Speed Log
A speed log measures the ship's actual speed through the water, which is not the same figure a GPS reports as speed over ground, and it is what feeds squat and manoeuvring calculations that current alone cannot supply.
Read more — Speed Log explained ▾
What sets the speed log apart
A speed log measures the ship's own speed, either through the surrounding water or over the seabed, and feeds that figure to ECDIS, radar vector calculations, the autopilot and engine performance monitoring. It is not interchangeable with GPS-derived speed over ground: GPS tells the ship how fast it is covering distance across the earth, including the effect of current, while a true speed log measures motion relative to the water itself, which is what manoeuvring, squat and set-and-drift calculations actually need.
Main components and types
Electromagnetic log
A sensor probe protrudes slightly through the hull and measures the small voltage induced as water flows past it, giving speed through water on the fore-aft axis and, on dual-axis units, athwartship speed as well, which matters during berthing on larger ships.
Doppler log
An acoustic transducer sends a signal toward the seabed and measures the frequency shift of the return, giving speed over ground while the seabed is within range, typically up to a few hundred metres of water depth; beyond that range it reverts to measuring against a water layer instead, giving speed through water without always making the switch obvious to the user.
Sensor housing
Many logs use a retractable housing so the sensor can be withdrawn for cleaning or inspection without dry-docking the ship, sealed by a valve when retracted.
Selection and sizing
- Single-axis logs cover fore-aft speed only; dual-axis logs add transverse speed, useful for ships that need close manoeuvring data during berthing.
- Doppler bottom-tracking range against the ship's typical operating depths, since deep-water passages rely on water-track mode instead.
- Retractable versus fixed sensor housing, weighed against maintenance access and the hull maintenance schedule.
Regulations and class
SOLAS Chapter V requires ships above a certain size on international voyages to carry a speed and distance measuring device, and IMO performance standards set accuracy requirements for it. Class surveys check the transducer seacock or valve for watertight integrity, since it is a hull penetration below the waterline.
Typical faults
| Fault | Cause | Consequence |
|---|---|---|
| Sensor fouling | Marine growth on the electromagnetic sensor face | Reading drifts and typically underreads actual speed |
| Bottom-lock loss | Doppler log operating in water too deep for seabed return | Silent switch to water-track mode, speed over ground accuracy lost without a clear warning |
| Retraction mechanism seizure | Corrosion or lack of exercise of the housing | Sensor cannot be withdrawn for maintenance, forcing a dry-dock delay |
| Calibration bias | Hull cleaning or repainting changing flow characteristics at the sensor | Systematic speed error across the whole operating range |
What to look for in a supplier
- Transducer material and coating compatible with the ship's hull coating regime.
- Reliability record of the retractable housing mechanism.
- Calibration support after installation, hull cleaning, or dry-docking.
- Standard data output, typically NMEA, compatible with the existing bridge systems.
GPS speed over ground looking correct on the display is not proof the log is working — through-water speed is what manoeuvring and squat calculations actually rely on, and only the log measures it independently of current.
8 manufacturers · 58 models
Furuno
11- Sensor or transmitter failure caused by electronics, RF, antenna or transducer faults, noticed as missing or degraded navigation data
- External sensor-input failure caused by GNSS, heading, speed or network faults, noticed as alarms, frozen data or misaligned overlays
- Display/processor failure caused by power, cooling, storage or software faults, noticed as blank screen, rebooting or unavailable functions
- Antenna/transducer/cable damage caused by weather, water ingress, fouling or impact, noticed as weak, intermittent or implausible signals
- Incorrect configuration or calibration caused by maintenance or operator error, noticed as persistent disagreement with independent references
- Sensor or transmitter failure caused by electronics, RF, antenna or transducer faults, noticed as missing or degraded navigation data
- External sensor-input failure caused by GNSS, heading, speed or network faults, noticed as alarms, frozen data or misaligned overlays
- Display/processor failure caused by power, cooling, storage or software faults, noticed as blank screen, rebooting or unavailable functions
- Antenna/transducer/cable damage caused by weather, water ingress, fouling or impact, noticed as weak, intermittent or implausible signals
- Incorrect configuration or calibration caused by maintenance or operator error, noticed as persistent disagreement with independent references
- Sensor or transmitter failure caused by electronics, RF, antenna or transducer faults, noticed as missing or degraded navigation data
