3500/50M-01-00 286566-02 Bently Nevada Tachometer Module

Introduction to the 3500/50M-01-00 286566-02 Tachometer Module

When rotating machinery demands precise speed measurement, the 3500/50M-01-00 286566-02 from Bently Nevada delivers reliable performance. This Tachometer Module is engineered for industrial monitoring systems, accepting up to two transducer signals from proximity probes or magnetic pickups. It provides accurate RPM readings and supports a wide range of full-scale values up to 99,999 rpm.

Manufactured in the U.S.A., this module is part of the 3500 monitoring system family. Its I/O module type is 01, indicating internal terminations, and the agency approval option is 00, meaning none. This configuration suits standard industrial applications where no special agency approvals are required.

Key Features and Technical Specifications

The 3500/50M-01-00 286566-02 offers a robust set of features for speed monitoring. Its input signal range spans +10.0 V to -24.0 V, with internal limiting for signals beyond this range. Input impedance is 20 kΩ standard, 40 kΩ with TMR, and 7.15 kΩ with internal barrier.

• Accepts 1 to 2 proximity transducer signals
• Power consumption: 5.8 Watts typical
• Buffered transducer outputs with 550 Ω output impedance
• Transducer power supply: 24 Vdc, 40 mA maximum per channel
• Recorder output: +4 to +20 mA proportional to full-scale range
• Resolution: 0.3662 µA per bit ±0.25% error at room temperature
• Update rate: approximately 100 ms

These specifications ensure accurate and stable speed measurement, critical for protecting rotating equipment. The module's high input impedance minimizes loading on transducers, while the buffered outputs allow safe signal distribution.

Performance and Accuracy

The 3500/50M-01-00 286566-02 provides excellent RPM accuracy across its range. For speeds less than 100 rpm, accuracy is ±0.1 rpm. Between 100 and 10,000 rpm, accuracy is ±1 rpm. Above 10,000 rpm, accuracy is ±0.01% of true shaft speed. RPM/Min accuracy is ±20 rpm/min.

Signal conditioning includes auto threshold for inputs above 0.0167 Hz, with a minimum trigger amplitude of 1 volt peak-to-peak. Manual threshold is user-selectable from +9.5 Vdc to -23.5 Vdc, with a minimum trigger amplitude of 500 millivolts peak-to-peak. Hysteresis is adjustable from 0.2 to 2.5 volts.

These features allow the module to handle various transducer types and signal conditions, ensuring reliable operation in demanding environments.

Applications and Use Cases

The 3500/50M-01-00 286566-02 is ideal for turbine, compressor, and pump monitoring. It supports up to 255 events per revolution for Rotor Acceleration and Zero Speed channel types, making it suitable for critical machinery protection. Other channel types support 0.0039 to 255 events per revolution, with a maximum input frequency of 20 kHz.

In real-world scenarios, this module helps detect speed anomalies early, preventing costly downtime. For example, in a steam turbine, accurate speed measurement is vital for overspeed protection. The module's high accuracy and fast update rate enable timely response to speed changes.

Installation and Setup

Installing the 3500/50M-01-00 286566-02 requires a full-height front slot in a 3500 rack. The module dimensions are 241.3 mm x 24.4 mm x 241.8 mm (9.50 in x 0.96 in x 9.52 in) and it weighs 0.82 kg (1.8 lb). Ensure proper grounding and shielding of transducer cables to maintain signal integrity.

Before installation, verify firmware compatibility. The 3500/50M requires firmware revision 5.30 or later. The 3500/22M module must have firmware revision 1.70, and configuration software must be version 4.20 or later. Data acquisition software should be version 2.52 or later, and display software version 1.52 or later. Note that the 3500/50M is not compatible with any version of the 3500/20.

Maintenance and Reliability

Regular inspection of the 3500/50M-01-00 286566-02 ensures long-term reliability. Check front panel LEDs for proper operation: OK LED indicates normal operation, TX/RX LED shows communication, and Bypass LED indicates bypass mode. Verify that all connections are secure and free from corrosion.

Environmental factors such as temperature and humidity can affect performance. Operate the module within specified conditions, and keep the rack area clean and well-ventilated. Periodic testing of alarm setpoints and recorder outputs helps maintain system integrity.

Compatibility and Integration

The 3500/50M-01-00 286566-02 integrates seamlessly into the 3500 monitoring system. It communicates with other modules via the rack backplane, as indicated by the TX/RX LED. The module supports up to two channels, each with buffered transducer outputs available at the I/O module via Euro style connectors.

For system integration, ensure that the 3500/01 Configuration Software version 4.20 or later is used. The 3500/02 Data Acquisition Software version 2.52 or later and 3500/03 Display Software version 1.52 or later are also required. These software versions ensure full functionality and data acquisition capabilities.

Buyer's Guide: Evaluating the 3500/50M-01-00 286566-02

When considering the 3500/50M-01-00 286566-02 for your application, evaluate your specific requirements. Key factors include the number of channels needed, input signal types, and required accuracy. The module accepts up to two transducer signals, making it suitable for single or dual-probe setups.

Check the input signal range (+10.0 V to -24.0 V) against your transducer output. Ensure that the input impedance matches your transducer specifications. For magnetic pickups, verify that the minimum input frequency of 3.3 Hz is acceptable for your speed range.

Consider the recorder outputs (+4 to +20 mA) for integration with your data acquisition system. The output is proportional to the full-scale range, and individual values are provided for each channel. Short circuits on recorder outputs do not affect monitor operation, adding robustness.

Product Support and Availability

The 3500/50M-01-00 286566-02 is available from AutoDCSTech, an industrial automation parts supplier. Please verify current lifecycle status and availability with AutoDCSTech before ordering. Our team can assist with compatibility and technical questions.