Online Vibration Monitor
medium
8 models total
An online vibration monitor differs from a portable data collector in one respect that matters more than any spec sheet: it never stops watching, which is the only way to catch a bearing that degrades over hours rather than weeks between rounds.
Read more — Online Vibration Monitor explained ▾
What this type is
An online vibration monitoring system permanently mounts accelerometers or velocity sensors on critical machinery — main engine, propulsion shafting, turbochargers, large pumps and compressors — and feeds their signal continuously to a monitoring unit rather than relying on a technician walking round with a portable collector. The difference from portable monitoring is not accuracy but coverage in time: a permanent system catches a fast-developing fault, such as a turbocharger bearing failing over a few hours, that a monthly or quarterly round would only find after the fact.
Main components
- Sensors — accelerometers for high-frequency bearing and gear defects, velocity transducers for lower-frequency unbalance and misalignment, sometimes proximity probes for shaft displacement on fluid-film bearings.
- Signal conditioning / data acquisition unit — converts raw sensor signal into usable spectra and trend values, often mounted local to the machine.
- Monitoring processor — runs the alarm logic, stores trend history, and in many installations feeds the vessel's alarm and monitoring system directly.
- Software/HMI — displays spectra, waterfall plots and trend charts, and lets an engineer set alarm thresholds per machine and per measurement point.
Selection and sizing
Sizing is driven by how many measurement points the machinery needs, not by a single monitor size. A main engine may need points on each main bearing and the turbocharger; a shaft line needs axial and radial coverage at the thrust and line bearings. Sensor frequency range must match the fault types expected — gear mesh and bearing defects generate high-frequency content that a low-bandwidth sensor will miss entirely.
| Machine | Typical points | Primary concern |
|---|---|---|
| Main engine bearings | 1 per bearing | Unbalance, misalignment, bearing wear |
| Turbocharger | 1-2 radial | Bearing degradation, blade fouling |
| Shaft line | Thrust + line bearings | Axial movement, alignment drift |
Regulations and class
Class societies offer machinery condition monitoring notations (schemes vary by society) that permit extended survey intervals on machinery covered by an approved online monitoring system, in place of some fixed-interval opening-up inspections. Qualifying for the notation requires the monitoring scope, alarm limits and data retention to meet the society's rules, and the system's calibration record is checked at survey.
Typical faults
- Sensor cable damaged by heat or chafe near the engine, producing a flat-lined or noisy signal that is mistaken for a healthy machine.
- Alarm thresholds left at factory default rather than set for the specific machine's baseline, causing either nuisance alarms or missed trends.
- Sensor mounting loosened by vibration over time, shifting the measured frequency response and invalidating trend comparisons.
- Software left unmonitored — the system logs data correctly but no one reviews the trend until an alarm finally trips.
What to look for in a supplier
- Sensor frequency range matched to the specific fault types on the machinery in question, not a generic industrial sensor.
- Compatibility with the vessel's existing alarm and monitoring system, or a clear standalone alternative.
- Support for the class society's condition monitoring notation if that is the vessel's goal.
- Local technical support able to help set realistic alarm baselines, not just supply hardware.
A trend line is only as good as its baseline — record a full spectrum on newly installed or overhauled machinery while it is known to be healthy, or every later alarm threshold is a guess.
4 manufacturers · 8 models
SKF Marine
4
Multilog IMx-16/32
16-32 channels
· Vibration Monitoring
· online vibration monitoring system
Type
Online Vibration Monitor
Common Failures & Inspection Points
- Corrosion, wastage or coating breakdown causes visible section loss and weakens the fitting or surrounding structure
- Wear in pins, rollers, hinges or bearing surfaces causes excessive play, stiffness or poor line guidance
- Seal or gasket deterioration on closing appliances causes water ingress or loss of weathertight integrity
- Loose foundations, fasteners or cracked welds cause movement, vibration or visible structural defects
- Blocked drains, vents or passages cause water accumulation, pressure problems or restricted operation
Service: Inspect structural attachment, corrosion, welds, fasteners, moving parts, seals and coatings. Verify free movement, drainage, closing and securing functions according to the fitting type. Pay particular attention to load-bearing foundations and watertight or weathertight boundaries. Refer to class, vessel and manufacturer documentation for the exact figure for loads, clearances and acceptance limits.
