{"product_id":"abb-tu891-compact-terminal-unit","title":"ABB TU891 Compact Terminal Unit","description":"\u003cp\u003eThe \u003cstrong\u003eABB TU891\u003c\/strong\u003e, also cataloged as the \u003cstrong\u003eTU891\u003c\/strong\u003e Compact Terminal Unit, operates as a dedicated hardware component for localized process wiring termination within S800 I\/O network platforms.\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\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\u003eModel\u003c\/td\u003e\n\u003ctd\u003eTU891\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBrand\u003c\/td\u003e\n\u003ctd\u003eABB\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eArticle Number\u003c\/td\u003e\n\u003ctd\u003e3BSC840157R1\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOrigin\u003c\/td\u003e\n\u003ctd\u003eSweden\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eProduct Type\u003c\/td\u003e\n\u003ctd\u003eTerminal Blocks\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eChannel Capacity\u003c\/td\u003e\n\u003ctd\u003e8 independent processing channels\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eNominal Voltage\u003c\/td\u003e\n\u003ctd\u003e24 V\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSystem Loop Redundancy\u003c\/td\u003e\n\u003ctd\u003eSingle I\/O configuration\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCompatible I\/O Modules\u003c\/td\u003e\n\u003ctd\u003eAI890, AI893, AI895, AO890, AO895, DI890, DO890\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePhysical Process Terminals\u003c\/td\u003e\n\u003ctd\u003e27 gray terminals\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMaximum Current per I\/O Channel\u003c\/td\u003e\n\u003ctd\u003e2 A\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSolid Wire Size Range (Process)\u003c\/td\u003e\n\u003ctd\u003e0.2 to 4 mm2\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eStranded Wire Size Range (Process)\u003c\/td\u003e\n\u003ctd\u003e0.2 to 2.5 mm2 (24 to 12 AWG)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePower Supply Wire Size Range\u003c\/td\u003e\n\u003ctd\u003e0.25 to 2.5 mm2 (24 to 14 AWG)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRecommended Terminal Screw Torque\u003c\/td\u003e\n\u003ctd\u003e0.5 to 0.6 Nm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDielectric Test Voltage\u003c\/td\u003e\n\u003ctd\u003e500 V AC\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMechanical Mounting Format\u003c\/td\u003e\n\u003ctd\u003eHorizontal DIN-rail installation\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWidth Dimension\u003c\/td\u003e\n\u003ctd\u003e64 mm (including connector), 58.5 mm (installed edge-to-edge)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDepth Dimension\u003c\/td\u003e\n\u003ctd\u003e58 mm (chassis base), 106 mm (including terminals)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eHeight Dimension\u003c\/td\u003e\n\u003ctd\u003e194 mm (including retention latch)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e0.17 kg (0.37 lbs)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMaximum Operational Temperature\u003c\/td\u003e\n\u003ctd\u003e55 deg C under full electrical load\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/figure\u003e\n\u003ch3\u003eProfinet \/ EtherNet\/IP Deterministic Networks and Driver Integration\u003c\/h3\u003e\n\u003cp\u003eThe compact terminal unit mounts directly onto standard DIN rails to establish electrical pass-through continuity between field instrumentation and matching S800 intrinsically safe I\/O modules. It bridges raw analog or discrete loop signals directly to the internal processing layer, matching backplane bus communication velocity baselines through physical pin engagement. Channel parameters route seamlessly through host communication heads over Profinet or EtherNet\/IP deterministic networks, enabling independent node diagnostics without introducing localized processing latency. This dense mechanical packaging supports flexible I\/O density scaling routines, while full firmware flash compatibility at the parent I\/O module tier ensures seamless channel configuration updates across modular process nodes.\u003c\/p\u003e\n\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\n\u003cp\u003eQ: Which specific intrinsic safety or standard S800 I\/O cards mate with this terminal unit?\u003c\/p\u003e\n\u003cp\u003eA: The hardware is engineered explicitly to interface with ABB 800xA series extended automation I\/O cards, including the AI890, AI893, and AI895 analog input modules, the AO890 and AO895 analog output units, and the DI890 or DO890 discrete digital cards.\u003c\/p\u003e\n\u003cp\u003eQ: What are the engineering consequences of exceeding the 0.6 Nm terminal torque specification?\u003c\/p\u003e\n\u003cp\u003eA: Over-torquing the terminal clamping screws beyond 0.6 Nm can strip the internal threads or fracture the SMT solder joints connecting the terminal cage to the internal trace distribution plane, introducing intermittent open-circuit faults into the processing loop.\u003c\/p\u003e","brand":"ABB","offers":[{"title":"Default Title","offer_id":47600095166654,"sku":"TU891","price":100.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0725\/1145\/5422\/files\/screenshot_2026-06-03_10-19-31_75132d01-14ea-4882-8f76-e306188c3727.png?v=1780453221","url":"https:\/\/www.autooiltech.com\/products\/abb-tu891-compact-terminal-unit","provider":"AutoOilTech Limited","version":"1.0","type":"link"}