{"product_id":"allen-bradley-1771-ob-plc-5-digital-dc-output-module","title":"Allen-Bradley 1771-OB PLC-5 Digital DC Output Module","description":"\u003cp\u003eThe \u003cstrong\u003e1771-OB\u003c\/strong\u003e is an 8-channel digital solid-state electronic device engineered for the \u003cstrong\u003ePLC-5 \/ 1771 I\/O Platform\u003c\/strong\u003e to drive low-voltage direct current industrial control hardware. It provides electrical switching paths for various field components, including DC motor drivers, status indicators, and industrial solenoid valves. The internal control micro-logic is energized via the local \u003cstrong\u003eI\/O chassis\u003c\/strong\u003e backplane rail, drawing a maximum current of 165 mA to maintain structural optoelectronic isolation between high-level plant field elements and core processor busses. System integration is established through the standard \u003cstrong\u003e1771-WA\u003c\/strong\u003e wiring arm connector assembly, permitting physical hot-swapping or card replacement sequences without disturbing landed field terminal connections.\u003c\/p\u003e\n\u003ch3\u003eFeatures\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eHigh-Density Output Distribution\u003c\/strong\u003e: Integrates eight independent solid-state DC switching circuits within a single-slot chassis package.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDedicated Short-Circuit Protection\u003c\/strong\u003e: Individual 2 A, 8AG protective fuses mounted per channel safeguard the module against severe field overcurrent hazards.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eVisual Status Array\u003c\/strong\u003e: Equipped with nine front-panel diagnostic LEDs providing localized visualization of blown-fuse status and specific channel conduction states.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDirect Input Interlocking\u003c\/strong\u003e: Supports zero-potential ground reference looping to directly drive discrete DC input modules, such as the 1771-IB receiver block.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOptoelectronic Backplane Protection\u003c\/strong\u003e: Incorporates continuous 1500 Vca (rms) galvanic isolation to prevent destructive external voltage transients from damaging backplane control logic.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMechanical Slot Keying\u003c\/strong\u003e: Backplane socket keying fields restrict module slot alignment, ensuring only matched electrical module types sit within defined wiring nests.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eApplications\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eDistributed control of factory floor solenoid-actuated pneumatic manifolds.\u003c\/li\u003e\n\u003cli\u003eDirect activation of low-current DC motor speed control enable drives.\u003c\/li\u003e\n\u003cli\u003eRemote instrumentation control panels and pilot lamp illumination matrix lines.\u003c\/li\u003e\n\u003cli\u003eInter-rack logic interlocking with low-voltage input hardware sub-assemblies.\u003c\/li\u003e\n\u003c\/ul\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\u003e\u003cstrong\u003eManufacturer\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eAllen-Bradley \/ Rockwell Automation\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eModel\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e1771-OB\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eProduct Series\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003ePLC-5 \/ 1771 I\/O\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eModule Type\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eDigital DC Output Driver Module\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eOutputs Per Module\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e8\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eChassis Compatibility\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e1771 I\/O Chassis\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eInput Operational Voltage Range\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e10 Vdc to 27 Vdc\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eOutput Current Capacity\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e1.5 A per individual output (not to exceed 8 A total per module)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eMaximum Current Surge\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e4 A for 1 ms, repeatable at 1 s intervals\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eOff-State Leakage Current\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e1 mA maximum per output\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eOn-State Voltage Drop\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e2 Vdc maximum\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eSignal Transmission Delay\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e10 ms (On to Off and Off to On states)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003ePower Dissipation\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e0.9 Watts minimum, 16.9 Watts maximum\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eThermal Dissipation\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e3.0 BTU\/h minimum, 57.6 BTU\/h maximum\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eBackplane Logic Current Demand\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e165 mA @ 5 Vdc plus\/minus 5%\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eOptoelectric Isolation\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e1500 Vca (rms)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eOperating Temperature Range\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e0 degC to 60 degC\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eStorage Temperature Range\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e-40 degC to 85 degC\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eRelative Ambient Humidity\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e5% to 95% (non-condensing)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eField Wiring Specifications\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eFlexible cable with 1.5 mm2 nominal cross-section\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eBackplane Plastic Keying Slots\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eBetween positions 4 and 