- External sensor-input failure caused by GNSS, heading, speed or network faults, noticed as alarms, frozen data or misaligned overlays
- Display/processor failure caused by power, cooling, storage or software faults, noticed as blank screen, rebooting or unavailable functions
- Antenna/transducer/cable damage caused by weather, water ingress, fouling or impact, noticed as weak, intermittent or implausible signals
- Incorrect configuration or calibration caused by maintenance or operator error, noticed as persistent disagreement with independent references
- Loss of sensor input or damaged cabling causes missing, frozen or implausible navigation data
- Antenna, transducer or scanner faults reduce detection or measurement performance and generate equipment alarms
- Power-supply or cooling faults cause resets, blank displays or complete loss of function
- Configuration or interface faults cause disagreement between systems or missing data on connected equipment
- Display, control or processing faults cause unstable operation, error messages or inability to select required functions
- Loss of sensor input or damaged cabling causes missing, frozen or implausible navigation data
- Antenna, transducer or scanner faults reduce detection or measurement performance and generate equipment alarms
- Power-supply or cooling faults cause resets, blank displays or complete loss of function
- Configuration or interface faults cause disagreement between systems or missing data on connected equipment
- Display, control or processing faults cause unstable operation, error messages or inability to select required functions
- Sensor, antenna or transducer fouling, damage or misalignment causes unstable, missing or inaccurate data
- Power-supply or processor faults cause resets, blank displays or complete loss of indication
- Cable, connector or network faults cause intermittent data or loss of outputs to other bridge systems
- Incorrect configuration or calibration causes persistent disagreement with independent references
- Display or software faults cause frozen values, alarms or unavailable functions
- Loss of electrical, hydraulic, pneumatic, or other service supply caused by a tripped protection device, leakage, blockage, or upstream fault results in failed starting or loss of function
- Mechanical wear, corrosion, fouling, or contamination of moving and wetted parts causes increased noise, leakage, sticking, vibration, or reduced performance
- Seal, gasket, hose, cable, or connection deterioration from age, heat, vibration, or environmental exposure produces visible leakage, intermittent signals, or loss of pressure
- Sensor, switch, actuator, relay, or control-system faults can cause incorrect indication, nuisance alarms, failed automatic sequences, or loss of remote control
- Incorrect adjustment, assembly, or maintenance can lead to unstable operation, recurrent alarms, or performance that differs from the vessel's normal baseline
- Loss of electrical, hydraulic, pneumatic, or other service supply caused by a tripped protection device, leakage, blockage, or upstream fault results in failed starting or loss of function
- Mechanical wear, corrosion, fouling, or contamination of moving and wetted parts causes increased noise, leakage, sticking, vibration, or reduced performance
- Seal, gasket, hose, cable, or connection deterioration from age, heat, vibration, or environmental exposure produces visible leakage, intermittent signals, or loss of pressure
- Sensor, switch, actuator, relay, or control-system faults can cause incorrect indication, nuisance alarms, failed automatic sequences, or loss of remote control
- Incorrect adjustment, assembly, or maintenance can lead to unstable operation, recurrent alarms, or performance that differs from the vessel's normal baseline
- Sensor fouling caused by marine growth, paint or debris, resulting in low or unstable speed indication
- Transducer or cabling fault caused by water ingress or electrical damage, resulting in loss of speed data
- Calibration drift caused by sensor aging or installation changes, resulting in persistent disagreement with expected speed
- Processor or display failure caused by power or electronics faults, resulting in blank or frozen indication
- Interface failure caused by network or serial-data faults, resulting in missing speed input at radar, ECDIS or other systems
- Sensor fouling caused by marine growth, paint or debris, resulting in low or unstable speed indication
- Transducer or cabling fault caused by water ingress or electrical damage, resulting in loss of speed data
- Calibration drift caused by sensor aging or installation changes, resulting in persistent disagreement with expected speed
- Processor or display failure caused by power or electronics faults, resulting in blank or frozen indication
- Interface failure caused by network or serial-data faults, resulting in missing speed input at radar, ECDIS or other systems
- Loss of electrical, hydraulic, pneumatic, or other service supply caused by a tripped protection device, leakage, blockage, or upstream fault results in failed starting or loss of function
