Product Overview
The Bently Nevada 990-05-XX-01-CN is a single-channel, two-wire, loop-powered vibration transmitter from the Bently Nevada 990 Series, designed to measure radial shaft vibration on rotating machinery and deliver the result as an industry-standard 4–20 mA signal directly to a PLC, DCS, or SCADA system. The 990-05-XX-01-CN accepts the input from one non-contacting 3300 NSv (5/8 in) eddy-current proximity probe and its matched extension cable, converting shaft relative vibration into a proportional current loop without requiring a separate Proximitor driver, signal conditioner, or monitoring rack.
Its defining practical feature is integration. The Proximitor driver electronics are built into the transmitter body, so there is no separate Proximitor box to buy, mount, or wire — the transmitter, probe, and cable form a complete eddy-current measurement channel. The “05” in the Bently Nevada 990-05-XX-01-CN specifies a full-scale range of 0–5 mils peak-to-peak (0–125 µm pp); the “01” specifies 35 mm DIN-rail clips; and the “CN” denotes the China-region agency-approval and connector configuration. Because the “XX” position is open, the total electrical system length — probe plus extension cable — must be specified to match the installed transducer, and the transmitter is factory-calibrated to that length.
The 990-05-XX-01-CN is aimed at OEMs and end users who need a simple, trustworthy vibration signal feeding a PLC, DCS, or SCADA system — centrifugal air compressors, small pumps, motors, and fans — rather than a full API 670 rack-based protection system such as a Bently Nevada 3500. It does not record waveform snapshots, alarms, or phase data, and it does not perform spectrum or orbit analysis; it reports shaft relative vibration amplitude continuously so that the customer’s own control platform can apply alarming and trip logic. This makes it a cost-effective choice for distributed monitoring where a full rack would be uneconomic or physically impractical.
Technical Specifications
| Parameter Name | Parameter Value |
|---|---|
| Product Model | Bently Nevada 990-05-XX-01-CN (Modification 165335-01) |
| Manufacturer | Bently Nevada (a Baker Hughes company) |
| Product Type | 990 Series Vibration Transmitter — two-wire, loop-powered, integrated Proximitor |
| Measurement Type | Radial shaft vibration (shaft relative displacement) |
| Input | 1 × non-contacting 3300 NSv (5/8 in) proximity probe + matched extension cable |
| Full-Scale Range | 0–5 mils pp (0–125 µm pp) — “05” option |
| System Length “XX” | Must be specified: 50 = 5.0 m (16.4 ft) or 70 = 7.0 m (23.0 ft), probe + cable total electrical length |
| Mounting “01” | 35 mm DIN-rail clips |
| Agency Approval “CN” | China-region approval and connector configuration |
| Output Signal | 4–20 mA DC, two-wire, proportional to vibration amplitude |
| Supply Voltage | +12 to +35 V DC at the transmitter terminals |
| Maximum Loop Resistance | 1,000 Ω including cable (at 35 V DC) |
| Current Limiting | 23 mA typical |
| Scale Factor (Prox Out) | 200 mV/mil (7.87 mV/µm) |
| Accuracy | ±1.5 % of full scale |
| Frequency Response | 5 Hz to 6,000 Hz (+0, −3 dB) |
| Linear Range (Prox Out) | 0.25 to 1.65 mm (10 to 65 mils) |
| Probe Gap (Target) | 0.5 to 1.75 mm (20 to 55 mils) for linear, full-scale operation |
| Probe Tip Material | Polyphenylene sulfide (PPS) |
| Probe Case Material | AISI 303 or 304 stainless steel |
| Probe Cable | 75 Ω coaxial, FEP-insulated, with optional FEP-jacketed flexible AISI 302 SST armor |
| Probe Target Material | AISI 4140 steel |
| Fault Output Behavior | Drives output below 3.6 mA within 100 µs on probe-circuit fault |
| Power-Up Suppression | Output held below 3.6 mA for 2–3 seconds after power-up |
| Diagnostic Output | Non-isolated PROX OUT via BNC connector and terminal block (dynamic signal + gap voltage) |
| Output Impedance (Prox Out) | 10 kΩ, calibrated for 10 MΩ load |
| PROX OUT Leadwire | BNC connector, maximum 3 m (10 ft) cable distance |
| Transmitter Operating Temperature | −35 °C to +85 °C |
| Probe Operating Temperature | −52 °C to +177 °C |
| Storage Temperature | −52 °C to +100 °C |
| Humidity | 100 % condensing, non-submerged (with coaxial connector protected) |
| Enclosure | Potted, sealed construction |
| Transmitter Weight | 0.43 kg (0.9 lbm) |
| Total System Weight | 0.82 kg (1.8 lbm) typical |