Spare Parts: Carry seals or gaskets, pins, bushes, rollers, approved fasteners, lubrication items and small operating hardware appropriate to the installed fitting.
Strengths
- Real‑time multi‑channel monitoring (16 or 32 accelerometers) with built‑in alarm thresholds
- Modular hardware allows easy expansion and integration with existing shipboard SCADA/CMMS
- Robust marine‑grade enclosure and IP66 protection for harsh environments
- Remote diagnostics and data logging enable trend analysis without manual trips to the engine room
- Standardized SKF accelerometers simplify calibration and spare‑part management
Weaknesses
- Higher upfront capital cost compared with basic handheld vibration meters
- Annual calibrations are required to maintain accuracy, adding maintenance workload
- Accelerometer cable damage is a common failure mode in high‑vibration zones
- Installation requires careful sensor mounting and routing of cables, increasing installation time
- Limited frequency range (up to ~10 kHz) may not capture very high‑frequency events
Typical Vessels:
TankerContainer shipBulk carrierOffshore support vesselCruise ship
Decision Guide: Choose if: you need continuous, real‑time vibration data for critical engines, gearboxes or shafts and have the capability to perform regular calibrations; you want predictive maintenance integration with minimal manual sampling. Avoid if: budget constraints prohibit a multi‑channel online system, you only require occasional spot checks, or space/installation constraints make extensive cabling impractical.
Use Cases: Mooring, deck access, cargo access, drainage, ventilation and general deck service.
SKF Multilog IMx-8
unverified
· online 8-channel vibration monitor
Monitor type
online
Description
online 8-channel vibration monitor
Application
marine machinery condition monitoring
Common Failures & Inspection Points
- Sensor detachment or poor mounting can distort readings, seen as sudden signal changes unrelated to machinery condition
- Cable or connector damage can cause intermittent or lost channels
- Calibration drift can bias measurements and trend interpretation
- Power or data-acquisition faults can stop recording or produce invalid channels
- Incorrect measurement location or configuration can make trends inconsistent and difficult to compare
Service: Inspect sensor mounting, cable routing, connectors and data quality and compare trends at consistent operating conditions. Verify calibration status and investigate step changes before relying on alarm thresholds. Exact alert and danger limits must be based on the machinery, class and manufacturer documentation rather than assumed values.
Spare Parts: Carry compatible sensors, magnetic or stud mounting accessories as applicable, cables, connectors, batteries and maker-recommended acquisition-module parts.
Use Cases: Used on propulsion, generators, pumps, fans, compressors and other rotating machinery for condition-based maintenance and fault diagnosis.
SKF Multilog IMx-16
unverified
· online 16-channel vibration monitor
Monitor type
online
Description
online 16-channel vibration monitor
Application
marine machinery condition monitoring
Common Failures & Inspection Points
- Sensor detachment or poor mounting can distort readings, seen as sudden signal changes unrelated to machinery condition
- Cable or connector damage can cause intermittent or lost channels
- Calibration drift can bias measurements and trend interpretation
- Power or data-acquisition faults can stop recording or produce invalid channels
- Incorrect measurement location or configuration can make trends inconsistent and difficult to compare
Service: Inspect sensor mounting, cable routing, connectors and data quality and compare trends at consistent operating conditions. Verify calibration status and investigate step changes before relying on alarm thresholds. Exact alert and danger limits must be based on the machinery, class and manufacturer documentation rather than assumed values.
Spare Parts: Carry compatible sensors, magnetic or stud mounting accessories as applicable, cables, connectors, batteries and maker-recommended acquisition-module parts.
Use Cases: Used on propulsion, generators, pumps, fans, compressors and other rotating machinery for condition-based maintenance and fault diagnosis.
