{"product_id":"allen-bradley-1746-ig16-slc-500-digital-dc-ttl-input-module","title":"Allen-Bradley 1746-IG16 SLC 500 Digital DC TTL Input Module","description":"\u003ch1\u003eAllen-Bradley 1746-IG16 SLC 500 Digital DC TTL Input Module\u003c\/h1\u003e\n\u003cp\u003eThe\u003cspan\u003e \u003c\/span\u003e\u003cstrong\u003eAllen-Bradley 1746-IG16\u003c\/strong\u003e, also cataloged as the\u003cspan\u003e \u003c\/span\u003e\u003cstrong\u003e1746-IG16\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003eDigital DC Input Module, serves as the primary TTL level input module utilized to execute 4.5–5.5 VDC signal acquisition across SLC 500 PLC platforms.\u003c\/p\u003e\n\u003cp\u003eConfigured for direct TTL and BCD signal interfacing in SLC 500 backplane scan cycles, the module converts 16-channel 5 VDC source-level inputs into discrete logic states for controller processing. Signal conditioning is optimized for low-voltage digital sources with tight switching thresholds and deterministic scan synchronization.\u003c\/p\u003e\n\u003ch3\u003eSuffix Breakdown \u0026amp; Model Matrix\u003c\/h3\u003e\n\u003cp\u003eNo structured suffix or option code segmentation is defined for 1746-IG16. The model number represents a fixed SLC 500 catalog identifier without configurable hardware variants.\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-IG16\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\u003e0.50 lbs\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePower Consumption\u003c\/td\u003e\n\u003ctd\u003e140 mA @ 5 VDC backplane (1.0 W approx)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eInput Channels\u003c\/td\u003e\n\u003ctd\u003e16\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eVoltage Range\u003c\/td\u003e\n\u003ctd\u003e4.5–5.5 VDC\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eInput Type\u003c\/td\u003e\n\u003ctd\u003eTTL \/ BCD Source\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBackplane Current\u003c\/td\u003e\n\u003ctd\u003e140 mA @ 5 VDC\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSignal Delay\u003c\/td\u003e\n\u003ctd\u003e0.25 ms \/ 0.5 ms\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eStep Response\u003c\/td\u003e\n\u003ctd\u003e100 ms ON \/ 2.5 ms OFF\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWatt Per Point\u003c\/td\u003e\n\u003ctd\u003e0.02 W\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eI\/O Connection\u003c\/td\u003e\n\u003ctd\u003e1746-HT \/ 1746-HCA\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTerminal Block\u003c\/td\u003e\n\u003ctd\u003e1746-RT25B\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSlot Requirement\u003c\/td\u003e\n\u003ctd\u003eSingle slot\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003ch3\u003eBackplane Bus Communication and I\/O Density Scaling\u003c\/h3\u003e\n\u003cp\u003eThe module exchanges 16-point TTL input data through the SLC 500 backplane during cyclic scan execution. Backplane load is fixed at 140 mA @ 5 VDC, independent of input switching activity. I\/O density scaling is fixed per module with no field expansion capability. Signal propagation follows deterministic scan timing governed by controller cycle execution.\u003c\/p\u003e\n\u003ch3\u003eTTL Input Threshold Behavior and Signal Conditioning\u003c\/h3\u003e\n\u003cp\u003eInput channels operate within 4.5–5.5 VDC logic levels. Internal threshold comparators stabilize signal transitions for TTL and BCD sources. Low signal delay (0.25–0.5 ms) supports high-speed digital state capture. OFF-state interpretation is defined by internal pull-down reference within module logic circuitry.\u003c\/p\u003e\n\u003ch3\u003eFrequently Asked Questions (FAQ)\u003c\/h3\u003e\n\u003cp\u003eQ: Does the 1746-IG16 support hot-swapping in an energized SLC 500 chassis?\u003cbr\u003eA: No. Module insertion or removal must be performed with backplane power removed to prevent bus instability and logic corruption.\u003c\/p\u003e\n\u003cp\u003eQ: What is the impact of full 16-channel activation on backplane load?\u003cbr\u003eA: Backplane consumption remains fixed at 140 mA @ 5 VDC regardless of channel switching state.\u003c\/p\u003e\n\u003cp\u003eQ: Can the module interface directly with 24 VDC field signals?\u003cbr\u003eA: No. Input range is strictly limited to 4.5–5.5 VDC TTL levels; higher voltages require external signal conditioning.\u003c\/p\u003e\n\u003chr\u003e\n\u003ch3\u003eField Installation Guidelines\u003c\/h3\u003e\n\u003cp\u003eThe module shall be installed in a single-slot SLC 500 chassis position with correct backplane alignment. The 1746-RT25B terminal block must be fully seated before energizing field circuits.\u003c\/p\u003e\n\u003cp\u003eWiring shall follow TTL signal integrity practices with short conductor runs and minimal loop area. Shielding should be grounded at a single panel reference point to reduce high-frequency coupling. Separation from AC and high-voltage DC wiring is required to prevent induced noise on low-level TTL inputs.\u003c\/p\u003e","brand":"Allen-Bradley","offers":[{"title":"Default Title","offer_id":43504685252698,"sku":"1746-IG16","price":123.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0612\/4601\/3530\/files\/1746-IG162.jpg?v=1781591809","url":"https:\/\/www.plcmasters.com\/products\/allen-bradley-1746-ig16-slc-500-digital-dc-ttl-input-module","provider":"PLC Masters Ltd.","version":"1.0","type":"link"}