Application Scenarios
A centrifugal air compressor OEM was designing a control panel for a packaged unit destined for a petrochemical plant. The customer required a vibration signal that could feed directly into the plant’s PLC without the cost and complexity of a full continuous monitoring system. The OEM specified the 990-05-70-01-01 paired with a 3300 NSv probe. The transmitter’s loop-powered design simplified wiring, and its 4-20 mA output integrated seamlessly with the PLC’s analog input card. The potted construction handled the humid compressor enclosure environment, while the Not OK/Signal Defeat circuit prevented false high readings from a loose probe connection.
In a municipal water treatment facility, a maintenance engineer needed to add vibration trending to several small pump motors without running new conduit for separate power and signal lines. The 990-05-70-01-01 was installed with 35 mm DIN rail clips inside an existing junction box. Power and signal shared the same two wires, reducing installation time. The engineer used the PROX OUT coaxial connector to periodically capture dynamic vibration data with a portable analyzer, confirming bearing condition during scheduled inspections.
Parameters
| Parameter | Value / Description |
|---|---|
| Product Model | 990-05-70-01-01 |
| Manufacturer | Bently Nevada |
| Product Category | 2-Wire Vibration Transmitter |
| Input Compatibility | 1 × 3300 NSv Proximity Probe with extension cable |
| Power Requirement | +12 to +35 Vdc at transmitter terminal |
| Signal Output | 4-20 mA, 2-wire loop-powered configuration |
| Full-Scale Option | 05 = 0-5 mils pp (0-125 μm pp) |
| System Length Option | 70 = 7.0 meters (23.0 feet) |
| Loop Accuracy | ±1.5% over specified full-scale range |
| Maximum Loop Resistance | 1,000 Ω including cable at 35 Vdc |
| Operating Temperature | -35°C to +85°C |
| Storage Temperature | -51°C to +100°C |
| Mounting Option | 01 = 35 mm DIN rail clips |
| Agency Approval | 01 = CSA Division 2 |
| Weight | 0.54 kg (transmitter), 2 kg shipping weight |
| Not OK / Signal Defeat | Output <3.6 mA within 100 μs of fault condition |
Technical Principles and Innovative Values
- Innovation Point 1: Integrated Proximitor sensor eliminates external unit. The 990-05-70-01-01 houses the Proximitor sensor inside the transmitter housing, removing the need for a separate signal conditioning module. This reduces panel space, wiring complexity, and potential failure points in the signal chain.
- Innovation Point 2: Loop-powered two-wire design. Power and signal share a single pair of wires. The 990-05-70-01-01 draws its operating power from the same 4-20 mA loop it drives, cutting installation cost and simplifying retrofit into existing PLC or DCS cabinets where spare conductors are limited.
- Innovation Point 3: Non-isolated PROX OUT for diagnostics. The front-panel coaxial connector provides a dynamic vibration signal for connecting portable analyzers and oscilloscopes. This lets technicians capture raw vibration waveforms during troubleshooting without disconnecting the 4-20 mA loop. The 990-05-70-01-01 preserves the industry-standard 200 mV/mil scale factor for direct reading on standard instruments.
- Innovation Point 4: Not OK/Signal Defeat circuit. When the proximity probe fails or its connection loosens, the 990-05-70-01-01 drives its output below 3.6 mA within 100 microseconds. This failsafe behavior prevents the control system from seeing a false high vibration reading that could trigger an unnecessary shutdown or, worse, mask a real fault.
- Innovation Point 5: Potted construction for condensing humidity. The transmitter electronics are fully encapsulated, allowing operation in environments with up to 100% condensing humidity. The 990-05-70-01-01 is rated for the damp, oily conditions often found inside compressor enclosures and coastal installations.
Reviews
There are no reviews yet.