6, and between positions 18 and 20\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eInternal Fusing\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e2 A, 8AG rating (one individual fuse per output path)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eTerminal Connection Block\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e1771-WA Wiring Arm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/figure\u003e\n\u003ch3\u003eConnections\/Interfaces\u003c\/h3\u003e\n\u003cfigure class=\"table\"\u003e\n\u003ctable\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth\u003e\u003cstrong\u003eConnector Terminal Pin\u003c\/strong\u003e\u003c\/th\u003e\n\u003cth\u003e\u003cstrong\u003eFunction\u003c\/strong\u003e\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eTerminal A\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e+DC Voltage Supply Input Reference\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eTerminal 0\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eDigital Output Channel 0 Signal Line\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eTerminal 1\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eDigital Output Channel 1 Signal Line\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eTerminal 2\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eDigital Output Channel 2 Signal Line\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eTerminal 3\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eDigital Output Channel 3 Signal Line\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eTerminal 4\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eDigital Output Channel 4 Signal Line\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eTerminal 5\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eDigital Output Channel 5 Signal Line\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eTerminal 6\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eDigital Output Channel 6 Signal Line\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eTerminal 7\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eDigital Output Channel 7 Signal Line\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eTerminal B\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eDC Common Ground Return Reference\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/figure\u003e\n\u003ch3\u003eEngineering Notes\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eTerminal to Bit Discrepancy\u003c\/strong\u003e: The terminal channel designations etched on the physical 1771-WA wiring arm hardware do not directly map to software internal image register data bits. Refer strictly to the system allocation table when building control code.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePotential Equalization\u003c\/strong\u003e: When cross-linking an output channel directly into an input processing unit (such as a 1771-IB), a common power supply loop must feed both blocks to tie all reference grounds to an identical voltage potential.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePolarity Critical Warning\u003c\/strong\u003e: Correct structural polarity must be maintained on all direct current power terminals. Applying alternating current (AC) power configurations or cross-wiring polarity rails will result in critical module hardware destruction.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBackplane Power Balancing\u003c\/strong\u003e: The 165 mA backplane current consumption must be calculated into the aggregate power supply capacity budget of the specific 1771 chassis rack to avoid thermal overloading or backplane dip errors.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eField Guidelines\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eElectrostatic Grounding Procedures\u003c\/strong\u003e: Operators must latch an approved ESD wrist grounding strap to a structural physical ground point or discharge local potentials by touching an earth-grounded steel frame before touching card edges.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePlastic Keying Installation\u003c\/strong\u003e: Ensure the chassis backplane keying pegs are properly seated at the factory positions (between pins 4\/6 and pins 18\/20) to prevent the accidental insertion of mismatched voltage cards.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eChassis De-energization\u003c\/strong\u003e: Complete chassis rack power downcycles are required prior to sliding the driver module out of its physical slot to protect operators and prevent inductive backplane transients.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFuse Extraction Protocol\u003c\/strong\u003e: To safely swap a compromised fuse assembly, release the front mechanical swing arm latch, withdraw the board housing, undo the two case retention screws, and replace the spent 2 A, 8AG component inside.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eTechnical \u0026amp; Procurement FAQ\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003eQ: What specific fuse replacement specification must be used if a channel drops out?\u003c\/strong\u003e A: Each individual output switch is paired with a standard 2 A, 8AG form-factor fuse accessible underneath the card side cover.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eQ: Can this DC driver module be safely slotted into the leftmost slot of a 1771 chassis?\u003c\/strong\u003e A: No, the far-left slot of the 1771 chassis configuration is structurally reserved for the master processor module or remote I\/O network adapter head.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eQ: Does the module display indicators on the front face for individual circuit diagnostics?\u003c\/strong\u003e A: Yes, it features one dedicated red LED for blown fuse notification alongside eight individual red status LEDs that light up when an output channel is actively energized.\u003c\/p\u003e","brand":"Allen-Bradley","offers":[{"title":"Default Title","offer_id":52695182606699,"sku":"1771-OB","price":100.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0953\/3227\/0443\/files\/allen-bradley-1771-ob-digital-dc-output-driver-module-3votzyt5u4d_51486138-8d7c-4a78-b921-cc00c9f77c03.jpg?v=1766114346","url":"https:\/\/www.plcprotech.com\/products\/allen-bradley-1771-ob-plc-5-digital-dc-output-module","provider":"PLC ProTech Ltd.","version":"1.0","type":"link"}