{"product_id":"allen-bradley-1746-nr8-c-rtd-resistance-input-module","title":"Allen-Bradley 1746-NR8\/C RTD\/Resistance Input Module","description":"\u003ch1\u003eAllen-Bradley 1746-NR8\/C RTD\/Resistance Input Module\u003c\/h1\u003e\n\u003cp\u003eConfigured for RTD signal acquisition and resistance measurement in SLC 500 I\/O backplane systems, the\u003cspan\u003e \u003c\/span\u003e\u003cstrong\u003eAllen-Bradley 1746-NR8\/C\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003e(\u003cstrong\u003e1746-NR8\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003eRTD\/Resistance input module) provides direct electrical conversion of low-level temperature resistance signals into backplane digital data. The module operates across an 8-channel input architecture with sigma-delta conversion and internal filtering for sensor-level signal conditioning.\u003c\/p\u003e\n\u003cp\u003eThe unit is designed for RTD sensor interfacing including Pt and Ni element types, performing multi-channel temperature acquisition through the SLC 500 chassis communication bus.\u003c\/p\u003e\n\u003ch3\u003eSuffix Breakdown \u0026amp; Model Matrix\u003c\/h3\u003e\n\u003cul class=\"list-paddingleft-2\"\u003e\n\u003cli\u003e\n\u003cp\u003e1746: SLC 500 I\/O platform\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eNR8: 8-channel RTD\/Resistance input function block\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eC: Revision \/ series suffix level\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eHardware Specifications\u003c\/h3\u003e\n\u003ctable class=\"w-fit min-w-(--thread-content-width)\"\u003e\n\u003cthead\u003e\n\u003ctr class=\"firstRow\"\u003e\n\u003cth class=\"last:pe-10\"\u003eParameter\u003c\/th\u003e\n\u003cth class=\"last:pe-10\"\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\u003e1746-NR8\/C\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\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e0.34 kg\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDimensions\u003c\/td\u003e\n\u003ctd\u003e144.5 x 34.6 x 130.18 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOperating Temp\u003c\/td\u003e\n\u003ctd\u003e0 to 60 deg C\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePower Consumption\u003c\/td\u003e\n\u003ctd\u003e~1.7 W\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eInput Channels\u003c\/td\u003e\n\u003ctd\u003e8 RTD\/Resistance inputs\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSupported RTD Types\u003c\/td\u003e\n\u003ctd\u003ePt100, Pt200, Pt500, Pt1000, Ni100, Ni120, Cu10\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eResolution\u003c\/td\u003e\n\u003ctd\u003e16-bit\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eConversion Method\u003c\/td\u003e\n\u003ctd\u003eSigma-Delta A\/D\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBackplane Current\u003c\/td\u003e\n\u003ctd\u003e~100 mA at 5 V DC, ~55 mA at 24 V DC\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eUpdate Rate\u003c\/td\u003e\n\u003ctd\u003e100 to 400 ms\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eIsolation\u003c\/td\u003e\n\u003ctd\u003eChannel-to-channel isolation\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003ch3\u003eI\/O Density Scaling within SLC 500 Backplane Architecture\u003c\/h3\u003e\n\u003cp\u003eThe module participates in SLC 500 backplane bus timing where input data is mapped cyclically during scan execution. Channel multiplexing is managed internally to maintain deterministic update sequencing across 8 RTD inputs, with backplane bandwidth allocation dependent on chassis slot configuration. Signal conditioning is executed prior to bus transfer to minimize scan-cycle distortion under multi-module loading conditions.\u003c\/p\u003e\n\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\n\u003cp\u003eQ: Can the module be hot-swapped under energized SLC 500 backplane conditions?\u003cbr\u003eA: Hot-swapping is not supported. Removal or insertion requires chassis power removal due to backplane electrical coupling and signal line referencing.\u003c\/p\u003e\n\u003cp\u003eQ: How does backplane current draw affect multi-slot SLC 500 configurations?\u003cbr\u003eA: Backplane consumption at 5 V DC and 24 V DC must be included in chassis power budget calculations to avoid voltage droop during full-slot population.\u003c\/p\u003e\n\u003cp\u003eQ: Does firmware level impact RTD conversion behavior or scaling?\u003cbr\u003eA: Scaling and conversion behavior is fixed in hardware conversion logic; revision suffix affects compatibility but not measurement algorithm.\u003c\/p\u003e\n\u003chr\u003e\n\u003ch3\u003eField Installation Guidelines\u003c\/h3\u003e\n\u003cul class=\"list-paddingleft-2\"\u003e\n\u003cli\u003e\n\u003cp\u003eInstall module only in SLC 500 compatible chassis slot with verified backplane alignment.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eMaintain shield continuity for RTD cable pairs and terminate shield at single-point ground reference.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eSeparate RTD wiring from high-voltage or switching conductors to reduce inductive coupling.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eVerify channel wiring configuration (2-wire, 3-wire, 4-wire) before energizing system.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eEnsure chassis power is removed prior to insertion or removal of module.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eConfirm terminal block seating and mechanical locking before system startup.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Allen-Bradley","offers":[{"title":"Default Title","offer_id":43505377968218,"sku":"1746-NR8\/C","price":123.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0612\/4601\/3530\/files\/1746-NI16IA1.jpg?v=1781605060","url":"https:\/\/www.plcmasters.com\/products\/allen-bradley-1746-nr8-c-rtd-resistance-input-module","provider":"PLC Masters Ltd.","version":"1.0","type":"link"}