- Mechanical wear, corrosion, fouling, or contamination of moving and wetted parts causes increased noise, leakage, sticking, vibration, or reduced performance
- Seal, gasket, hose, cable, or connection deterioration from age, heat, vibration, or environmental exposure produces visible leakage, intermittent signals, or loss of pressure
- Sensor, switch, actuator, relay, or control-system faults can cause incorrect indication, nuisance alarms, failed automatic sequences, or loss of remote control
- Incorrect adjustment, assembly, or maintenance can lead to unstable operation, recurrent alarms, or performance that differs from the vessel's normal baseline
Raytheon Anschütz
8
- Sensor or antenna degradation caused by contamination, damage, ageing or poor exposure can produce missing, unstable or implausible data
- Connector, cable or network faults caused by vibration, corrosion or disturbed terminations can cause intermittent data loss or interface alarms
- Power-supply or internal electronics failure caused by ageing, heat or poor ventilation can result in resets, blank indications or complete loss of function
- Configuration or software errors after service or replacement can cause incorrect data, rejected inputs or loss of communication with other bridge equipment
- Mechanical damage or water ingress at exposed components can lead to erratic readings, repeated alarms or loss of the affected channel
- Loss of electrical, hydraulic, pneumatic, or other service supply caused by a tripped protection device, leakage, blockage, or upstream fault results in failed starting or loss of function
- Mechanical wear, corrosion, fouling, or contamination of moving and wetted parts causes increased noise, leakage, sticking, vibration, or reduced performance
- Seal, gasket, hose, cable, or connection deterioration from age, heat, vibration, or environmental exposure produces visible leakage, intermittent signals, or loss of pressure
- Sensor, switch, actuator, relay, or control-system faults can cause incorrect indication, nuisance alarms, failed automatic sequences, or loss of remote control
- Incorrect adjustment, assembly, or maintenance can lead to unstable operation, recurrent alarms, or performance that differs from the vessel's normal baseline
- Sensor or antenna degradation caused by contamination, damage, ageing or poor exposure can produce missing, unstable or implausible data
- Connector, cable or network faults caused by vibration, corrosion or disturbed terminations can cause intermittent data loss or interface alarms
- Power-supply or internal electronics failure caused by ageing, heat or poor ventilation can result in resets, blank indications or complete loss of function
- Configuration or software errors after service or replacement can cause incorrect data, rejected inputs or loss of communication with other bridge equipment
- Mechanical damage or water ingress at exposed components can lead to erratic readings, repeated alarms or loss of the affected channel
- Sensor or antenna degradation caused by contamination, damage, ageing or poor exposure can produce missing, unstable or implausible data
- Connector, cable or network faults caused by vibration, corrosion or disturbed terminations can cause intermittent data loss or interface alarms
- Power-supply or internal electronics failure caused by ageing, heat or poor ventilation can result in resets, blank indications or complete loss of function
- Configuration or software errors after service or replacement can cause incorrect data, rejected inputs or loss of communication with other bridge equipment
- Mechanical damage or water ingress at exposed components can lead to erratic readings, repeated alarms or loss of the affected channel
- Sensor or antenna degradation caused by contamination, damage, ageing or poor exposure can produce missing, unstable or implausible data
- Connector, cable or network faults caused by vibration, corrosion or disturbed terminations can cause intermittent data loss or interface alarms
- Power-supply or internal electronics failure caused by ageing, heat or poor ventilation can result in resets, blank indications or complete loss of function
- Configuration or software errors after service or replacement can cause incorrect data, rejected inputs or loss of communication with other bridge equipment
- Mechanical damage or water ingress at exposed components can lead to erratic readings, repeated alarms or loss of the affected channel
- Loss of electrical, hydraulic, pneumatic, or other service supply caused by a tripped protection device, leakage, blockage, or upstream fault results in failed starting or loss of function
- Mechanical wear, corrosion, fouling, or contamination of moving and wetted parts causes increased noise, leakage, sticking, vibration, or reduced performance
- Seal, gasket, hose, cable, or connection deterioration from age, heat, vibration, or environmental exposure produces visible leakage, intermittent signals, or loss of pressure
- Sensor, switch, actuator, relay, or control-system faults can cause incorrect indication, nuisance alarms, failed automatic sequences, or loss of remote control
