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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, looppowered 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 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 μm pp)
0 5 0-5 mils pp (0-125 μm 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