{"product_id":"allen-bradley-1791d-8b8p-compactblock-i-o-combination-base-block","title":"Allen-Bradley 1791D-8B8P CompactBlock I\/O Combination Base Block","description":"\u003cp\u003eThe Allen-Bradley \u003cstrong\u003e1791D-8B8P\u003c\/strong\u003e is a DeviceNet-compatible CompactBlock I\/O combination base module designed for distributed industrial automation architectures. This unit integrates internal I\/O circuits, a built-in power supply, and a DeviceNet adapter into a single housing, streamlining panel space and reducing external wiring requirements for discrete control tasks.\u003c\/p\u003e\n\u003ch3\u003eNetwork Communication and Architecture\u003c\/h3\u003e\n\u003cp\u003eOperating as a slave device on a DeviceNet network, this module supports polled, cyclic, and change-of-state data transfer modes. It features automatic baud rate detection to seamlessly match network communication speeds configured by the master scanner.\u003c\/p\u003e\n\u003ch3\u003eDiscrete Input and Output Channels\u003c\/h3\u003e\n\u003cp\u003eThe module provides 8 sinking discrete inputs and 8 sourcing discrete outputs to interface with various field sensors and actuators. Input filtering helps minimize false triggers caused by electrical noise or contact bounce, while output channels include built-in short-circuit protection.\u003c\/p\u003e\n\u003ch3\u003ePower Requirements and Mounting\u003c\/h3\u003e\n\u003cp\u003eCommunication power is supplied directly via the DeviceNet network, whereas inputs and outputs require an independent 24 VDC external power source. The compact base block mounts securely onto standard DIN rails or directly onto flat industrial control panels.\u003c\/p\u003e\n\u003ch3\u003eTechnical Parameters\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\u003eBrand\u003c\/td\u003e\n\u003ctd\u003eAllen-Bradley\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eModel\u003c\/td\u003e\n\u003ctd\u003e1791D-8B8P\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eProduct Line\u003c\/td\u003e\n\u003ctd\u003eCompactBlock I\/O\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eNetwork Protocol\u003c\/td\u003e\n\u003ctd\u003eDeviceNet\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eInputs per Block\u003c\/td\u003e\n\u003ctd\u003e8 (Sinking)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOutputs per Block\u003c\/td\u003e\n\u003ctd\u003e8 (Sourcing)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOutput Current\u003c\/td\u003e\n\u003ctd\u003e0.5 A maximum per output\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eExternal Power Supply\u003c\/td\u003e\n\u003ctd\u003e24 VDC\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eEnclosure Rating\u003c\/td\u003e\n\u003ctd\u003eIEC IP20\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e0.35 lbs (0.16 kg)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/figure\u003e\n\u003cp\u003eFrequently Asked Questions\u003c\/p\u003e\n\u003cp\u003eQ: What type of external power supply is required for the input and output channels?A: The inputs and outputs require an independent 24 VDC external power source separate from the DeviceNet network power.\u003c\/p\u003e\n\u003cp\u003eQ: How does the module communicate with the master controller?A: It operates as a slave device on a DeviceNet network, supporting polled, cyclic, and change-of-state data exchanges configured via the scanner module.\u003c\/p\u003e\n\u003cp\u003eQ: What action does the module take if the DeviceNet network connection fails?A: If the network connection drops or the scanner enters a fault state, the module transitions to a fault state and resets its outputs by default.\u003c\/p\u003e","brand":"Allen-Bradley","offers":[{"title":"Default Title","offer_id":53056656310552,"sku":"1791D-8B8P","price":270.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0892\/3483\/3688\/files\/1791D-OB16P_Cocoai.jpg?v=1790734271","url":"https:\/\/www.innoplcsync.com\/products\/allen-bradley-1791d-8b8p-compactblock-i-o-combination-base-block","provider":"InnoPLC Sync Co., Ltd.","version":"1.0","type":"link"}