{"product_id":"allen-bradley-1771-vhsc-very-high-speed-counter-module","title":"Allen-Bradley 1771-VHSC Very High Speed Counter Module","description":"\u003cp\u003eThe \u003cstrong\u003eAllen-Bradley 1771-VHSC\u003c\/strong\u003e, also cataloged as the \u003cstrong\u003e1771-VHSC\u003c\/strong\u003e Very High Speed Counter Module, operates as a dedicated hardware component for high-frequency pulse counting and position feedback processing within Allen-Bradley PLC-5 chassis systems.\u003c\/p\u003e\n\u003ch3\u003eHardware Specifications\u003c\/h3\u003e\n\u003cfigure class=\"table\"\u003e\n\u003ctable\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth\u003e\u003cstrong\u003eParameter\u003c\/strong\u003e\u003c\/th\u003e\n\u003cth\u003e\u003cstrong\u003eSpecification\u003c\/strong\u003e\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\u003e1771-VHSC\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\u003eOrigin\u003c\/td\u003e\n\u003ctd\u003eUSA\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e0.99 lbs (0.45 kg)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDimensions\u003c\/td\u003e\n\u003ctd\u003eStandard 1771 Single-Slot Module Form Factor\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOperating Temp\u003c\/td\u003e\n\u003ctd\u003e0 to 60 deg C (32 to 140 deg F)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePower Consumption\u003c\/td\u003e\n\u003ctd\u003e4.6 W max\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eModule Type\u003c\/td\u003e\n\u003ctd\u003eVery High Speed Counter Module\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eInput Channels\u003c\/td\u003e\n\u003ctd\u003e4 Channels\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOutput Count\u003c\/td\u003e\n\u003ctd\u003e8 Onboard Sinking\/Sourcing Outputs\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eNominal Voltage\u003c\/td\u003e\n\u003ctd\u003e24 VDC\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOperating Current\u003c\/td\u003e\n\u003ctd\u003e4 mA per input point\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBackplane Current Drive\u003c\/td\u003e\n\u003ctd\u003e1.0 A @ 5 VDC\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSignal Compatibility\u003c\/td\u003e\n\u003ctd\u003eDifferential Quadrature \/ Single-Ended Pulses\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/figure\u003e\n\u003ch3\u003eProfinet \/ EtherNet\/IP Deterministic Networks \u0026amp; Backplane Synchronization\u003c\/h3\u003e\n\u003cp\u003eThe 1771-VHSC executes real-time pulse accumulation independently of the processor scan cycle, transferring 32-bit count values across the backplane bus. High-speed input channels process quadrature signals from incremental optical encoders, supporting hardware-based compare registers that trigger eight direct 24 VDC outputs within microseconds. This architecture offloads high-frequency pulse processing from PLC-5 processors while maintaining deterministic synchronization across networked remote I\/O drops.\u003c\/p\u003e\n\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\n\u003cp\u003eQ: How does the 1771-VHSC module handle high-speed output actuation relative to the main PLC scan cycle?\u003c\/p\u003e\n\u003cp\u003eA: The 1771-VHSC features direct onboard hardware output control that triggers its 8 digital outputs instantly based on pre-programmed counter match conditions, operating independently of the PLC processor scan time.\u003c\/p\u003e\n\u003cp\u003eQ: What is the backplane current draw required by the 1771-VHSC counter module from the 1771 I\/O chassis?\u003c\/p\u003e\n\u003cp\u003eA: The module draws approximately 1.0 A at 5 VDC from the 1771 chassis backplane power supply bus.\u003c\/p\u003e\n\u003ch3\u003eField Installation Guidelines\u003c\/h3\u003e\n\u003col\u003e\n\u003cli\u003e\n\u003cstrong\u003eChassis Slot Insertion\u003c\/strong\u003e: Align the 1771-VHSC circuit board with the chassis card guides in the designated 1771 Universal I\/O slot and slide it inward until the rear edge connector firmly seats into the backplane.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eField Wiring Termination\u003c\/strong\u003e: Connect encoder quadrature channels and 24 VDC power conductors to the corresponding wiring arm terminals. Secure wiring arm latches to ensure solid electrical contact with the module header.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eShielding \u0026amp; Grounding\u003c\/strong\u003e: Route high-frequency pulse inputs using twisted-shielded cable pairs. Connect the cable drain wire directly to the panel chassis earth bus at one end to suppress high-frequency electromagnetic interference (EMI).\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWire Separation\u003c\/strong\u003e: Maintain physical separation of at least 200 mm between pulse encoder signal wiring and high-voltage AC or variable frequency drive (VFD) output cables.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThermal Airflow\u003c\/strong\u003e: Ensure panel ventilation slots above and below the 1771 I\/O chassis remain unobstructed to allow proper convection cooling across internal circuit components.\u003c\/li\u003e\n\u003c\/ol\u003e","brand":"Allen-Bradley","offers":[{"title":"Default Title","offer_id":48770302279870,"sku":"1771-VHSC","price":95.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0725\/1145\/5422\/files\/1785-L40C15_2.png?v=1787296469","url":"https:\/\/www.autooiltech.com\/products\/allen-bradley-1771-vhsc-very-high-speed-counter-module","provider":"AutoOilTech Limited","version":"1.0","type":"link"}