SKF Multilog IMx-32
unverified
· online 32-channel vibration monitor
Monitor type
online
Description
online 32-channel vibration monitor
Application
marine machinery condition monitoring
Common Failures & Inspection Points
- Sensor detachment or poor mounting can distort readings, seen as sudden signal changes unrelated to machinery condition
- Cable or connector damage can cause intermittent or lost channels
- Calibration drift can bias measurements and trend interpretation
- Power or data-acquisition faults can stop recording or produce invalid channels
- Incorrect measurement location or configuration can make trends inconsistent and difficult to compare
Service: Inspect sensor mounting, cable routing, connectors and data quality and compare trends at consistent operating conditions. Verify calibration status and investigate step changes before relying on alarm thresholds. Exact alert and danger limits must be based on the machinery, class and manufacturer documentation rather than assumed values.
Spare Parts: Carry compatible sensors, magnetic or stud mounting accessories as applicable, cables, connectors, batteries and maker-recommended acquisition-module parts.
Use Cases: Used on propulsion, generators, pumps, fans, compressors and other rotating machinery for condition-based maintenance and fault diagnosis.
Bruel & Kjaer
2
Brüel & Kjær VIBIO M
unverified
· online vibration monitor (marine)
Monitor type
online
Description
online vibration monitor (marine)
Application
marine vibration analysis
Common Failures & Inspection Points
- Sensor detachment or poor mounting can distort readings, seen as sudden signal changes unrelated to machinery condition
- Cable or connector damage can cause intermittent or lost channels
- Calibration drift can bias measurements and trend interpretation
- Power or data-acquisition faults can stop recording or produce invalid channels
- Incorrect measurement location or configuration can make trends inconsistent and difficult to compare
Service: Inspect sensor mounting, cable routing, connectors and data quality and compare trends at consistent operating conditions. Verify calibration status and investigate step changes before relying on alarm thresholds. Exact alert and danger limits must be based on the machinery, class and manufacturer documentation rather than assumed values.
Spare Parts: Carry compatible sensors, magnetic or stud mounting accessories as applicable, cables, connectors, batteries and maker-recommended acquisition-module parts.
Use Cases: Used on propulsion, generators, pumps, fans, compressors and other rotating machinery for condition-based maintenance and fault diagnosis.
Brüel & Kjær VIBIO M-16
unverified
· online 16-channel vibration monitor (marine)
Monitor type
online
Description
online 16-channel vibration monitor (marine)
Application
marine vibration analysis
Common Failures & Inspection Points
- Sensor detachment or poor mounting can distort readings, seen as sudden signal changes unrelated to machinery condition
- Cable or connector damage can cause intermittent or lost channels
- Calibration drift can bias measurements and trend interpretation
- Power or data-acquisition faults can stop recording or produce invalid channels
- Incorrect measurement location or configuration can make trends inconsistent and difficult to compare
Service: Inspect sensor mounting, cable routing, connectors and data quality and compare trends at consistent operating conditions. Verify calibration status and investigate step changes before relying on alarm thresholds. Exact alert and danger limits must be based on the machinery, class and manufacturer documentation rather than assumed values.
Spare Parts: Carry compatible sensors, magnetic or stud mounting accessories as applicable, cables, connectors, batteries and maker-recommended acquisition-module parts.
Use Cases: Used on propulsion, generators, pumps, fans, compressors and other rotating machinery for condition-based maintenance and fault diagnosis.
Bently Nevada (Baker Hughes)
1
3500 Series
Per machine, 4-24 channels
· Vibration Monitoring
· Online vibration monitoring
Type
Machinery Protection System
Common Failures & Inspection Points
- Corrosion, wastage or coating breakdown causes visible section loss and weakens the fitting or surrounding structure
- Wear in pins, rollers, hinges or bearing surfaces causes excessive play, stiffness or poor line guidance
- Seal or gasket deterioration on closing appliances causes water ingress or loss of weathertight integrity
- Loose foundations, fasteners or cracked welds cause movement, vibration or visible structural defects
- Blocked drains, vents or passages cause water accumulation, pressure problems or restricted operation
Service: Inspect structural attachment, corrosion, welds, fasteners, moving parts, seals and coatings. Verify free movement, drainage, closing and securing functions according to the fitting type. Pay particular attention to load-bearing foundations and watertight or weathertight boundaries. Refer to class, vessel and manufacturer documentation for the exact figure for loads, clearances and acceptance limits.