- Incorrect adjustment, assembly, or maintenance can lead to unstable operation, recurrent alarms, or performance that differs from the vessel's normal baseline
- Loss of electrical, hydraulic, pneumatic, or other service supply caused by a tripped protection device, leakage, blockage, or upstream fault results in failed starting or loss of function
- Mechanical wear, corrosion, fouling, or contamination of moving and wetted parts causes increased noise, leakage, sticking, vibration, or reduced performance
- Seal, gasket, hose, cable, or connection deterioration from age, heat, vibration, or environmental exposure produces visible leakage, intermittent signals, or loss of pressure
- Sensor, switch, actuator, relay, or control-system faults can cause incorrect indication, nuisance alarms, failed automatic sequences, or loss of remote control
- Incorrect adjustment, assembly, or maintenance can lead to unstable operation, recurrent alarms, or performance that differs from the vessel's normal baseline
SAM Electronics
7- Sensor or antenna fault caused by fouling, damage, wear or water ingress, resulting in loss, weak response or degraded navigation data
- Power-supply failure caused by breaker, converter or wiring problems, resulting in loss of indication
- Processor or display fault caused by electronics or software problems, resulting in frozen, blank or erroneous output
- Interface or network failure caused by cabling or configuration faults, resulting in missing data at connected bridge equipment
- Calibration, alignment or configuration error caused by incorrect setup or maintenance, resulting in persistent disagreement with independent navigation references
- Sensor or antenna fault caused by fouling, damage, wear or water ingress, resulting in loss, weak response or degraded navigation data
- Power-supply failure caused by breaker, converter or wiring problems, resulting in loss of indication
- Processor or display fault caused by electronics or software problems, resulting in frozen, blank or erroneous output
- Interface or network failure caused by cabling or configuration faults, resulting in missing data at connected bridge equipment
- Calibration, alignment or configuration error caused by incorrect setup or maintenance, resulting in persistent disagreement with independent navigation references
- Sensor or antenna fault caused by fouling, damage, wear or water ingress, resulting in loss, weak response or degraded navigation data
- Power-supply failure caused by breaker, converter or wiring problems, resulting in loss of indication
- Processor or display fault caused by electronics or software problems, resulting in frozen, blank or erroneous output
- Interface or network failure caused by cabling or configuration faults, resulting in missing data at connected bridge equipment
- Calibration, alignment or configuration error caused by incorrect setup or maintenance, resulting in persistent disagreement with independent navigation references
- Loss of electrical, hydraulic, pneumatic, or other service supply caused by a tripped protection device, leakage, blockage, or upstream fault results in failed starting or loss of function
- Mechanical wear, corrosion, fouling, or contamination of moving and wetted parts causes increased noise, leakage, sticking, vibration, or reduced performance
- Seal, gasket, hose, cable, or connection deterioration from age, heat, vibration, or environmental exposure produces visible leakage, intermittent signals, or loss of pressure
- Sensor, switch, actuator, relay, or control-system faults can cause incorrect indication, nuisance alarms, failed automatic sequences, or loss of remote control
- Incorrect adjustment, assembly, or maintenance can lead to unstable operation, recurrent alarms, or performance that differs from the vessel's normal baseline
- Loss of electrical, hydraulic, pneumatic, or other service supply caused by a tripped protection device, leakage, blockage, or upstream fault results in failed starting or loss of function
- Mechanical wear, corrosion, fouling, or contamination of moving and wetted parts causes increased noise, leakage, sticking, vibration, or reduced performance
- Seal, gasket, hose, cable, or connection deterioration from age, heat, vibration, or environmental exposure produces visible leakage, intermittent signals, or loss of pressure
- Sensor, switch, actuator, relay, or control-system faults can cause incorrect indication, nuisance alarms, failed automatic sequences, or loss of remote control
- Incorrect adjustment, assembly, or maintenance can lead to unstable operation, recurrent alarms, or performance that differs from the vessel's normal baseline
- Loss of electrical, hydraulic, pneumatic, or other service supply caused by a tripped protection device, leakage, blockage, or upstream fault results in failed starting or loss of function
- Mechanical wear, corrosion, fouling, or contamination of moving and wetted parts causes increased noise, leakage, sticking, vibration, or reduced performance
- Seal, gasket, hose, cable, or connection deterioration from age, heat, vibration, or environmental exposure produces visible leakage, intermittent signals, or loss of pressure
