{"product_id":"bently-nevada-991-25-50-03-01-industrial-automation-module","title":"Bently Nevada 991-25-50-03-01 Industrial Automation Module","description":"\u003ch2\u003eProduct Overview\u003c\/h2\u003e\u003cp\u003eThe Bently Nevada 991-25-50-03-01 Probe Vibration Transmitter is a compact, DIN-rail mounted device designed for continuous axial thrust monitoring in rotating machinery. This industrial automation module converts non-contacting proximity probe signals into a standard 4-20 mA current loop output, providing real-time data for predictive maintenance and machinery protection systems.\u003c\/p\u003e\u003cp\u003ePart of the reliable 991 series, the \u003cstrong\u003e991-25-50-03-01\u003c\/strong\u003e offers a full-scale range of 25-0-25 mils and includes a 5.0-meter system length cable. Its robust construction ensures dependable operation in harsh industrial environments, with operating temperatures from -35°C to +85°C.\u003c\/p\u003e\u003ch2\u003eTechnical Specifications\u003c\/h2\u003e\u003cp\u003eThe \u003cstrong\u003eBently Nevada 991-25-50-03-01\u003c\/strong\u003e delivers critical performance parameters for accurate vibration monitoring:\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eOutput Signal:\u003c\/strong\u003e 4-20 mA (2-wire configuration)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eLoop Accuracy:\u003c\/strong\u003e ±1.5% over full scale (typical)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaximum Loop Resistance:\u003c\/strong\u003e 1,000 Ω at 35 Vdc\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCurrent Limiting:\u003c\/strong\u003e 23 mA typical\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePower Supply:\u003c\/strong\u003e +12 to +35 Vdc input at transmitter terminal\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eLinear Range:\u003c\/strong\u003e 0.25 to 1.65 mm for Prox Out; suitable for 0.6-0-0.6 mm or 25-0-25 mils current loop linear ranges\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOperating Temperature:\u003c\/strong\u003e -35°C to +85°C (-31°F to +185°F)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eStorage Temperature:\u003c\/strong\u003e -51°C to +100°C (-60°F to +212°F)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWeight:\u003c\/strong\u003e 0.43 kg (0.9 lbm)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMounting:\u003c\/strong\u003e DIN rail with DIN clips and screws (option 03)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAgency Approval:\u003c\/strong\u003e CSA Division 2 (option 01)\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eIndustry Applications\u003c\/h2\u003e\u003cp\u003eThe \u003cstrong\u003e991-25-50-03-01\u003c\/strong\u003e is specifically designed for axial thrust monitoring in large rotating equipment such as steam turbines, compressors, and pumps. Its ability to output a consistent 4-20 mA signal makes it an ideal component for integration with PLCs, DCS, and vibration monitoring systems.\u003c\/p\u003e\u003cp\u003eIn a typical petrochemical plant application, the transmitter mounts on a DIN rail near the machinery, accepting input from a single 3300 NSv proximity probe. The Not OK\/Signal Defeat feature ensures that if a fault occurs, the output drops below 3.6 mA within 100 µs, triggering alarms and preventing false readings.\u003c\/p\u003e\u003ch2\u003eInstallation \u0026amp; Setup Guidance\u003c\/h2\u003e\u003cp\u003eMount the \u003cstrong\u003eBently Nevada 991-25-50-03-01\u003c\/strong\u003e on a standard DIN rail using the included DIN clips and screws. Ensure the power supply provides +12 to +35 Vdc at the transmitter terminals. Connect the 3300 NSv proximity probe and extension cable to the input. The 4-20 mA output connects in a 2-wire loop, with maximum loop resistance of 1,000 Ω at 35 Vdc.\u003c\/p\u003e\u003cp\u003eNon-interacting external adjustments allow easy zero and span calibration. Always verify the linear range matches the probe gap and mechanical setup before commissioning.\u003c\/p\u003e\u003ch2\u003eMaintenance \u0026amp; Reliability\u003c\/h2\u003e\u003cp\u003eRoutine inspection of the \u003cstrong\u003e991-25-50-03-01\u003c\/strong\u003e should focus on verifying the integrity of the DIN rail mounting, cable connections, and probe condition. The transmitter’s operating range covers -35°C to +85°C, so ensure the ambient temperature stays within limits. The Not OK\/Signal Defeat feature enhances system reliability by automatically signaling faults, reducing unplanned downtime.\u003c\/p\u003e\u003cp\u003eNo internal adjustments or periodic recalibration is needed under normal operation. However, testing the loop accuracy periodically (using the TEST signal input) ensures continued performance within the ±1.5% specification.\u003c\/p\u003e\u003ch2\u003eTroubleshooting \u0026amp; Common Issues\u003c\/h2\u003e\u003cp\u003eIf the 4-20 mA output remains below 3.6 mA, the transmitter is likely in a Not OK state. Check the proximity probe connection, power supply voltage, and loop resistance. The Current Limiting function (23 mA typical) prevents damage during short circuits. If output drifts, verify the zero and span adjustments have not been disturbed. The transmitter recovers from a Not OK condition within 0.1 seconds after the fault is cleared.\u003c\/p\u003e\u003ch2\u003eSelection Guide \u0026amp; Purchasing Advice\u003c\/h2\u003e\u003cp\u003eWhen ordering the \u003cstrong\u003eBently Nevada 991-25-50-03-01\u003c\/strong\u003e, confirm the full-scale option (-25 for 25-0-25 mils), system length (-50 for 5.0 meters), and agency approval (01 for CSA Division 2). This unit is available from ubest101, a reliable supplier of industrial automation spares. Ensure your system uses a compatible 3300 NSv proximity probe and extension cable.\u003c\/p\u003e","brand":"Bently Nevada","offers":[{"title":"Default","offer_id":44416875593827,"sku":"991-25-50-03-01","price":227.0,"currency_code":"USD","in_stock":true}],"url":"https:\/\/www.plcsourcepro.com\/products\/bently-nevada-991-25-50-03-01-industrial-automation-module","provider":"PLC Source PRO","version":"1.0","type":"link"}