{"product_id":"bently-nevada-991-25-50-03-05-991-thrust-transmitter","title":"Bently Nevada 991-25-50-03-05 991 Thrust Transmitter","description":"\u003cp\u003e\u003cstrong\u003e991 Thrust Transmitter 991-25-50-03-05\u003c\/strong\u003e is a 2-wire, loop-powered axial displacement transmitter designed for continuous thrust position measurement using a 3300 NSv proximity probe and matching extension cable system. The transmitter integrates the Proximitor sensor internally and converts eddy-current scaling signals into a proportional 4 to 20 mA output for machinery control systems monitoring rotor dynamics and shaft axial position. The unit provides non-isolated PROX OUT and COM terminals for dynamic vibration and gap voltage diagnostics, incorporates Not OK signal defeat circuitry for fault suppression, and supports DIN-rail or bulkhead mounting in high-humidity industrial environments.\u003c\/p\u003e\n\u003ch3\u003eOrdering Information\u003c\/h3\u003e\n\u003ctable\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd data-row=\"1\"\u003eSuffix Code Option \/ Parameter Technical Description\u003c\/td\u003e\n\u003ctd data-row=\"1\"\u003e\u003c\/td\u003e\n\u003ctd data-row=\"1\"\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd data-row=\"2\"\u003e-25\u003c\/td\u003e\n\u003ctd data-row=\"2\"\u003eFull-scale Option\u003c\/td\u003e\n\u003ctd data-row=\"2\"\u003e25-0-25 mils\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd data-row=\"3\"\u003e-50\u003c\/td\u003e\n\u003ctd data-row=\"3\"\u003eSystem Length Option\u003c\/td\u003e\n\u003ctd data-row=\"3\"\u003e5.0 meters (16.4 feet)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd data-row=\"4\"\u003e-03\u003c\/td\u003e\n\u003ctd data-row=\"4\"\u003eMounting Option\u003c\/td\u003e\n\u003ctd data-row=\"4\"\u003eDIN clips and screws\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd data-row=\"5\"\u003e-05\u003c\/td\u003e\n\u003ctd data-row=\"5\"\u003eAgency Approval Option\u003c\/td\u003e\n\u003ctd data-row=\"5\"\u003eCSA Division 2, ATEX Zone 0, ATEX Zone 2, ABS maritime approval\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003ch3\u003eHardware Specifications\u003c\/h3\u003e\n\u003ctable\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd data-row=\"1\"\u003eParameter Specification\u003c\/td\u003e\n\u003ctd data-row=\"1\"\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd data-row=\"2\"\u003eProduct Type\u003c\/td\u003e\n\u003ctd data-row=\"2\"\u003eAxial Position Thrust Transmitter\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd data-row=\"3\"\u003eInput Signal\u003c\/td\u003e\n\u003ctd data-row=\"3\"\u003eOne 3300 NSv proximity probe with extension cable\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd data-row=\"4\"\u003ePower Supply\u003c\/td\u003e\n\u003ctd data-row=\"4\"\u003e+12 to +35 VDC\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd data-row=\"5\"\u003eOutput Signal\u003c\/td\u003e\n\u003ctd data-row=\"5\"\u003e4 to 20 mADC\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd data-row=\"6\"\u003eSignal Configuration\u003c\/td\u003e\n\u003ctd data-row=\"6\"\u003e2-wire loop-powered\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd data-row=\"7\"\u003eLoop Accuracy\u003c\/td\u003e\n\u003ctd data-row=\"7\"\u003eWithin ±1.5% of full scale typical\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd data-row=\"8\"\u003eAccuracy Reference\u003c\/td\u003e\n\u003ctd data-row=\"8\"\u003eMeasured across 250 Ohm loop resistance\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd data-row=\"9\"\u003eMaximum Loop Resistance\u003c\/td\u003e\n\u003ctd data-row=\"9\"\u003e1,000 Ohm at 35 VDC\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd data-row=\"10\"\u003eCurrent Limiting\u003c\/td\u003e\n\u003ctd data-row=\"10\"\u003e23 mA typical\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd data-row=\"11\"\u003eZero Adjustment\u003c\/td\u003e\n\u003ctd data-row=\"11\"\u003eExternal non-interacting potentiometer\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd data-row=\"12\"\u003eSpan Adjustment\u003c\/td\u003e\n\u003ctd data-row=\"12\"\u003eExternal non-interacting potentiometer\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd data-row=\"13\"\u003eNot OK Response Time\u003c\/td\u003e\n\u003ctd data-row=\"13\"\u003eLess than 100 µs\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd data-row=\"14\"\u003eOutput Recovery Time\u003c\/td\u003e\n\u003ctd data-row=\"14\"\u003eLess than 0.1 s\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd data-row=\"15\"\u003eDynamic Signal Output\u003c\/td\u003e\n\u003ctd data-row=\"15\"\u003eNon-isolated PROX OUT\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd data-row=\"16\"\u003eRecommended Isolation Adapter\u003c\/td\u003e\n\u003ctd data-row=\"16\"\u003e122115-01 Test Adapter\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd data-row=\"17\"\u003eOperating Temperature\u003c\/td\u003e\n\u003ctd data-row=\"17\"\u003e-35 °C to +85 °C\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd data-row=\"18\"\u003eStorage Temperature\u003c\/td\u003e\n\u003ctd data-row=\"18\"\u003e-51 °C to +100 °C\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd data-row=\"19\"\u003eProbe Operating Temperature\u003c\/td\u003e\n\u003ctd data-row=\"19\"\u003e-52 °C to +177 °C\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd data-row=\"20\"\u003eProbe Storage Temperature\u003c\/td\u003e\n\u003ctd data-row=\"20\"\u003e-52 °C to +177 °C\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd data-row=\"21\"\u003eRelative Humidity\u003c\/td\u003e\n\u003ctd data-row=\"21\"\u003e100% condensing, non-submerged\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd data-row=\"22\"\u003eTransducer Tip Material\u003c\/td\u003e\n\u003ctd data-row=\"22\"\u003ePolyphenylene sulfide (PPS)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd data-row=\"23\"\u003eProbe Case