{"product_id":"bently-nevada-991-25-50-02-05-probe-vibration-transmitter","title":"Bently Nevada 991-25-50-02-05 Probe Vibration Transmitter","description":"\u003ch2\u003eProduct Overview\u003c\/h2\u003e\u003cp\u003eWhen unplanned shutdowns threaten your rotating machinery, the Bently Nevada 991-25-50-02-05 Probe Vibration Transmitter delivers immediate fault detection. Designed specifically for axial (thrust) position monitoring, this transmitter converts proximity probe signals into a 4-20 mA loop output, providing continuous, precise data to your control system. The integrated Not OK\/Signal Defeat feature ensures the output drops below 3.6 mA within 100 microseconds of a fault condition, enabling rapid safety interlocks. Engineered with a DIN rail mount and accepting a single 3300 NSv proximity probe, the 991-25-50-02-05 simplifies installation while maintaining the high reliability expected from Bently Nevada.\u003c\/p\u003e\u003ch2\u003eTechnical Specifications\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eOutput signal:\u003c\/strong\u003e 4-20 mA (2-wire configuration) over specified full-scale range\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePower input:\u003c\/strong\u003e +12 to +35 Vdc 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\u003eAccuracy:\u003c\/strong\u003e Within ±1.5% over specified full scale range (typical) measured from TEST signal to voltage across 250 Ω loop resistance\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaximum loop resistance:\u003c\/strong\u003e 1,000 Ω including cable 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\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\u003eAgency approvals:\u003c\/strong\u003e CSA Division 2, ATEX Zone 0, ATEX Zone 2, ABS maritime approval\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eReal-World Applications\u003c\/h2\u003e\u003cp\u003eThe 991-25-50-02-05 excels in axial thrust monitoring of large rotating equipment such as steam turbines, centrifugal compressors, and axial pumps. In a power generation environment, the transmitter continuously measures thrust bearing wear and instantly signals a Not OK condition if the rotor shifts beyond safe limits. The 4-20 mA output interfaces directly with PLCs or DCS modules, such as those from Allen-Bradley or Siemens, enabling immediate alarm or trip actions. For reliability engineers, the 1,000 Ω loop resistance capability supports long cable runs in industrial plants without signal degradation.\u003c\/p\u003e\u003ch2\u003eMaintenance \u0026amp; Reliability\u003c\/h2\u003e\u003cp\u003eThe Bently Nevada 991-25-50-02-05 transmitter requires minimal routine maintenance. Periodic inspection of the DIN rail mounting and probe connection is recommended every 12 months. Because the Not OK circuit activates within 100 μs, false trips are avoided while real faults are captured instantly. The non-interacting zero and span adjustments allow on-site calibration without shutdown. For maximum uptime, verify the loop supply voltage stays within +12 to +35 Vdc and that the loop resistance does not exceed the 1,000 Ω threshold. The wide operating temperature range (-35°C to +85°C) ensures reliable performance in harsh environments.\u003c\/p\u003e\u003ch2\u003eTroubleshooting Guide\u003c\/h2\u003e\u003cp\u003eIf the 4-20 mA output reads below 3.6 mA, a Not OK condition exists — check the probe tip gap and extension cable integrity. Should the output stay at 23 mA (current limit), verify the loop supply voltage is not excessive or the loop resistance is not too low. For erratic readings, confirm the zero and span potentiometers are not disturbed and that the proximity probe is compatible with the 3300 NSv series. Always consult the manufacturer documentation for detailed diagnostics.\u003c\/p\u003e\u003ch2\u003eSelection Guide \u0026amp; Purchasing Advice\u003c\/h2\u003e\u003cp\u003eBefore ordering the Bently Nevada 991-25-50-02-05, confirm the full-scale option aligns with your measurement range: this unit is configured as -25 (25-0-25 mils) with a system length of 5.0 meters (16.4 feet). The mounting option 02 uses bulkhead screws; verify your panel or junction box accommodates this. For additional probes or extension cables, contact ubest101 for compatible accessories. PLC Source PRO stocks this transmitter and can provide fast shipping for critical spares.\u003c\/p\u003e","brand":"Bently Nevada","offers":[{"title":"Default","offer_id":44416873005155,"sku":"991-25-50-02-05","price":280.0,"currency_code":"USD","in_stock":true}],"url":"https:\/\/www.plcsourcepro.com\/products\/bently-nevada-991-25-50-02-05-probe-vibration-transmitter","provider":"PLC Source PRO","version":"1.0","type":"link"}