{"product_id":"allen-bradley-1756-cjc-a-controllogix-cold-junction-compensation-module","title":"Allen-Bradley 1756-CJC\/A ControlLogix Cold Junction Compensation Module","description":"\u003ch1 class=\"PDq2pG_selectionAnchorContainer\"\u003eAllen-Bradley 1756-CJC\/A ControlLogix Cold Junction Compensation Module\u003cspan class=\"PDq2pG_selectionAnchor\"\u003e\u003c\/span\u003e\n\u003c\/h1\u003e\n\u003cp\u003eConfigured for thermocouple reference junction temperature correction in ControlLogix analog input signal conditioning chains, the\u003cspan\u003e \u003c\/span\u003e\u003cstrong\u003eAllen-Bradley 1756-CJC\/A\u003c\/strong\u003e, also cataloged as the\u003cspan\u003e \u003c\/span\u003e\u003cstrong\u003e1756-CJC\/A\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003ecold junction compensation module, provides direct physical temperature reference compensation for thermocouple measurement circuits within ControlLogix I\/O architectures. The device interfaces mechanically with the RTB assembly of compatible analog input modules and supplies junction temperature correction data used during thermoelectric voltage linearization.\u003c\/p\u003e\n\u003ch3\u003eHardware Specifications\u003c\/h3\u003e\n\u003ctable class=\"w-fit min-w-(--thread-content-width)\"\u003e\n\u003cthead\u003e\n\u003ctr class=\"firstRow\"\u003e\n\u003cth class=\"last:pe-10\"\u003eParameter\u003c\/th\u003e\n\u003cth class=\"last:pe-10\"\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\u003e1756-CJC\/A\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\u003eOperating Temp\u003c\/td\u003e\n\u003ctd\u003eMatches host module specification\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePower Consumption\u003c\/td\u003e\n\u003ctd\u003ePassive (backplane dependent)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFunction\u003c\/td\u003e\n\u003ctd\u003eCold junction compensation for thermocouple inputs\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCompatibility\u003c\/td\u003e\n\u003ctd\u003e1756-IT6I, 1756-IT6, 1756-IT16\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eInstallation Interface\u003c\/td\u003e\n\u003ctd\u003eRTB (Removable Terminal Block)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eEnclosure Type\u003c\/td\u003e\n\u003ctd\u003eOpen-style, panel-mounted\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCertifications\u003c\/td\u003e\n\u003ctd\u003eUL, CE, CSA, IECEx (variant dependent)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003ch3\u003eBackplane Interface and Temperature Compensation Behavior\u003c\/h3\u003e\n\u003cp\u003eThe 1756-CJC\/A operates as a passive thermistor-based reference element integrated into the RTB structure of ControlLogix thermocouple input modules. Temperature sensing is applied at the terminal block interface to compensate for junction voltage drift caused by ambient temperature variation. The resulting compensation value is consumed by the analog input module during A\/D conversion and thermocouple linearization. Signal integrity is dependent on stable backplane reference and correct mechanical seating within the RTB assembly.\u003c\/p\u003e\n\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\n\u003cp\u003eQ: Does the 1756-CJC\/A generate its own signal processing output?\u003cbr\u003eA: No. The module provides only cold junction reference sensing. Signal processing is performed by the connected thermocouple input module.\u003c\/p\u003e\n\u003cp\u003eQ: Is the 1756-CJC\/A electrically active on the ControlLogix backplane?\u003cbr\u003eA: It operates passively and does not consume defined backplane current as a functional I\/O module.\u003c\/p\u003e\n\u003cp\u003eQ: Can the module be installed independently without an analog input module?\u003cbr\u003eA: No. It must be installed into the RTB of a compatible thermocouple input module.\u003c\/p\u003e\n\u003chr\u003e\n\u003ch3\u003eField Installation Guidelines\u003c\/h3\u003e\n\u003cp\u003eInstall the 1756-CJC\/A directly into the RTB of the corresponding ControlLogix thermocouple input module. Ensure full mechanical seating to maintain stable thermal coupling between terminal block and compensation element. Power shall be removed from the chassis prior to installation. Maintain separation between thermocouple wiring and high-current conductors to reduce thermal and electrical coupling errors. Do not bend or stress the RTB assembly during insertion. Verify correct module pairing before energization.\u003c\/p\u003e","brand":"Allen-Bradley","offers":[{"title":"Default Title","offer_id":43572460159066,"sku":"1756-CJC\/A","price":123.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0612\/4601\/3530\/files\/1756-CJC1.jpg?v=1782790009","url":"https:\/\/www.plcmasters.com\/products\/allen-bradley-1756-cjc-a-controllogix-cold-junction-compensation-module","provider":"PLC Masters Ltd.","version":"1.0","type":"link"}