Derivative Action in PID Control Without Noise Problems
Learn what derivative action contributes to a PID loop, why it can amplify measurement noise and setpoint changes, and how filtering, sampling, and staged tests make D tuning safer.
Manufacturer: Bently Nevada
Product No.: 990-05-70-03-05
Country of origin:United States
Product Type: Vibration Transmitter
Barcode: 8537101190
Payment: T/T, Western Union
Weight: 820g
Dimensions: 53.3 mm x 73.9 mm x 100.1 mm
Shipping port: Xiamen
Warranty: 12 months
The 990 Vibration Transmitter is a two-wire, loop-powered vibration monitoring device designed for centrifugal air compressors, pumps, motors, and fans requiring a proportional 4 to 20 mA vibration output for machinery control systems. Bently Nevada developed this transmitter primarily for OEM machinery integration where continuous vibration trending and basic protection functions are required.
The transmitter accepts input from a 3300 NSv proximity probe and matching extension cable system. It conditions the probe signal into a peak-to-peak vibration amplitude signal and transmits a proportional 4 to 20 mA output to PLC, DCS, or other automation control systems.
The integrated Proximitor sensor design eliminates the need for an external proximitor module, simplifying installation in compact machinery areas with limited mounting clearance. The unit also provides a non-isolated PROX OUT signal for machinery diagnostics and waveform analysis.
The 990-05-70-03-05 configuration includes a 7.0 m transducer system length, DIN rail and screw mounting hardware, and hazardous area approvals suitable for Division 2 and ATEX installations.
| Model Code | Description |
|---|---|
| 990 | Vibration Transmitter |
| -05 | 0-5 mils pp (0-125 um pp) |
| -70 | 7.0 metres (23.0 feet) |
| -03 | DIN clips and screws |
| -05 | CSA Division 2, ATEX Zone 0, ATEX Zone 2 and ABS maritime approval |
| Category | Specification |
|---|---|
| Manufacturer | Bently Nevada |
| Product Model | 990-05-70-03-05 |
| Product Type | 990 Vibration Transmitter |
| Country of Origin | U.S.A |
| Input Type | 3300 NSv Proximity Probe and Extension Cable |
| Power Supply | +12 to +35 Vdc |
| Signal Output | 4 to 20 mAdc |
| Configuration | 2-wire loop-powered |
| Loop Accuracy | +/-1.5% full scale |
| Maximum Loop Resistance | 1000 Ohm at 35 Vdc |
| Current Limiting | 23 mA typical |
| Frequency Response | 5 Hz to 6000 Hz (+0, -3 dB) |
| Probe Gap Range | 0.5 to 1.75 mm |
| Prox Out Output Impedance | 10 kOhm |
| Prox Out Linear Range | 1.4 mm |
| Incremental Scale Factor | 7.87 mV/um (200 mV/mil) +/-6.5% typical |
| Temperature Stability | Within +/-10% from 0 degC to +70 degC |
| Minimum Target Size | 9.5 mm diameter |
| Maximum Diagnostic Cable Length | 3 m |
| Operating Temperature | -35 degC to +85 degC |
| Storage Temperature | -52 degC to +100 degC |
| Probe Operating Temperature | -52 degC to +177 degC |
| Probe Storage Temperature | -52 degC to +177 degC |
| Relative Humidity | 100% condensing, non-submerged |
| Probe Tip Material | Polyphenylene sulfide (PPS) |
| Probe Case Material | AISI 303 or 304 stainless steel |
| Probe Cable Type | 75 Ohm coaxial FEP insulated |
| Optional Cable Armor | Flexible AISI 302 stainless steel |
| Tensile Strength | 222 N maximum |
| Dimensions (H x W x D) | 53.3 mm x 73.9 mm x 100.1 mm |
| Body Height | 42.6 mm |
| Mounting Hole Distance | 63.5 mm x 69.9 mm |
| Mounting Hole Diameter | 5.8 mm |
| Transmitter Weight | 0.43 kg |
| Total System Weight | 0.82 kg |
| Connector Pin | Function |
|---|---|
| PROX OUT | Dynamic vibration and gap voltage output |
| COM | Common reference terminal |
| TEST Input | Loop signal verification input |
| 4-20 mA Loop | Process control system output |
| Power Input | +12 to +35 Vdc supply |
| Certification | Description |
|---|---|
| CSA Division 2 | Hazardous area approval |
| ATEX Zone 0 | Hazardous area approval |
| ATEX Zone 2 | Hazardous area approval |
| ABS | Maritime approval |
What is the primary function of the 990 transmitter?
It converts proximity probe vibration signals into a proportional 4 to 20 mA output for machinery monitoring systems.
Which probe system is compatible with this transmitter?
The unit supports Bently Nevada 3300 NSv proximity probes and matching extension cables.
Can the transmitter provide dynamic vibration signals?
Yes. The PROX OUT connector provides a dynamic transducer signal for diagnostics.
Is the transmitter loop powered?
Yes. It operates as a two-wire loop-powered device.
What is the supported frequency range?
The frequency response is 5 Hz to 6000 Hz.
Can this unit be used in hazardous areas?
Yes. This configuration includes CSA Division 2 and ATEX approvals.
Does the transmitter require an external proximitor module?
No. The Proximitor sensor is integrated into the transmitter.
What is the required supply voltage?
The operating supply range is +12 to +35 Vdc.
How does the NOT OK function operate?
The output drops below 3.6 mA when a probe fault or signal issue occurs.
What mounting methods are supported?
The unit supports DIN rail mounting and screw mounting.
Can the 4-20 mA signal be used for vibration phase analysis?
No. The analog output only provides peak-to-peak vibration trending data.
What diagnostic equipment requires the test adapter?
Grounded AC-powered oscilloscopes and analyzers should use the 122115-01 Test Adapter.
What humidity level can the transmitter withstand?
The transmitter supports 100% condensing humidity in non-submerged conditions.
What is the maximum diagnostic cable distance from PROX OUT?
The recommended maximum cable distance is 3 meters.
Is the transmitter suitable for System 1 diagnostics?
No. It is intended for overall vibration trending rather than full dynamic diagnostic systems.
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| Color pattern |
Greyish White
Black
|
| Country of origin |
United States
|