation Guidelines\u003c\/h3\u003e\n\u003cp\u003eInstall the relay on a suitable 35 mm DIN rail inside an enclosure meeting the specified environmental requirements.\u003cbr\u003eVerify that the 24 V AC\/DC supply is isolated appropriately before connecting power and safety circuit wiring.\u003cbr\u003eWire both safety channels independently according to the approved safety circuit schematic and application architecture.\u003cbr\u003eRoute safety input conductors separately from high-voltage, motor, and high-current switching conductors where practical.\u003cbr\u003eMaintain appropriate separation between safety wiring and electromagnetic noise sources to reduce unintended signal coupling.\u003cbr\u003eConnect cable shields according to the machine grounding design and applicable control-panel wiring standards.\u003cbr\u003eUse the removable terminal blocks to verify conductor identification before inserting the completed terminal assembly.\u003cbr\u003eConfirm the selected reset mode and verify the required reset conditions during commissioning.\u003cbr\u003eTest both safety channels, cross-fault detection, output contacts, and reset behavior before placing equipment into service.\u003cbr\u003eDo not infer missing power consumption, mechanical dimensions, or weight values from enclosure or mounting specifications.\u003c\/p\u003e","brand":"Allen-Bradley","offers":[{"title":"Default Title","offer_id":43874660352090,"sku":"440R-N23120","price":123.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0612\/4601\/3530\/files\/440R-N231141.jpg?v=1787218868","url":"https:\/\/www.plcmasters.com\/products\/allen-bradley-440r-n23120-guardmaster-msr127tp-safety-relay","provider":"PLC Masters Ltd.","version":"1.0","type":"link"}