Bently Nevada 991 Thrust Transmitter
991本特利軸位移變送器常用型號：
991-06-50-01-00 991-06-70-01-00
991-25-50-01-00 991-25-70-01-00
991-06-50-01-CN 991-06-70-01-CN
991-25-50-01-CN 991-25-70-01-CN

Description
The 991 Thrust 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 axial displacement (thrust) 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 engineering units proportional to the shaft’s axial position1, and provides it as a 4 to 20 mA industry-standard signal for input to the control system where machinery protection alarming and logic occurs2.

The 991 transmitter provides the following notable features:
Integrated Proximitor* Sensor requires no external unit
Non-isolated “PROX OUT " and "COM" terminals plus a coaxial connector provide a dynamic vibration and gap voltage signal output for diagnostics3.
Non-interacting zero and span potentiometers under the Transmitter label supports loop adjustment.
Test Input pin allows quick verification of loop signal output, using a variable DC voltage source 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
991-AXX-BXX-CXX-DXX

A: Full-scale Option
0 6   0.6 -0- 0.6 mm
2 5   25-0-25 mils

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


OEM定制型號：

991-01-XX-01-00 (W/MOD 288865-01)
991-01-XX-01-00 (W/MOD 284318-01)
991-01-XX-01-05 (W/MOD 284318-01)
991-01-XX-02-00 (W/MOD 284318-01)
991-06-XX-01-00 (W/MOD 169955-01)
991-06-XX-01-00 (W/MOD 164113-01)
991-06-XX-01-CN (W/MOD 169955-01)
991-25-XX-02-00 (W/MOD 164113-01)