Thrust Transmitter | 991-01-XX-01-00 MOD 284318-01 | Bently Nevada

Technical Specifications

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). 

Functional Advantages

Two-wire circuit, no debugging required: Non-interactive zero and full-scale potentiometers are located below the housing label, allowing for direct fine-tuning within the circuit.

Circuit Self-Test (Test Input): Equipped with a test input pin, allowing maintenance personnel to quickly verify the correctness of signal readings from the back-end control system circuit by applying an external variable DC voltage source, without removing the sensor.

Test and Diagnostic Terminals

PROX OUT and COM: These provide raw eddy current signals in a non-isolated manner for long-term wiring to a local display meter or data acquisition unit.

TEST pin: Used to artificially simulate axial displacement by applying an external voltage without removing the sensor, thereby testing the alarm and trip logic of the back-end control system for proper functioning.

Technical FAQ

Q: What physical measurement range is specified by the "01" option in 991-01-XX-01-00 MOD 284318-01?

A: In the standard 991 configuration, the "01" option indicates that the transmitter is configured for a total axial displacement measurement range of 25-0-25 mils (a total travel of 50 mils, approximately 1.2 mm).

Q: How does the 4-20 mA loop current of 991-01-XX-01-00 MOD 284318-01 define axial direction?

A: The 4-20 mA output is linearly proportional to axial displacement. Typically, 12 mA represents the proximity probe's zero or balanced position. Current values below 12 mA indicate movement toward the probe (inboard direction), while values above 12 mA indicate movement away from the probe (outboard direction).

Q: How should the "XX" value be determined when ordering 991-01-XX-01-00 MOD 284318-01 based on the field hardware configuration?

A: "XX" represents the total nominal system length of the proximity probe plus the extension cable. If the total system length is 5.0 meters, select 50. If the total system length is 7.0 meters, select 70.

Q: What do the suffixes "00" and "01" specify in 991-01-XX-01-00 MOD 284318-01?

A: The second-to-last "01" indicates that the transmitter is supplied with standard 35 mm DIN rail clips for mounting. The final "00" designates the basic version intended for non-hazardous locations or general industrial electrical environments.

Q: Are your products brand new?
A: Yes. We only supply 100% original and brand-new products. All items are sourced through authorized channels and have never been used or refurbished.

Q: Why can customers buy with confidence?
A: Because every product is backed by our 1-Year Warranty Guarantee of Quality, ensuring reliability, customer satisfaction, and long-term support after delivery.

Q: Do you provide international shipping?
A: Yes. We ship products to customers worldwide using reliable international logistics services such as EMS, DHL, UPS, and FedEx.

Trusted by 5,000+ plants worldwide |  Contact for more Bently Nevada spares: sales1@amikon.cn

You May Also Like: