{"product_id":"allen-bradley-1794-asb2-flex-io-remote-i-o-adapter","title":"Allen-Bradley 1794-ASB2 FLEX IO Remote I\/O Adapter","description":"\u003ch2\u003eProduct Overview\u003c\/h2\u003e\n\u003cp\u003eThe \u003cstrong style=\"color: #0056b3;\"\u003e1794-ASB2\u003c\/strong\u003e is a compact, high-performance Remote I\/O (RIO) Network Adapter from Allen-Bradley's FLEX IO product line. Functioning as an intelligent network interface node, this module links up to 2 distributed local I\/O modules directly to a master PLC controller over an Allen-Bradley Remote I\/O network link. This 2-slot space-saving adapter is engineered to transmit discrete and analog telemetry data over long physical distances, reducing heavy field wiring runs back to the main control panel.\u003c\/p\u003e\n\n\u003ch2\u003eCore Features\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003e2-Module Network Capacity:\u003c\/strong\u003e Manages real-time addressing, scanning, and data mapping for up to two attached FLEX IO modules.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003e500V AC Galvanic Isolation:\u003c\/strong\u003e Features high-voltage optical isolation to prevent field voltage spikes from damaging the internal backplane logic.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eWide Operating Temperature:\u003c\/strong\u003e Rugged design operates reliably from −20°C up to +60°C, making it ideal for remote field enclosures.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eFlexible DC Power Options:\u003c\/strong\u003e Operates across a wide input voltage range of 11V to 31.2V DC to tolerate unstable field power links.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eTechnical Specifications\u003c\/h2\u003e\n\u003ctable style=\"width: 100%; border-collapse: collapse;\"\u003e\n  \u003cthead\u003e\n    \u003ctr style=\"background-color: #f2f2f2;\"\u003e\n      \u003cth style=\"border: 1px solid #dddddd; text-align: left; padding: 6px;\"\u003eParameter\u003c\/th\u003e\n      \u003cth style=\"border: 1px solid #dddddd; text-align: left; padding: 6px;\"\u003eData\u003c\/th\u003e\n    \u003c\/tr\u003e\n  \u003c\/thead\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n      \u003ctd style=\"border: 1px solid #dddddd; padding: 6px;\"\u003e\u003cstrong\u003eModel Number\u003c\/strong\u003e\u003c\/td\u003e\n      \u003ctd style=\"border: 1px solid #dddddd; padding: 6px;\"\u003e1794-ASB2 (FLEX IO Series)\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd style=\"border: 1px solid #dddddd; padding: 6px;\"\u003e\u003cstrong\u003eModule Function\u003c\/strong\u003e\u003c\/td\u003e\n      \u003ctd style=\"border: 1px solid #dddddd; padding: 6px;\"\u003eRemote I\/O (RIO) Network Communication Adapter\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd style=\"border: 1px solid #dddddd; padding: 6px;\"\u003e\u003cstrong\u003eI\/O Module Capacity\u003c\/strong\u003e\u003c\/td\u003e\n      \u003ctd style=\"border: 1px solid #dddddd; padding: 6px;\"\u003eSupports up to 2 expansion modules max\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd style=\"border: 1px solid #dddddd; padding: 6px;\"\u003e\u003cstrong\u003eNominal Supply Voltage\u003c\/strong\u003e\u003c\/td\u003e\n      \u003ctd style=\"border: 1px solid #dddddd; padding: 6px;\"\u003e24V DC\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd style=\"border: 1px solid #dddddd; padding: 6px;\"\u003e\u003cstrong\u003eInput Voltage Boundaries\u003c\/strong\u003e\u003c\/td\u003e\n      \u003ctd style=\"border: 1px solid #dddddd; padding: 6px;\"\u003e11V to 31.2V DC operational window\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd style=\"border: 1px solid #dddddd; padding: 6px;\"\u003e\u003cstrong\u003eInternal Backplane Current\u003c\/strong\u003e\u003c\/td\u003e\n      \u003ctd style=\"border: 1px solid #dddddd; padding: 6px;\"\u003e0.5 Amps max allocation @ 24V DC supply\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd style=\"border: 1px solid #dddddd; padding: 6px;\"\u003e\u003cstrong\u003eSurge Isolation Threshold\u003c\/strong\u003e\u003c\/td\u003e\n      \u003ctd style=\"border: 1px solid #dddddd; padding: 6px;\"\u003e500V AC continuous