- Sensor, switch, actuator, relay, or control-system faults can cause incorrect indication, nuisance alarms, failed automatic sequences, or loss of remote control
- Incorrect adjustment, assembly, or maintenance can lead to unstable operation, recurrent alarms, or performance that differs from the vessel's normal baseline
- Sensor or antenna fault caused by fouling, damage, wear or water ingress, resulting in loss, weak response or degraded navigation data
- Power-supply failure caused by breaker, converter or wiring problems, resulting in loss of indication
- Processor or display fault caused by electronics or software problems, resulting in frozen, blank or erroneous output
- Interface or network failure caused by cabling or configuration faults, resulting in missing data at connected bridge equipment
- Calibration, alignment or configuration error caused by incorrect setup or maintenance, resulting in persistent disagreement with independent navigation references
Skipper Electronics
7- Sensor or antenna degradation caused by contamination, damage, ageing or poor exposure can produce missing, unstable or implausible data
- Connector, cable or network faults caused by vibration, corrosion or disturbed terminations can cause intermittent data loss or interface alarms
- Power-supply or internal electronics failure caused by ageing, heat or poor ventilation can result in resets, blank indications or complete loss of function
- Configuration or software errors after service or replacement can cause incorrect data, rejected inputs or loss of communication with other bridge equipment
- Mechanical damage or water ingress at exposed components can lead to erratic readings, repeated alarms or loss of the affected channel
- Sensor or antenna degradation caused by contamination, damage, ageing or poor exposure can produce missing, unstable or implausible data
- Connector, cable or network faults caused by vibration, corrosion or disturbed terminations can cause intermittent data loss or interface alarms
- Power-supply or internal electronics failure caused by ageing, heat or poor ventilation can result in resets, blank indications or complete loss of function
- Configuration or software errors after service or replacement can cause incorrect data, rejected inputs or loss of communication with other bridge equipment
- Mechanical damage or water ingress at exposed components can lead to erratic readings, repeated alarms or loss of the affected channel
- Sensor or antenna degradation caused by contamination, damage, ageing or poor exposure can produce missing, unstable or implausible data
- Connector, cable or network faults caused by vibration, corrosion or disturbed terminations can cause intermittent data loss or interface alarms
- Power-supply or internal electronics failure caused by ageing, heat or poor ventilation can result in resets, blank indications or complete loss of function
- Configuration or software errors after service or replacement can cause incorrect data, rejected inputs or loss of communication with other bridge equipment
- Mechanical damage or water ingress at exposed components can lead to erratic readings, repeated alarms or loss of the affected channel
- Loss of electrical, hydraulic, pneumatic, or other service supply caused by a tripped protection device, leakage, blockage, or upstream fault results in failed starting or loss of function
- Mechanical wear, corrosion, fouling, or contamination of moving and wetted parts causes increased noise, leakage, sticking, vibration, or reduced performance
- Seal, gasket, hose, cable, or connection deterioration from age, heat, vibration, or environmental exposure produces visible leakage, intermittent signals, or loss of pressure
- Sensor, switch, actuator, relay, or control-system faults can cause incorrect indication, nuisance alarms, failed automatic sequences, or loss of remote control
- Incorrect adjustment, assembly, or maintenance can lead to unstable operation, recurrent alarms, or performance that differs from the vessel's normal baseline
Sperry Marine
7- Loss of electrical, hydraulic, pneumatic, or other service supply caused by a tripped protection device, leakage, blockage, or upstream fault results in failed starting or loss of function
- Mechanical wear, corrosion, fouling, or contamination of moving and wetted parts causes increased noise, leakage, sticking, vibration, or reduced performance
- Seal, gasket, hose, cable, or connection deterioration from age, heat, vibration, or environmental exposure produces visible leakage, intermittent signals, or loss of pressure
- Sensor, switch, actuator, relay, or control-system faults can cause incorrect indication, nuisance alarms, failed automatic sequences, or loss of remote control
- Incorrect adjustment, assembly, or maintenance can lead to unstable operation, recurrent alarms, or performance that differs from the vessel's normal baseline
- Loss of electrical, hydraulic, pneumatic, or other service supply caused by a tripped protection device, leakage, blockage, or upstream fault results in failed starting or loss of function
