The 3500/50-01-00 functions as a highly accurate dual-channel speed monitoring and processing component designed for integration within the Bently Nevada 3500 Series Machinery Protection System rack architecture. This high-performance tachometer processor receives dynamic input signals from industrial proximity probes or passive magnetic pickups to compute essential rotational diagnostics. It continuously tracks critical parameters such as shaft rotative speed, rotor acceleration rates, and directional rotation vectors. The 3500/50M processor then compares these real-time physical variables against user-programmed alarm configurations to prompt immediate plant alert logic when monitored limits are crossed.
Engineered with specialized firmware, the 3500/50-01-00 module type can be configured to supply conditioned Keyphasor signals directly to the 3500 backplane, eliminating the spatial requirement for a dedicated standalone Keyphasor module inside the micro-processor rack. For secondary logging and data visualization, each processing channel provides isolated +4 to +20 mA analog recorder proportional voltage outputs alongside continuous short-circuit protected buffered transducer connections via front panel coaxial interfaces. This specific configuration incorporates an I/O module with internal terminations and contains no hazardous area approval options, delivering a dependable non-barrier interface solution for standard machinery machinery rooms.
Features
Dual-channel speed monitoring module accepting direct inputs from standard proximity sensors and magnetic pickups.
Provides onboard speed monitoring, setpoint alarming, speed band limits, and zero-speed notification metrics.
Configurable internal backplane routing for providing conditioned Keyphasor signals to adjacent protection cards.
Integrated peak hold features capturing highest forward speed, reverse velocity, and cumulative reverse rotation events.
Proportional +4 to +20 mA current loops for external chart recording, telemetry, and distributed management networks.
Applications
High-speed industrial centrifugal air compressors and process gas compressor balancing monitoring networks.
Rotor acceleration analysis and phase reference logging on steam, gas, and hydro power generation turbines.
Multi-channel reverse rotation indication and zero-speed safety validation across fluid-filmed bearing industrial machinery.
Ordering Information
Part Number
Option Breakdown and System Descriptions
3500/50-AA-BB
3500/50M Tachometer Module Assembly
A: 01
I/O Module with Internal Terminations
B: 00
Hazardous Area Approval Option: None
Technical Specifications
Parameter Classification
Precise Engineering Values
Manufacturer
Bently Nevada (Baker Hughes)
Main Part Number
3500/50-01-00
Module Variant
3500/50M Tachometer Module
Input Signal Range
+10.0 V to -24.0 V
Standard Input Impedance
20 kOhm
Typical Power Consumption
5.8 Watts
Maximum Input Frequency
20 kHz
Maximum Full Scale Range
99,999 rpm
RPM Accuracy (Under 100 rpm)
+/- 0.1 rpm
RPM Accuracy (100 to 10,000 rpm)
+/- 1 rpm
RPM Accuracy (Over 10,000 rpm)
+/- 0.01% of true shaft speed
Rotor Acceleration Accuracy
+/- 20 rpm/min
Recorder Current Output
+4 to +20 mA
Recorder Load Resistance Range
0 to 600 Ohm
Buffered Output Impedance
550 Ohm
Transducer Power Supply Limit
24 Vdc, 40 mA maximum per channel
Alarm 1 Delay Adjustments
1 to 60 seconds (1 second intervals)
Alarm 2 Delay Adjustments
1 to 60 seconds (0.1 second intervals)
Main Board Dimensions (H x W x D)
241.3 mm x 24.4 mm x 241.8 mm (9.50 in x 0.96 in x 9.52 in)
Main Board Net Weight
0.82 kg (1.8 lb)
I/O Module Dimensions (H x W x D)
241.3 mm x 24.4 mm x 99.1 mm (9.50 in x 0.96 in x 3.90 in)
I/O Module Net Weight
0.20 kg (0.44 lb)
Rack Space Requirement (Main)
1 full-height front rack slot
Rack Space Requirement (I/O)
1 full-height rear rack slot
Connections/Interfaces
Interface Component
Terminal Layout and Function Assignment
Front Panel Coaxial Port 1
Channel 1 buffered transducer voltage raw waveform diagnostic output
Front Panel Coaxial Port 2
Channel 2 buffered transducer voltage raw waveform diagnostic output
Internal Rear I/O Blocks
Dedicated terminal compression screws for transducer power, signals, shields, and recorder lines
Installation Guidelines
Rack Mounting Slot Rules: Insert the main tachometer processing board into any standard full-height front slot of the 3500 chassis and line up the internal termination rear I/O card directly behind it in the corresponding full-height rear slot.
Termination Cable Layout: Ensure all input cables from proximity or magnetic pickups are stripped to recommended lengths before locking down screw terminations. Maintain structural isolation between power-carrying conduits and signal loops to limit high-frequency electromagnetic interference.
Firmware and Software Compatibility Checks: Before introducing this module to an operating infrastructure, verify the rack's 3500/22M module firmware is upgraded to revision 1.70 or greater, and ensure the 3500/01 configuration utility runs version 4.20 or newer.
Electrostatic Grounding Measures: Personnel must wear a certified conductive grounding wrist strap attached to the chassis grounding terminal point when handling electronic circuit cards or moving jumpers to prevent physical component breakdown.
FAQ
Can passive magnetic pickups be used safely with the zero speed or reverse rotation options?
No. Passive magnetic pickups must not be used for reverse rotation or zero speed notification configurations because they do not provide a sufficiently sharp voltage edge for the detection circuitry during low speed states.
What is the maximum signal input frequency limits for the processing channels on this card?
The module channels support a maximum input frequency of 20 kHz and a maximum full-scale speed calculation value of 99,999 rpm.
Are the buffered output ports protected against short circuits or grounding faults?
Yes. Each coaxial buffered transducer output terminal on the front plate is fully short-circuit and electrostatic discharge protected without disrupting internal monitor functions.
What software version is needed to fully program the threshold options on this tachometer?
The system parameters must be programmed using the 3500 Rack Configuration software version 4.20 or later.
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