Material\u003c\/td\u003e\n\u003ctd data-row=\"23\"\u003eAISI 303 or 304 stainless steel\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd data-row=\"24\"\u003eProbe Cable Type\u003c\/td\u003e\n\u003ctd data-row=\"24\"\u003e75 Ohm coaxial FEP insulated\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd data-row=\"25\"\u003eOptional Cable Armor\u003c\/td\u003e\n\u003ctd data-row=\"25\"\u003eFlexible AISI 302 stainless steel\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd data-row=\"26\"\u003eTensile Strength\u003c\/td\u003e\n\u003ctd data-row=\"26\"\u003e222 N (50 lbf) maximum\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd data-row=\"27\"\u003eTransmitter Weight\u003c\/td\u003e\n\u003ctd data-row=\"27\"\u003e0.43 kg\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd data-row=\"28\"\u003eTypical System Weight\u003c\/td\u003e\n\u003ctd data-row=\"28\"\u003e0.82 kg\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd data-row=\"29\"\u003eProbe Thread Options\u003c\/td\u003e\n\u003ctd data-row=\"29\"\u003e1\/4-28, 3\/8-24, M8x1, M10x1\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd data-row=\"30\"\u003eMaximum Thread Engagement 1\/4-28\u003c\/td\u003e\n\u003ctd data-row=\"30\"\u003e0.375 in\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd data-row=\"31\"\u003eMaximum Thread Engagement 3\/8-24\u003c\/td\u003e\n\u003ctd data-row=\"31\"\u003e0.563 in\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd data-row=\"32\"\u003eMaximum Thread Engagement M8x1\u003c\/td\u003e\n\u003ctd data-row=\"32\"\u003e12 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd data-row=\"33\"\u003eMaximum Thread Engagement M10x1\u003c\/td\u003e\n\u003ctd data-row=\"33\"\u003e15 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003ch3\u003eEngineering Notes\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eThrust Monitoring Limitations:\u003c\/strong\u003e Unlike continuous monitoring racks, the 991 transmitter cannot perform Timed OK channel defeat, Danger Bypass, or Trip Multiply functions. Connected PLCs or DCSs are not compatible with plant-wide diagnostic software like System 1 or Rule Paks.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eProbe Gap Calibration:\u003c\/strong\u003e Accurate probe physical gap adjustment is critical. Incorrect target gap settings prevent the loop from reaching full-scale limits in either the normal or counter directions, which deactivates machinery protection.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTarget Materials:\u003c\/strong\u003e All eddy-current scaling specifications are calibrated using an AISI 4140 steel target. Other target materials will alter the loop accuracy and response characteristics.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaximum Thread Engagement:\u003c\/strong\u003e When mounting the probe, the maximum thread engagement must not exceed 1.5 times the nominal thread diameter (0.375 in for 1\/4-28 threads, 0.563 in for 3\/8-24 threads, 12 mm for M8x1, and 15 mm for M10x1).\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eField Guidelines\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eDiagnostic Polarity and Signal Isolation:\u003c\/strong\u003e The PROX OUT coaxial signal is not isolated from the 4 to 20 mA loop current. Connecting AC-powered oscilloscopes or analyzers directly can cause ground loops and fault alarms; use a 122115-01 \/ 990\/991 Test Adapter to invert and isolate the signal while maintaining standard polarity conventions.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCoaxial Connector Insulation:\u003c\/strong\u003e Ensure all coaxial connections between the 3300 NSv probe and the extension cable are clean, dry, and wrapped with self-mating silicone tape to maintain 100% condensing humidity protection.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eShield Grounding:\u003c\/strong\u003e Terminal 3 (COM) must be tied to the loop return or system ground at a single point. Keep instrument cable shields continuous up to the termination point and isolate them from the field housing to prevent electrical noise interference on the loop.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eField Adjustment Routing:\u003c\/strong\u003e Use the non-interacting zero and span potentiometers located under the transmitter label for minor loop calibration. For verification, a variable DC voltage source can be applied to the Test Input pin to confirm loop output current.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eTechnical \u0026amp; Procurement FAQ\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003eQ: Can the 991 transmitter operate without an external Proximitor sensor?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eA: Yes. The transmitter contains an integrated Proximitor sensor and directly accepts a 3300 NSv probe input.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eQ: Is the PROX OUT signal isolated from the loop output?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eA: No. The PROX OUT terminal is non-isolated and should be connected through the 122115-01 Test Adapter when using grounded AC-powered test equipment.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eQ: Which probe system lengths are supported by the 991-25-50-03-05 configuration?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eA: The specified configuration supports a 5.0 meter 3300 NSv probe and extension cable system length.\u003c\/p\u003e","brand":"Bently Nevada","offers":[{"title":"Default Title","offer_id":52666741883243,"sku":"991-25-50-03-05","price":100.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0953\/3227\/0443\/files\/bently-nevada-991-25-50-03-05-thrust-transmitter-5xhxta0jxjj_c6629be5-70ed-4b84-bd5f-c922465d505a.jpg?v=1765446881","url":"https:\/\/www.plcprotech.com\/products\/bently-nevada-991-25-50-03-05-991-thrust-transmitter","provider":"PLC ProTech Ltd.","version":"1.0","type":"link"}