- Mechanical wear, corrosion, fouling, or contamination of moving and wetted parts causes increased noise, leakage, sticking, vibration, or reduced performance
- Seal, gasket, hose, cable, or connection deterioration from age, heat, vibration, or environmental exposure produces visible leakage, intermittent signals, or loss of pressure
- Sensor, switch, actuator, relay, or control-system faults can cause incorrect indication, nuisance alarms, failed automatic sequences, or loss of remote control
- Incorrect adjustment, assembly, or maintenance can lead to unstable operation, recurrent alarms, or performance that differs from the vessel's normal baseline
- Loss of electrical, hydraulic, pneumatic, or other service supply caused by a tripped protection device, leakage, blockage, or upstream fault results in failed starting or loss of function
- Mechanical wear, corrosion, fouling, or contamination of moving and wetted parts causes increased noise, leakage, sticking, vibration, or reduced performance
- Seal, gasket, hose, cable, or connection deterioration from age, heat, vibration, or environmental exposure produces visible leakage, intermittent signals, or loss of pressure
- Sensor, switch, actuator, relay, or control-system faults can cause incorrect indication, nuisance alarms, failed automatic sequences, or loss of remote control
- Incorrect adjustment, assembly, or maintenance can lead to unstable operation, recurrent alarms, or performance that differs from the vessel's normal baseline
- Loss of electrical, hydraulic, pneumatic, or other service supply caused by a tripped protection device, leakage, blockage, or upstream fault results in failed starting or loss of function
- Mechanical wear, corrosion, fouling, or contamination of moving and wetted parts causes increased noise, leakage, sticking, vibration, or reduced performance
- Seal, gasket, hose, cable, or connection deterioration from age, heat, vibration, or environmental exposure produces visible leakage, intermittent signals, or loss of pressure
- Sensor, switch, actuator, relay, or control-system faults can cause incorrect indication, nuisance alarms, failed automatic sequences, or loss of remote control
- Incorrect adjustment, assembly, or maintenance can lead to unstable operation, recurrent alarms, or performance that differs from the vessel's normal baseline
- Loss of electrical, hydraulic, pneumatic, or other service supply caused by a tripped protection device, leakage, blockage, or upstream fault results in failed starting or loss of function
- Mechanical wear, corrosion, fouling, or contamination of moving and wetted parts causes increased noise, leakage, sticking, vibration, or reduced performance
- Seal, gasket, hose, cable, or connection deterioration from age, heat, vibration, or environmental exposure produces visible leakage, intermittent signals, or loss of pressure
- Sensor, switch, actuator, relay, or control-system faults can cause incorrect indication, nuisance alarms, failed automatic sequences, or loss of remote control
- Incorrect adjustment, assembly, or maintenance can lead to unstable operation, recurrent alarms, or performance that differs from the vessel's normal baseline
Tokyo Keiki
7- Sensor fouling, marine growth or damage causes low, erratic or missing speed readings
- Cabling or transducer faults cause intermittent data or complete loss of speed indication
- Incorrect calibration or setup causes a persistent difference from expected vessel speed
- Processor or display faults cause frozen values, alarms or loss of output to other bridge systems
- Air bubbles, aeration or disturbed water flow around the sensor cause unstable readings under certain operating conditions
- Sensor fouling, marine growth or damage causes low, erratic or missing speed readings
- Cabling or transducer faults cause intermittent data or complete loss of speed indication
- Incorrect calibration or setup causes a persistent difference from expected vessel speed
- Processor or display faults cause frozen values, alarms or loss of output to other bridge systems
- Air bubbles, aeration or disturbed water flow around the sensor cause unstable readings under certain operating conditions
- Sensor fouling, marine growth or damage causes low, erratic or missing speed readings
- Cabling or transducer faults cause intermittent data or complete loss of speed indication
- Incorrect calibration or setup causes a persistent difference from expected vessel speed
- Processor or display faults cause frozen values, alarms or loss of output to other bridge systems
- Air bubbles, aeration or disturbed water flow around the sensor cause unstable readings under certain operating conditions
- Sensor, antenna or transducer fouling, damage or misalignment causes unstable, missing or inaccurate data
- Power-supply or processor faults cause resets, blank displays or complete loss of indication
- Cable, connector or network faults cause intermittent data or loss of outputs to other bridge systems
- Incorrect configuration or calibration causes persistent disagreement with independent references
- Display or software faults cause frozen values, alarms or unavailable functions
