{"product_id":"1794-ij2-series-allen-bradley-flex-i-o-frequency-input-card","title":"1794-IJ2 Series Allen-Bradley Flex I\/O Frequency Input Card","description":"\u003ch3\u003eEngineering Architecture \u0026amp; System Matrix\u003c\/h3\u003e\n\u003cp\u003eThe \u003cstrong style=\"color: #0056b3;\"\u003e1794-IJ2\u003c\/strong\u003e module designed by \u003cstrong style=\"color: #0056b3;\"\u003eAllen-Bradley\u003c\/strong\u003e operates as a high-performance \u003cstrong style=\"color: #0056b3;\"\u003eFrequency Input Module\u003c\/strong\u003e within the distributed \u003cstrong style=\"color: #0056b3;\"\u003e1794 Flex I\/O Series\u003c\/strong\u003e. This modular DIN-rail processor card captures high-speed pulse trains, calculates dynamic rate and acceleration parameters, and provides isolated digital actuation outputs for industrial control platforms.\u003c\/p\u003e\n\u003cul style=\"list-style-type: none; padding-left: 0;\"\u003e\n  \u003cli\u003e\n\u003cstrong\u003eCatalog Number:\u003c\/strong\u003e \u003cstrong style=\"color: #0056b3;\"\u003e1794-IJ2\u003c\/strong\u003e\n\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eManufacturer \u0026amp; Brand:\u003c\/strong\u003e Rockwell Automation \/ Allen-Bradley\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eProduct Type:\u003c\/strong\u003e Flex I\/O Dual-Channel Frequency Input \u0026amp; Output Module\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eCompatible Terminal Bases:\u003c\/strong\u003e 1794-TB3G or 1794-TB3GS spring\/screw clamp bases\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eFlexBus Backplane Draw:\u003c\/strong\u003e 30 mA maximum at 5V DC\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eExternal Supply Range:\u003c\/strong\u003e 19.0 to 31.2V DC (incorporating 5% max AC ripple)\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eTechnical Specifications \u0026amp; Performance Metrics\u003c\/h3\u003e\n\u003ctable style=\"width: 100%; border-collapse: collapse; text-align: left;\"\u003e\n  \u003cthead\u003e\n    \u003ctr style=\"background-color: #f2f2f2;\"\u003e\n      \u003cth style=\"padding: 8px; border: 1px solid #ddd;\"\u003e\u003cstrong\u003ePerformance Parameter\u003c\/strong\u003e\u003c\/th\u003e\n      \u003cth style=\"padding: 8px; border: 1px solid #ddd;\"\u003e\u003cstrong\u003eEngineering Specification\u003c\/strong\u003e\u003c\/th\u003e\n    \u003c\/tr\u003e\n  \u003c\/thead\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n      \u003ctd style=\"padding: 8px; border: 1px solid #ddd;\"\u003e\u003cstrong\u003eInput Channels \u0026amp; Range\u003c\/strong\u003e\u003c\/td\u003e\n      \u003ctd style=\"padding: 8px; border: 1px solid #ddd;\"\u003e2 channels (Frequency and Gate inputs per channel); 1 to 32 kHz sine or square wave\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd style=\"padding: 8px; border: 1px solid #ddd;\"\u003e\u003cstrong\u003eMinimum Input Pulse Width\u003c\/strong\u003e\u003c\/td\u003e\n      \u003ctd style=\"padding: 8px; border: 1px solid #ddd;\"\u003e20 microseconds minimum pulse duration\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd style=\"padding: 8px; border: 1px solid #ddd;\"\u003e\u003cstrong\u003eRaw Frequency Value Format\u003c\/strong\u003e\u003c\/td\u003e\n      \u003ctd style=\"padding: 8px; border: 1px solid #ddd;\"\u003eMaximum 32,767 or 3,276.7 count scaling dependent on range selection\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd style=\"padding: 8px; border: 1px solid #ddd;\"\u003e\u003cstrong\u003eOutput Configuration\u003c\/strong\u003e\u003c\/td\u003e\n      \u003ctd style=\"padding: 8px; border: 1px solid #ddd;\"\u003e2 isolated 24V DC outputs; 1.0A max per channel continuous load\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd style=\"padding: 8px; border: 1px solid #ddd;\"\u003e\u003cstrong\u003eResolution \u0026amp; Accuracy Scope\u003c\/strong\u003e\u003c\/td\u003e\n      \u003ctd style=\"padding: 8px; border: 1px solid #ddd;\"\u003e0.01% to 0.00002% resolution across 2–1000 ms sample window; ±0.02% to ±0.00004% sampling accuracy\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd style=\"padding: 8px; border: 1px solid #ddd;\"\u003e\u003cstrong\u003eOutput Switching Speed\u003c\/strong\u003e\u003c\/td\u003e\n      \u003ctd style=\"padding: 8px; border: 1px solid #ddd;\"\u003e0.5 ms turn-on time; 1.0 ms turn-off time triggered by frequency\/acceleration alarms\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd style=\"padding: 8px; border: 1px solid #ddd;\"\u003e\u003cstrong\u003eThermal \u0026amp; Power Dissipation\u003c\/strong\u003e\u003c\/td\u003e\n      \u003ctd style=\"padding: 8px; border: 1px solid #ddd;\"\u003e4.6 Watts max at 31.2V DC; 15.6 BTU\/hr thermal output\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd style=\"padding: 8px; border: 1px solid #ddd;\"\u003e\u003cstrong\u003eEnvironmental Operating Limits\u003c\/strong\u003e\u003c\/td\u003e\n      \u003ctd style=\"padding: 8px; border: 1px solid #ddd;\"\u003e0°C to 55°C operating temperature envelope; 10A max starting current surge\u003c\/td\u003e\n    \u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch3\u003eIndustrial Applications \u0026amp; Rotary Machinery\u003c\/h3\u003e\n\u003cul style=\"list-style-type: none; padding-left: 0;\"\u003e\n  \u003cli\u003e\n\u003cstrong\u003eHigh-Speed Turbine Overspeed Protection:\u003c\/strong\u003e Monitors emergency shaft rotational velocity to trigger high-speed trip solenoids.