Bently Nevada 991-06-70-01-00 Thrust Transmitter for Axial Position Monitoring

This Bently Nevada thrust transmitter provides continuous axial position monitoring for rotating machinery shafts. It converts proximity probe signals into a standard 4-20 mA output for control systems. Engineers can deploy this unit for turbines, compressors, and large motor thrust bearing protection. Its two-wire loop-powered design simplifies installation and reduces wiring complexity significantly. The transmitter integrates seamlessly with PLC, DCS, and SCADA control systems.

Physical Dimensions and Housing Design

The transmitter measures 4.0 inches in height and 2.5 inches in width. Its rugged aluminum housing weighs approximately 1.2 pounds for durable panel mounting. A DIN-rail mounting clip secures the unit inside control cabinets conveniently. The housing includes a removable terminal cover for wiring access and protection. This design simplifies installation and maintenance procedures in the field.

Input Signal Compatibility and Sensor Interfaces

The transmitter accepts inputs from Bently Nevada 3300 XL proximity probes and other eddy current sensors. It supports both 5 mm and 8 mm probe systems for versatile connectivity. The unit provides a -24 VDC excitation output for powering the proximity probe driver. This flexibility accommodates various sensor configurations without additional hardware. The transmitter also handles signal ranges up to 10 V peak.

Output Signal and Loop Characteristics

The unit provides a standard 4-20 mA output proportional to thrust position. This output loops directly into existing process control systems without modification. The transmitter operates on a loop supply voltage from 12 to 30 VDC. It features a maximum loop resistance of 600 ohms for reliable signal transmission. The output scales to full-scale ranges from 0-10 mils to 0-100 mils.

Configuration and Adjustment Features

The transmitter includes potentiometers for zero and span adjustments on the front panel. Users can configure the full-scale range using simple DIP switch settings. The unit also provides a test input for verifying system calibration and operation. This feature simplifies commissioning and routine maintenance checks. The transmitter stores configuration parameters in non-volatile memory for power-loss retention.

Diagnostic and Status Indication

The front panel features two LED indicators for power and fault status. The transmitter performs continuous self-diagnostics on its internal circuitry. It detects sensor open-circuit and short-circuit conditions automatically. The unit reports faults by driving the output below 3.6 mA or above 21 mA. This diagnostic capability ensures reliable machine protection and alarm functionality.

Environmental Ratings and Compliance Standards

The transmitter operates reliably from -40 to 85 degrees Celsius ambient temperature. Its conformal-coated PCB resists moisture and airborne contaminants effectively. The unit withstands 95% non-condensing humidity for versatile industrial deployment. It carries CE and ATEX certifications for use in hazardous area applications. This compliance simplifies equipment certification for international projects.

Technical Specifications Overview