{"product_id":"allen-bradley-1771-dcm-direct-communication-module","title":"Allen-Bradley 1771-DCM Direct Communication Module","description":"\u003ch2\u003eAllen-Bradley 1771-DCM Direct Communication Module\u003c\/h2\u003e\n\u003cp\u003eThe \u003cstrong\u003eAllen-Bradley 1771-DCM\u003c\/strong\u003e, also cataloged as the \u003cstrong\u003e1771-DCM\u003c\/strong\u003e Direct Communication Module, operates as a dedicated hardware component for Remote I\/O serial communication and data transfer within PLC-5 control system platforms. The module provides direct processor-to-processor communication through RIO protocol with discrete and block transfer functions.\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\u003eParameter\u003c\/th\u003e\n\u003cth\u003eSpecification\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-DCM\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\u003eUnited States\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e1.75 lbs\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDimensions\u003c\/td\u003e\n\u003ctd\u003e25.4 cm x 2.5 cm x 15.2 cm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOperating Temp\u003c\/td\u003e\n\u003ctd\u003e32 to 131 deg F (0 to 55 deg C)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePower Consumption\u003c\/td\u003e\n\u003ctd\u003e1.2 A at 5 VDC from PLC-5 chassis backplane\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eModule Type\u003c\/td\u003e\n\u003ctd\u003eDirect Communication Module (DCM)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eProduct Line\u003c\/td\u003e\n\u003ctd\u003ePLC-5\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCommunication Protocol\u003c\/td\u003e\n\u003ctd\u003eRemote I\/O (RIO)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTransmission Rate\u003c\/td\u003e\n\u003ctd\u003e57.6 Kbaud at 10,000 ft cable length; 115.2 Kbaud at 5,000 ft cable length\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTransfer Modes\u003c\/td\u003e\n\u003ctd\u003eDiscrete Data Transfer and Block Transfer\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDiscrete Data Capacity\u003c\/td\u003e\n\u003ctd\u003eUp to 7 words plus 1 status word\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBlock Transfer Capacity\u003c\/td\u003e\n\u003ctd\u003eUp to 63 words plus 1 status word\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eResponse Time\u003c\/td\u003e\n\u003ctd\u003e15 ms\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCommunication Cable\u003c\/td\u003e\n\u003ctd\u003eBelden 9463 or equivalent\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eHumidity Range\u003c\/td\u003e\n\u003ctd\u003e5-95 % relative humidity\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/figure\u003e\n\u003ch3\u003eEtherNet\/IP and PLC Backplane Communication Characteristics\u003c\/h3\u003e\n\u003cp\u003eThe 1771-DCM provides direct serial communication between supervisory processors and local PLC processors through the Remote I\/O network interface. The module supports deterministic PLC-5 data exchange using RIO communication architecture and block-transfer operations.\u003c\/p\u003e\n\u003cp\u003eThe communication design supports industrial control network integration through defined transmission rates and cable distance configurations. Backplane bus communication provides data exchange between the module and PLC-5 processor using block-transfer instructions. The module supports I\/O density scaling by transferring discrete data and larger block data structures through the RIO channel.\u003c\/p\u003e\n\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\n\u003cp\u003eQ: What type of communication protocol is supported by the 1771-DCM?\u003cbr\u003eA: The module supports Allen-Bradley Remote I\/O (RIO) protocol through its serial communication interface.\u003c\/p\u003e\n\u003cp\u003eQ: What backplane power requirement applies to the 1771-DCM?\u003cbr\u003eA: The module requires 1.2 A at 5 VDC from the PLC-5 chassis backplane.\u003c\/p\u003e\n\u003cp\u003eQ: What transfer modes are available with the 1771-DCM?\u003cbr\u003eA: The module supports discrete data transfer and block transfer operations. Discrete transfer supports up to 7 words plus 1 status word, while block transfer supports up to 63 words plus 1 status word.\u003c\/p\u003e\n\u003ch3\u003eField Installation Guidelines\u003c\/h3\u003e\n\u003cp\u003eInstall the 1771-DCM module into a compatible PLC-5 1771 I\/O chassis slot using the correct keying configuration. Verify chassis power capacity before installation and disconnect power during module insertion or removal.\u003c\/p\u003e\n\u003cp\u003eUse the specified communication cable type or an equivalent cable suitable for Remote I\/O applications. Route communication wiring separately from high-voltage and high-current conductors to reduce electromagnetic interference. Maintain proper cable shielding and grounding practices according to industrial installation standards.\u003c\/p\u003e\n\u003cp\u003eConfirm RIO node configuration, cable routing, and PLC-5 block-transfer parameters before placing the module into operation.\u003c\/p\u003e","brand":"Allen-Bradley","offers":[{"title":"Default Title","offer_id":43668243939418,"sku":"1771-DCM","price":123.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0612\/4601\/3530\/files\/1771-DCM2.jpg?v=1784269780","url":"https:\/\/www.plcmasters.com\/products\/allen-bradley-1771-dcm-direct-communication-module","provider":"PLC Masters Ltd.","version":"1.0","type":"link"}