{"product_id":"siemens-3rh1921-1ca10-auxiliary-contact-block-copy","title":"Siemens 3RH1921-1CA01 Auxiliary Contact Block","description":"\u003cp\u003eThe \u003cb\u003eSiemens 3RH1921-1CA01\u003c\/b\u003e is a 1-pole, \u003cb\u003eside-mounted\u003c\/b\u003e auxiliary contact block from the legacy \u003cb\u003eSIRIUS 3RT1\/3RH1\u003c\/b\u003e series. In the Canadian elevator industry, this is a \"first-position\" block commonly found in older \u003cb\u003eMCE\u003c\/b\u003e, \u003cb\u003eThyssenKrupp\u003c\/b\u003e, or \u003cb\u003eGAL\u003c\/b\u003e controllers. It is specifically designed to snap onto the side of the older generation \u003cb\u003e3RT1\u003c\/b\u003e contactors (Sizes \u003cb\u003eS0 through S12\u003c\/b\u003e).\u003c\/p\u003e\n\u003cp\u003e\u003cb\u003eCore Specifications\u003c\/b\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cb\u003eSeries:\u003c\/b\u003e 3RH19 (Legacy SIRIUS)\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cb\u003eMounting:\u003c\/b\u003e \u003cb\u003eSide-mounted\u003c\/b\u003e (Mounts to either the left or right side)\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cb\u003eContact Configuration:\u003c\/b\u003e 0\u003cb\u003e NO \/ 1 NC\u003c\/b\u003e (One Normally closed contact)\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cb\u003eCompatibility:\u003c\/b\u003e Fits \u003cb\u003e3RT1\u003c\/b\u003e contactors and \u003cb\u003e3RH1\u003c\/b\u003e control relays\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cb\u003eTerminal Type:\u003c\/b\u003e Screw terminals (Pozi-drive)\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003chr\u003e\n\u003ch3\u003e\u003cb\u003eElevator Logic Applications (1 NC)\u003c\/b\u003e\u003c\/h3\u003e\n\u003cp\u003eBecause this block provides only a single Normally Open contact, it is typically dedicated to a specific signaling or holding task rather than a complete safety monitoring loop:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cb\u003eSeal-in \/ Holding:\u003c\/b\u003e Acting as the \"latch\" to keep the contactor coil energized after the controller pulses the start command.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cb\u003eBrake Signaling:\u003c\/b\u003e Providing a dry contact signal to the brake controller or VFD to indicate that the motor contactor is physically \"Made.\"\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cb\u003eAuxiliary Fan Control:\u003c\/b\u003e Engaging motor or cabinet cooling fans only when the main contactor is active.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cb\u003eIndicator Logic:\u003c\/b\u003e Feeding a signal to a \"Motor Running\" lamp or a diagnostic input on the elevator CPU.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003chr\u003e\n\u003ch3\u003e\u003cb\u003eInstallation \u0026amp; Mechanical Integration\u003c\/b\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cb\u003eLateral Profile:\u003c\/b\u003e This block adds approximately \u003cb\u003e10mm to the width\u003c\/b\u003e of the contactor but \u003cb\u003ezero depth\u003c\/b\u003e. This makes it the standard choice for older, shallow cabinets where front-mounted auxiliaries would prevent the cabinet door from closing.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cb\u003eSnap-On Design:\u003c\/b\u003e It clips directly onto the side of the 3RT1 frame. A mechanical link on the side of the contactor engages the block to ensure the NO contact closes precisely when the main power poles do.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cb\u003eFirst-Position Mounting:\u003c\/b\u003e The \u003cb\u003e\"2\"\u003c\/b\u003e in the prefix (\u003cb\u003e3RH1921\u003c\/b\u003e) confirms this is a first-position block. On larger S3–S12 frames, you can often \"stack\" a second-position block onto this one if more logic is required.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003chr\u003e\n\u003ch3\u003e\u003cb\u003eField Maintenance \u0026amp; Canadian Code Notes\u003c\/b\u003e\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cb\u003eLegacy Compatibility Warning:\u003c\/b\u003e This is a \u003cb\u003eLegacy\u003c\/b\u003e component. It is \u003cb\u003enot\u003c\/b\u003e compatible with the modern \u003cb\u003e3RT2\u003c\/b\u003e (Innovations) series contactors. If you are replacing a failed 3RT1 contactor with a new 3RT2, you must also replace this auxiliary block with the \u003cb\u003e3RH2921\u003c\/b\u003e equivalent.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cb\u003eB44 Safety Monitoring:\u003c\/b\u003e Per Canadian code, \"Contactor State Monitoring\" requires an \u003cb\u003eNC (Normally Closed)\u003c\/b\u003e contact to verify the contactor has dropped. Since this block is \u003cb\u003e1 NO only\u003c\/b\u003e, it cannot perform this safety function alone; it must be used in conjunction with a block that provides an NC contact (like a 3RH1921-1CA01).\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cb\u003eTerminal Integrity:\u003c\/b\u003e In older machine rooms, these legacy blocks are prone to \"contact pitting\" or oxidation. If the elevator is failing to seal-in, check the resistance across terminals \u003cb\u003e13-14\u003c\/b\u003e. If it exceeds \u003cb\u003e1–2 ohms\u003c\/b\u003e when energized, the block should be replaced.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cb\u003eTorque:\u003c\/b\u003e Ensure logic wires are torqued to \u003cb\u003e0.8–1.2 Nm\u003c\/b\u003e. Loose connections in older controllers are a frequent source of \"phantom\" faults and intermittent directional errors.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"R.A.M. Parts","offers":[{"title":"Default Title","offer_id":49783436148888,"sku":null,"price":0.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0741\/4369\/5000\/files\/rn-image_picker_lib_temp_e0e40b0f-6d08-4279-9994-f19225c9ffff.jpg?v=1771368925","url":"https:\/\/parts4rem.ca\/products\/siemens-3rh1921-1ca10-auxiliary-contact-block-copy","provider":"Parts4REM","version":"1.0","type":"link"}