- Sensor or antenna fault caused by fouling, damage, wear or water ingress, resulting in loss, weak response or degraded navigation data
- Power-supply failure caused by breaker, converter or wiring problems, resulting in loss of indication
- Processor or display fault caused by electronics or software problems, resulting in frozen, blank or erroneous output
- Interface or network failure caused by cabling or configuration faults, resulting in missing data at connected bridge equipment
- Calibration, alignment or configuration error caused by incorrect setup or maintenance, resulting in persistent disagreement with independent navigation references
- Loss of electrical, hydraulic, pneumatic, or other service supply caused by a tripped protection device, leakage, blockage, or upstream fault results in failed starting or loss of function
- Mechanical wear, corrosion, fouling, or contamination of moving and wetted parts causes increased noise, leakage, sticking, vibration, or reduced performance
- Seal, gasket, hose, cable, or connection deterioration from age, heat, vibration, or environmental exposure produces visible leakage, intermittent signals, or loss of pressure
- Sensor, switch, actuator, relay, or control-system faults can cause incorrect indication, nuisance alarms, failed automatic sequences, or loss of remote control
- Incorrect adjustment, assembly, or maintenance can lead to unstable operation, recurrent alarms, or performance that differs from the vessel's normal baseline
- Sensor fouling, marine growth or damage causes low, erratic or missing speed readings
- Cabling or transducer faults cause intermittent data or complete loss of speed indication
- Incorrect calibration or setup causes a persistent difference from expected vessel speed
- Processor or display faults cause frozen values, alarms or loss of output to other bridge systems
- Air bubbles, aeration or disturbed water flow around the sensor cause unstable readings under certain operating conditions
JRC (Japan Radio Co)
6- Loss of electrical, hydraulic, pneumatic, or other service supply caused by a tripped protection device, leakage, blockage, or upstream fault results in failed starting or loss of function
- Mechanical wear, corrosion, fouling, or contamination of moving and wetted parts causes increased noise, leakage, sticking, vibration, or reduced performance
- Seal, gasket, hose, cable, or connection deterioration from age, heat, vibration, or environmental exposure produces visible leakage, intermittent signals, or loss of pressure
- Sensor, switch, actuator, relay, or control-system faults can cause incorrect indication, nuisance alarms, failed automatic sequences, or loss of remote control
- Incorrect adjustment, assembly, or maintenance can lead to unstable operation, recurrent alarms, or performance that differs from the vessel's normal baseline
- Loss of electrical, hydraulic, pneumatic, or other service supply caused by a tripped protection device, leakage, blockage, or upstream fault results in failed starting or loss of function
- Mechanical wear, corrosion, fouling, or contamination of moving and wetted parts causes increased noise, leakage, sticking, vibration, or reduced performance
- Seal, gasket, hose, cable, or connection deterioration from age, heat, vibration, or environmental exposure produces visible leakage, intermittent signals, or loss of pressure
- Sensor, switch, actuator, relay, or control-system faults can cause incorrect indication, nuisance alarms, failed automatic sequences, or loss of remote control
- Incorrect adjustment, assembly, or maintenance can lead to unstable operation, recurrent alarms, or performance that differs from the vessel's normal baseline
- Loss of electrical, hydraulic, pneumatic, or other service supply caused by a tripped protection device, leakage, blockage, or upstream fault results in failed starting or loss of function
- Mechanical wear, corrosion, fouling, or contamination of moving and wetted parts causes increased noise, leakage, sticking, vibration, or reduced performance
- Seal, gasket, hose, cable, or connection deterioration from age, heat, vibration, or environmental exposure produces visible leakage, intermittent signals, or loss of pressure
- Sensor, switch, actuator, relay, or control-system faults can cause incorrect indication, nuisance alarms, failed automatic sequences, or loss of remote control
- Incorrect adjustment, assembly, or maintenance can lead to unstable operation, recurrent alarms, or performance that differs from the vessel's normal baseline
- Sensor or antenna degradation caused by contamination, damage, ageing or poor exposure can produce missing, unstable or implausible data
- Connector, cable or network faults caused by vibration, corrosion or disturbed terminations can cause intermittent data loss or interface alarms
- Power-supply or internal electronics failure caused by ageing, heat or poor ventilation can result in resets, blank indications or complete loss of function
- Configuration or software errors after service or replacement can cause incorrect data, rejected inputs or loss of communication with other bridge equipment