barrier protection\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd style=\"border: 1px solid #dddddd; padding: 6px;\"\u003e\u003cstrong\u003eModule Hardware Weight\u003c\/strong\u003e\u003c\/td\u003e\n      \u003ctd style=\"border: 1px solid #dddddd; padding: 6px;\"\u003e0.2 kg (0.44 lbs) compact footprint\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd style=\"border: 1px solid #dddddd; padding: 6px;\"\u003e\u003cstrong\u003eEnvironmental Temperature Limits\u003c\/strong\u003e\u003c\/td\u003e\n      \u003ctd style=\"border: 1px solid #dddddd; padding: 6px;\"\u003e−20°C to 60°C (−4°F to 140°F) active operating range\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd style=\"border: 1px solid #dddddd; padding: 6px;\"\u003e\u003cstrong\u003eHarmonized Tariff Code\u003c\/strong\u003e\u003c\/td\u003e\n      \u003ctd style=\"border: 1px solid #dddddd; padding: 6px;\"\u003e8537101190\u003c\/td\u003e\n    \u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch2\u003eEngineering \u0026amp; Installation Guide\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eNetwork Node Address Configuration:\u003c\/strong\u003e Set the physical hardware DIP switches located on the side of the 1794-ASB2 module to establish its unique remote I\/O station address before snapping the unit onto the DIN rail.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eFLEX IO Interlocking Alignment:\u003c\/strong\u003e Slide the network adapter firmly onto the leftmost slot of the terminal base rack assembly. Secure the module using the built-in mechanical latches to protect the backplane pins from industrial vibration.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003ePower Supply Routing Rules:\u003c\/strong\u003e Wire external 24V DC power within the safe 11–31.2V DC window directly to the designated power terminals. To ensure stable startup cycles, ensure your power supply has enough headroom to handle the adapter's 0.5A backplane draw.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eRemote I\/O Trunk Line Termination:\u003c\/strong\u003e When wiring the RIO network trunk, always place an approved terminating resistor across the blue and clear data lines at both physical ends of the network link to match line impedance and prevent data echo.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eTechnical FAQs\u003c\/h2\u003e\n\u003cp\u003e\u003cstrong\u003eQ1: How does the 1794-ASB2 handle multi-rack addressing since it only holds two modules?\u003c\/strong\u003e\u003cbr\u003e\nA1: The 1794-ASB2 is engineered specifically for low-density distributed control points. It maps data into fractional or partial rack segments within the master PLC’s I\/O image table, allowing engineers to efficiently place small 2-slot nodes where a large 8-slot adapter would waste cabinet space.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eQ2: What is the main structural advantage of the 500V AC isolation specification?\u003c\/strong\u003e\u003cbr\u003e\nA2: In vast industrial plants, long cable runs can experience sudden voltage surges from lightning, heavy motor switching, or ground potential shifts. The 500V AC electrical barrier safely uncouples the communication lines from the field loop circuitry, confining any field faults to the local terminal strip.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eQ3: Can I hot-swap the 1794-ASB2 network adapter module itself while the system is running?\u003c\/strong\u003e\u003cbr\u003e\nA3: No. While individual I\/O modules attached to the underlying terminal bases can support Removal and Insertion Under Power (RIUP), pulling the primary 1794-ASB2 adapter module will immediately break the backplane power and communication loops, dropping the entire node offline from the master PLC scanner.\u003c\/p\u003e","brand":"Allen-Bradley","offers":[{"title":"Default Title","offer_id":51050311286916,"sku":"1794-ASB2","price":112.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0958\/7454\/7844\/files\/1794-ASB2.jpg?v=1780669871","url":"https:\/\/www.etowonauto.com\/products\/allen-bradley-1794-asb2-flex-io-remote-i-o-adapter","provider":"Etowon Auto","version":"1.0","type":"link"}