{"product_id":"allen-bradley-1746-ia8-slc-500-digital-i-o-module","title":"Allen-Bradley 1746-IA8 SLC 500 Digital I\/O Module","description":"\u003ch1\u003eAllen-Bradley 1746-IA8 SLC 500 Digital I\/O Module\u003c\/h1\u003e\n\u003cp\u003eConfigured for AC signal acquisition in SLC 500 backplane scan cycles, the\u003cspan\u003e \u003c\/span\u003e\u003cstrong\u003eAllen-Bradley 1746-IA8\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003e(\u003cstrong\u003e1746-IA8\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003eAC Input Module) provides direct electrical conversion of 100\/120 V AC field states into 8-point discrete input data within the SLC 500 controller architecture.\u003c\/p\u003e\n\u003cp\u003eThe module samples 85–132 V AC input signals at 47–63 Hz and resolves each channel into backplane-updated logic states synchronized to controller scan execution. Input circuitry is designed for defined leakage discrimination and inrush handling for mechanical contact devices.\u003c\/p\u003e\n\u003ch3\u003eSuffix Breakdown \u0026amp; Model Matrix\u003c\/h3\u003e\n\u003cp\u003eNo formal suffix segmentation is defined for 1746-IA8. The model identifier represents a fixed catalog structure within the SLC 500 I\/O family without configurable ordering code extensions.\u003c\/p\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-IA8\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\u003e0.35 lbs\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePower Consumption\u003c\/td\u003e\n\u003ctd\u003e0.050 A @ 5 VDC\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eInput Channels\u003c\/td\u003e\n\u003ctd\u003e8\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eVoltage Category\u003c\/td\u003e\n\u003ctd\u003e100\/120 V AC\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOperating Voltage\u003c\/td\u003e\n\u003ctd\u003e85–132 V AC\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eInput Frequency\u003c\/td\u003e\n\u003ctd\u003e47–63 Hz\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePoints per Common\u003c\/td\u003e\n\u003ctd\u003e8\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eInput Current\u003c\/td\u003e\n\u003ctd\u003e12 mA @ 120 V AC nominal\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOFF-State Voltage\u003c\/td\u003e\n\u003ctd\u003e30 V AC max\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOFF-State Current\u003c\/td\u003e\n\u003ctd\u003e2 mA max\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eInrush Current\u003c\/td\u003e\n\u003ctd\u003e0.8 A max\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eInrush Duration\u003c\/td\u003e\n\u003ctd\u003e0.5 ms\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSignal Delay\u003c\/td\u003e\n\u003ctd\u003eON 35 ms \/ OFF 45 ms\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTerminal Type\u003c\/td\u003e\n\u003ctd\u003eRemovable terminal block\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003ch3\u003eBackplane Bus Communication and I\/O Scan Behavior\u003c\/h3\u003e\n\u003cp\u003eThe 1746-IA8 exchanges input state information through the SLC 500 chassis backplane during deterministic scan cycles. Data is mapped as fixed 8-point digital words with no field-level scaling. Backplane current draw is limited to 5 VDC logic rail consumption, remaining constant regardless of channel switching activity.\u003c\/p\u003e\n\u003ch3\u003eAC Input Conditioning and Transient Handling\u003c\/h3\u003e\n\u003cp\u003eInput stages implement impedance conditioning to stabilize 85–132 V AC field signals. Inrush current tolerance up to 0.8 A supports relay and mechanical switch closure events. OFF-state detection uses leakage current discrimination up to 2 mA to prevent false triggering under induced or residual voltage conditions.\u003c\/p\u003e\n\u003ch3\u003eFrequently Asked Questions (FAQ)\u003c\/h3\u003e\n\u003cp\u003eQ: Can the 1746-IA8 be hot-swapped in an energized SLC 500 rack?\u003cbr\u003eA: No. The module is not intended for live insertion. Backplane power should be isolated prior to installation or removal to prevent bus corruption.\u003c\/p\u003e\n\u003cp\u003eQ: Does channel switching affect backplane power consumption?\u003cbr\u003eA: No. Backplane draw remains fixed at 0.050 A @ 5 VDC independent of input state transitions.\u003c\/p\u003e\n\u003cp\u003eQ: Is firmware upgrade or configuration supported?\u003cbr\u003eA: No firmware layer exists. Input behavior is fully hardware-defined through backplane scan mapping.\u003c\/p\u003e\n\u003chr\u003e\n\u003ch3\u003eField Installation Guidelines\u003c\/h3\u003e\n\u003cp\u003eInstallation shall be performed in a compatible SLC 500 chassis slot with verified backplane alignment. The removable terminal block shall be fully seated before energizing field circuits.\u003c\/p\u003e\n\u003cp\u003eAC input wiring must be separated from low-voltage control conductors to minimize induced coupling. Shield termination should follow single-point grounding practice at the panel earth reference. Power isolation is required during module replacement to maintain backplane integrity and avoid transient data corruption.\u003c\/p\u003e","brand":"Allen-Bradley","offers":[{"title":"Default Title","offer_id":43504102735962,"sku":"1746-IA8","price":123.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0612\/4601\/3530\/files\/1746-IA82.jpg?v=1781582150","url":"https:\/\/www.plcmasters.com\/products\/allen-bradley-1746-ia8-slc-500-digital-i-o-module","provider":"PLC Masters Ltd.","version":"1.0","type":"link"}