- Mechanical damage or water ingress at exposed components can lead to erratic readings, repeated alarms or loss of the affected channel
- Sensor or antenna degradation caused by contamination, damage, ageing or poor exposure can produce missing, unstable or implausible data
- Connector, cable or network faults caused by vibration, corrosion or disturbed terminations can cause intermittent data loss or interface alarms
- Power-supply or internal electronics failure caused by ageing, heat or poor ventilation can result in resets, blank indications or complete loss of function
- Configuration or software errors after service or replacement can cause incorrect data, rejected inputs or loss of communication with other bridge equipment
- Mechanical damage or water ingress at exposed components can lead to erratic readings, repeated alarms or loss of the affected channel
Consilium Marine
5- Loss of electrical, hydraulic, pneumatic, or other service supply caused by a tripped protection device, leakage, blockage, or upstream fault results in failed starting or loss of function
- Mechanical wear, corrosion, fouling, or contamination of moving and wetted parts causes increased noise, leakage, sticking, vibration, or reduced performance
- Seal, gasket, hose, cable, or connection deterioration from age, heat, vibration, or environmental exposure produces visible leakage, intermittent signals, or loss of pressure
- Sensor, switch, actuator, relay, or control-system faults can cause incorrect indication, nuisance alarms, failed automatic sequences, or loss of remote control
- Incorrect adjustment, assembly, or maintenance can lead to unstable operation, recurrent alarms, or performance that differs from the vessel's normal baseline
- Loss of electrical, hydraulic, pneumatic, or other service supply caused by a tripped protection device, leakage, blockage, or upstream fault results in failed starting or loss of function
- Mechanical wear, corrosion, fouling, or contamination of moving and wetted parts causes increased noise, leakage, sticking, vibration, or reduced performance
- Seal, gasket, hose, cable, or connection deterioration from age, heat, vibration, or environmental exposure produces visible leakage, intermittent signals, or loss of pressure
- Sensor, switch, actuator, relay, or control-system faults can cause incorrect indication, nuisance alarms, failed automatic sequences, or loss of remote control
- Incorrect adjustment, assembly, or maintenance can lead to unstable operation, recurrent alarms, or performance that differs from the vessel's normal baseline
- Loss of electrical, hydraulic, pneumatic, or other service supply caused by a tripped protection device, leakage, blockage, or upstream fault results in failed starting or loss of function
- Mechanical wear, corrosion, fouling, or contamination of moving and wetted parts causes increased noise, leakage, sticking, vibration, or reduced performance
- Seal, gasket, hose, cable, or connection deterioration from age, heat, vibration, or environmental exposure produces visible leakage, intermittent signals, or loss of pressure
- Sensor, switch, actuator, relay, or control-system faults can cause incorrect indication, nuisance alarms, failed automatic sequences, or loss of remote control
- Incorrect adjustment, assembly, or maintenance can lead to unstable operation, recurrent alarms, or performance that differs from the vessel's normal baseline
- Loss of electrical, hydraulic, pneumatic, or other service supply caused by a tripped protection device, leakage, blockage, or upstream fault results in failed starting or loss of function
- Mechanical wear, corrosion, fouling, or contamination of moving and wetted parts causes increased noise, leakage, sticking, vibration, or reduced performance
- Seal, gasket, hose, cable, or connection deterioration from age, heat, vibration, or environmental exposure produces visible leakage, intermittent signals, or loss of pressure
- Sensor, switch, actuator, relay, or control-system faults can cause incorrect indication, nuisance alarms, failed automatic sequences, or loss of remote control
- Incorrect adjustment, assembly, or maintenance can lead to unstable operation, recurrent alarms, or performance that differs from the vessel's normal baseline
- Loss of electrical, hydraulic, pneumatic, or other service supply caused by a tripped protection device, leakage, blockage, or upstream fault results in failed starting or loss of function
- Mechanical wear, corrosion, fouling, or contamination of moving and wetted parts causes increased noise, leakage, sticking, vibration, or reduced performance
- Seal, gasket, hose, cable, or connection deterioration from age, heat, vibration, or environmental exposure produces visible leakage, intermittent signals, or loss of pressure
- Sensor, switch, actuator, relay, or control-system faults can cause incorrect indication, nuisance alarms, failed automatic sequences, or loss of remote control
- Incorrect adjustment, assembly, or maintenance can lead to unstable operation, recurrent alarms, or performance that differs from the vessel's normal baseline