Spare Parts: Carry seals or gaskets, pins, bushes, rollers, approved fasteners, lubrication items and small operating hardware appropriate to the installed fitting.
Strengths
- Proven reliability with decades of field service in marine environments
- Modular I/O architecture allows spare Proximitor, Keyphasor, and relay modules to be stocked for quick replacement
- Integrated proximity probe driver (Proximitor) and phase detection (Keyphasor) provide comprehensive bearing and shaft monitoring
- Immediate alarm and relay outputs enable automatic shutdown of equipment on fault detection
- Widely accepted by classification societies and compatible with existing Bently Nevada infrastructure
Weaknesses
- Documented failure modes include Proximitor driver, Keyphasor signal loss, relay module faults, and rack power‑supply failures
- Higher capital cost compared with some newer cloud‑based condition monitoring platforms
- Limited built‑in remote analytics; requires external software for advanced trend analysis
- Annual sensor calibration is mandatory to maintain accuracy
- Physical rack size can be bulky for vessels with limited equipment space
Typical Vessels:
TankerContainer ShipBulk CarrierCruise ShipOffshore Support VesselLNG Carrier
Certifications:
IMO D-2
Decision Guide: Choose if: you need a battle‑tested, class‑approved vibration protection system with modular spare parts and direct integration to existing Bently Nevada hardware. Avoid if: budget constraints favor lower‑cost solutions or you require advanced cloud analytics and compact form factor that newer IoT condition monitoring units provide.
Use Cases: Mooring, deck access, cargo access, drainage, ventilation and general deck service.
Brüel & Kjær (HBK)
1
VIBROCONTROL 6000
Up to 128 channels
· Vibration Monitoring
· online vibration monitoring system
Type
Vibration Protection System
Common Failures & Inspection Points
- Corrosion, wastage or coating breakdown causes visible section loss and weakens the fitting or surrounding structure
- Wear in pins, rollers, hinges or bearing surfaces causes excessive play, stiffness or poor line guidance
- Seal or gasket deterioration on closing appliances causes water ingress or loss of weathertight integrity
- Loose foundations, fasteners or cracked welds cause movement, vibration or visible structural defects
- Blocked drains, vents or passages cause water accumulation, pressure problems or restricted operation
Service: Inspect structural attachment, corrosion, welds, fasteners, moving parts, seals and coatings. Verify free movement, drainage, closing and securing functions according to the fitting type. Pay particular attention to load-bearing foundations and watertight or weathertight boundaries. Refer to class, vessel and manufacturer documentation for the exact figure for loads, clearances and acceptance limits.
Spare Parts: Carry seals or gaskets, pins, bushes, rollers, approved fasteners, lubrication items and small operating hardware appropriate to the installed fitting.
Strengths
- API 670 and ISO 10816 compliant – meets marine condition‑monitoring standards
- Multi‑channel architecture allows simultaneous monitoring of several shafts or bearings
- Integrated relay outputs enable automatic shutdown or alarm to plant control systems
- Built‑in trend analysis and data logging support predictive maintenance programmes
- Modular hardware can be expanded with additional probe types (accelerometers, pressure sensors)
Weaknesses
- Requires annual calibration of proximity probes to maintain accuracy
- Known field failures include probe gap drift, relay output faults and channel‑card malfunctions
- Higher upfront cost compared with simple handheld vibration meters
- Installation and configuration demand trained engineering personnel
- Power‑supply sensitivity – must be protected against shipboard voltage transients
Typical Vessels:
TankerContainer shipBulk carrierOffshore support vesselCruise linerLNG/LPG carrier
Decision Guide: Choose if: you need continuous, API‑670 compliant shaft vibration monitoring with automatic alarm/relay integration for predictive maintenance. Avoid if: budget constraints preclude a modular online system or the crew lacks capability to perform regular probe calibration and fault diagnostics.
Use Cases: Mooring, deck access, cargo access, drainage, ventilation and general deck service.