Bently Nevada 990 Vibration Transmitter
990本特利振動變送器常用型號：
990-05-50-02-01 / 990-05-50-02-00
990-04-50-02-00 / 990-04-50-01-00
990-04-70-01-00 / 990-05-50-01-05
990-05-70-02-00 / 990-05-70-01-01

Description
The 990 Vibration Transmitter is intended primarily for the original equipment manufacturers (OEMs) of centrifugal air compressors or small pumps, motors, or fans who prefer to provide a simple 4 to 20 mA proportional vibration signal as the input to their machinery control system. The transmitter is a 2-wire, loop-powered device that accepts input from our 3300 NSv* proximity probe and its matching extension cable (available in 5 m and 7 m system length options). The transmitter conditions the signal into appropriate peak-to-peak vibration amplitude engineering units, and provides this value as a proportional 4 to 20 mA industry-standard signal as the input to the control system where machinery protection alarming and logic occurs1.

The 990 transmitter provides the following notable features:
?Integrated Proximitor* Sensor requires no external unit
?Non-isolated “PROX OUT" and "COM" terminals plus a coaxial connector to provide a dynamic vibration and gap voltage signal output for diagnostics2.
?Non-interacting zero and span potentiometers under the Transmitter label supports loop adjustment.
?Test Input pin for quick verification of loop signal output, using a function generator as the input.
?A Power-up Inhibit circuit eliminates signal errors due to line voltage transients.
?A Not OK/Signal Defeat circuit prevents high outputs or false alarms due to a faulty proximity probe or loose connection.
?Choice of DIN-rail clips or bulkhead mounting screws as standard options simplifies mounting.
?Potted construction for high humidity (up to 100% condensing) environments.
?Compatibility with 3300 NSv proximity probe allows transducer installation in small areas with minimal clearance, typical of centrifugal air compressors.

Ordering Information
990-AXX-BXX-CXX-DXX

A: Full-scale Option
0 4 0-4 mils pp (0-100 mm pp)
0 5 0-5 mils pp (0-125 mm pp)

B: System Length Option
5 0 5.0 metres (16.4 feet)
7 0 7.0 metres (23.0 feet)

C: Mounting Option
0 1 35 mm DIN rail clips
0 2 Bulkhead screws
0 3 DIN clips and screws

D: Agency Approval Option
0 0 Not required
0 1 CSA Division 2
0 5 CSA Division 2 , ATEX Zone 0, ATEX Zone 2 and includes ABS maritime approval