990 2-Wire Vibration Transmitter | Bently Nevada | 990-04-50-01-00

Specifications:

Input

• Accepts 1 non-contacting 3300 NSv Proximity Probe and extension cable.

Power

• Requires +12 to +35 Vdc input at the transmitter terminal.

4 to 20 mA Signal Output

• 4 to 20 mAdc over specified full-scale range in 2-wire configuration.

4 to 20 mA Loop Accuracy

• Within ±1.5% over specified full-scale range.
• Accuracy is rated from the TEST signal input to the voltage measured across a 250  loop resistance.

Probe Gap

• Probe must be gapped between 0.5 and 1.75 mm (20 and 55 mils) from target to ensure full-scale range.

Maximum Loop Resistance

• 1,000  including cable at 35 Vdc.

Current Limiting

• 23 mA typical.

Zero and Span

• Non-interacting external adjustments.

NOT OK/Signal Defeat

• Signal output will go to less than 3.6 mA within 100 µs after a Not OK condition occurs.
• Signal output is restored within 2-3 seconds after the Not OK condition is removed.

Power-up Inhibit

• Signal output stays at less than 3.6 mA (NOT O.K.) for 2 to 3 seconds after power is applied.
• The purpose is to signal that the device is not yet ready. Transients may be observed when the device goes O.K.

Proximitor Sensor Output

• Compatible with ungrounded, portable test equipment.
• When using grounded, AC-powered test equipment, use the 122115-01 Test Adapter for signal isolation.

Output Impedance

• Prox Out has a 10 k output impedance calibrated for a 10 M load.

Prox Out Linear Range

• 1.4 mm (55 mils). Begins at approximately 0.25 mm (10 mils) from target surface.

Prox Out Incremental Scale Factor

• 7.87 mV/µm (200 mV/mil) ± 6.5% typical including interchangeability errors when measured in increments of 0.25 mm (10 mils) over the linear range.