Bently Nevada 3500/50M-01-01 Tachometer Module

Bently Nevada 3500/50M-01-01 Tachometer Module for Speed Monitoring

Product Introduction

The 3500/50M-01-01 from Bently Nevada provides accurate speed measurement for rotating machinery. This tachometer module accepts up to two transducer signals per module. It works with proximity probe transducers or magnetic pickups.

You can use this module for multiple speed monitoring applications. These include shaft speed, rotor acceleration, and zero speed detection. The 3500/50M supports 1 to 255 events per revolution for rotor acceleration channels. For other channel types, it supports 0.0039 to 255 events per revolution.

Additionally, this version includes agency approval option 01. This provides cNRTLus certification for Class 1, Division 2 hazardous locations. The I/O module comes with internal terminations for easy wiring.

Firmware and Software Compatibility Requirements

Before adding the 3500/50M-01-01 to an existing 3500 system, check your firmware and software versions. The 3500/22M module requires firmware revision 1.70 or later.

Configuration Software must be version 4.20 or later. Data Acquisition Software needs version 2.52 or later. Display Software requires version 1.52 or later. The 3500/50M itself needs firmware revision 5.30 or later.

Please note that the 3500/50M is not compatible with any version of the 3500/20 rack interface module. Plan your system upgrade accordingly.

Input Signal Specifications

The 3500/50M-01-01 accepts input signals from +10.0 V to -24.0 V. The module internally limits signals that exceed this range. Input impedance varies based on your configuration.

Standard configuration uses 20 kΩ. TMR (Triple Modular Redundant) configuration uses 40 kΩ. The internal barrier option uses 7.15 kΩ. Power consumption runs at 5.8 watts typical.

The module provides a transducer power supply of 24 Vdc at 40 mA maximum per channel. This powers your proximity probes directly from the module.

Speed Measurement Capabilities

All channel types on the 3500/50M support a maximum full scale range of 99,999 rpm. The maximum input frequency reaches 20 kHz. For proximity transducers, the minimum input frequency is 0.0167 Hz. This equals 1 rpm for 1 event per revolution.

For passive magnetic pickups, the minimum input frequency is 3.3 Hz. This is an important consideration when choosing your transducer type.

RPM accuracy is excellent across the entire range. Below 100 rpm, accuracy stays at ±0.1 rpm. Between 100 and 10,000 rpm, accuracy reaches ±1 rpm. Above 10,000 rpm up to 99,999 rpm, accuracy is ±0.01% of true shaft speed. RPM/min accuracy is ±20 rpm/min.

Front Panel Indicators

The front panel includes several LEDs for status indication. The OK LED shows when the 3500/50M module operates correctly. The TX/RX LED indicates communication with other modules in the 3500 rack.

Furthermore, the Bypass LED lights up when the tachometer module is in Bypass Mode. These indicators help you quickly diagnose module status without opening the rack.

Physical Specifications and Rack Space

The monitor module (main board) measures 241.3 mm x 24.4 mm x 241.8 mm. It weighs 0.82 kg. This module occupies one full-height front slot in the 3500 rack.

The I/O module for 3500/50M-01-01 includes internal terminations and barrier. Its dimensions are 241.3 mm x 24.4 mm x 163.1 mm. Weight is 0.46 kg. This I/O module occupies one full-height rear slot.

For comparison, non-barrier I/O modules are smaller at 99.1 mm depth and weigh only 0.20 kg. Choose the correct I/O type based on your hazardous area requirements.

Installation Guidelines

First, verify that your 3500 system meets the firmware and software requirements. Power down the rack before inserting the 3500/50M-01-01 monitor module. Next, install the monitor module in a full-height front slot.

Then, install the I/O module in the corresponding rear slot. Connect your proximity probe or magnetic pickup transducers to the internal termination block. Secure all wiring according to the installation manual.

Finally, power up the system and configure the channel types using the 3500 Configuration Software version 4.20 or later. Set the events per revolution and full scale range for each channel.

Packaging List

• 1 x 3500/50M-01-01 Monitor Module (Tachometer main board)

• 1 x I/O module with internal terminations and barrier

• 1 x Internal termination block for transducer connections

• 2 x Channel configuration labels

• 1 x Quick start guide

Shipping via Fedex, UPS, or DHL

Frequently Asked Questions (FAQ)

1. Can the 3500/50M-01-01 work with my existing 3500/20 rack?
No, the 3500/50M is not compatible with any version of the 3500/20 rack interface module. You need a 3500/22M module with firmware revision 1.70 or later.

2. What is the minimum input frequency for magnetic pickups?
For passive magnetic pickups, the minimum input frequency is 3.3 Hz. For proximity transducers, the minimum is much lower at 0.0167 Hz.

3. How many events per revolution does the 3500/50M support?
For rotor acceleration and zero speed channel types, it supports 1 to 255 events per revolution. All other channel types support 0.0039 to 255 events per revolution.

4. What is the maximum speed I can measure with this module?
The 3500/50M-01-01 supports a maximum full scale range of 99,999 rpm for all channel types. The maximum input frequency is 20 kHz.

5. Does the cNRTLus approval cover Class 1, Division 2 groups?
Yes, agency approval option 01 provides cNRTLus certification for Class 1, Division 2 hazardous locations. Always verify your specific area classification before installation.