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003ePositive Displacement Flow Metering:\u003c\/strong\u003e Integrates pulse outputs from turbine flowmeters to calculate precise volumetric flow rates.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eConveyor Speed \u0026amp; Acceleration Tracking:\u003c\/strong\u003e Measures rotational velocity shifts on heavy industrial drive assemblies and stamping presses.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eDiagnostic Capabilities \u0026amp; Fault Indication\u003c\/h3\u003e\n\u003cul style=\"list-style-type: none; padding-left: 0;\"\u003e\n  \u003cli\u003e\n\u003cstrong\u003eWire-Off Fault Detection:\u003c\/strong\u003e Dedicated front-panel status LED highlights open-circuit wiring faults immediately.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eFront-Panel I\/O Monitoring:\u003c\/strong\u003e Individual channel input, output, and power status indicators provide instant visual loop verification.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eAlarm Switching Logic:\u003c\/strong\u003e Assigns output switching thresholds directly to frequency thresholds or rate-of-change acceleration alarms.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eGlobal PLC Spare HUB's Insight\u003c\/h3\u003e\n\u003cp\u003eDeploying high-speed pulse and frequency counting in distributed I\/O drops demands rigorous attention to grounding and signal shielding. The \u003cstrong style=\"color: #0056b3;\"\u003e1794-IJ2\u003c\/strong\u003e processes signals up to 32 kHz, making it exceptionally sensitive to electromagnetic interference if sensor cables run parallel to high-voltage motor lines. When configuring sample windows between 2 ms and 1000 ms, engineers must balance resolution requirements against control loop update times. Additionally, ensure the terminal base (1794-TB3G or 1794-TB3GS) is securely seated on the DIN rail with the FlexBus connector fully engaged to prevent intermittent backplane communication errors during high-vibration plant operations.\u003c\/p\u003e\n\n\u003ch3\u003eLogistics, Packaging \u0026amp; Warranty Terms\u003c\/h3\u003e\n\u003cul style=\"list-style-type: none; padding-left: 0;\"\u003e\n  \u003cli\u003e\n\u003cstrong\u003eCondition Status:\u003c\/strong\u003e 100% New \u0026amp; Original factory-sealed hardware.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eWarranty Coverage:\u003c\/strong\u003e Comprehensive 12 Months factory warranty from date of purchase.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eOrder Handling:\u003c\/strong\u003e Rapid 24 to 48 hour processing and dispatch window.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eGlobal Express Shipping:\u003c\/strong\u003e Fast, secure air delivery worldwide via FedEx, UPS, and DHL.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\n\n\u003ch3\u003eHow do the gate input channels function alongside frequency inputs on the 1794-IJ2?\u003c\/h3\u003e\n\u003cp\u003eEach channel features both a frequency input and a gate input, allowing external control signals to start, stop, or window pulse counting intervals for precise batch or rotational measurements.\u003c\/p\u003e\n\n\u003ch3\u003eWhat surge current capacity do the isolated DC outputs support during actuation?\u003c\/h3\u003e\n\u003cp\u003eThe 24V DC outputs support a surge current of up to 2 Amps for 50 milliseconds, which is repeatable every 2 seconds to handle inductive solenoid loads.\u003c\/p\u003e\n\n\u003ch3\u003eWhy is sample frequency configuration critical for module resolution?\u003c\/h3\u003e\n\u003cp\u003eModule resolution scales dynamically from 0.01% down to 0.00002% depending on the configured sample frequency window ranging from 2 ms to 1000 ms.\u003c\/p\u003e\n\n\u003ch3\u003eWhat selection criteria apply when choosing between 1794-TB3G and 1794-TB3GS terminal bases?\u003c\/h3\u003e\n\u003cp\u003eSelect the 1794-TB3G for standard screw clamp field wiring or the 1794-TB3GS when spring-clamp terminal connections are preferred for high-vibration cabinet installations.\u003c\/p\u003e\n\n\u003ch3\u003eHow does the module respond when an input signal exceeds the maximum frequency range?\u003c\/h3\u003e\n\u003cp\u003eInput frequencies exceeding the 32 kHz threshold or reaching maximum range limits will clip raw register counts at 32,767 or 3,276.7 depending on the selected engineering scale.\u003c\/p\u003e","brand":"Allen-Bradley","offers":[{"title":"Default Title","offer_id":45013908291766,"sku":"1794-IJ2","price":112.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0722\/7863\/8774\/files\/1794-IJ2.jpg?v=1793168536","url":"https:\/\/www.plcsparehub.com\/products\/1794-ij2-series-allen-bradley-flex-i-o-frequency-input-card","provider":"Global PLC Spare Hub","version":"1.0","type":"link"}