sensitive Element
Tokyo Keiki Inc. — formerly branded TOKIMEC
Refurbished
Manufacturer: Tokyo Keiki Inc. — formerly branded TOKIMEC
Country of Origin: Japan
System Model: TG-8000 Series
Component: Gyrocompass Sensitive Element / Gyro Sphere Assembly
Visible Marking on SM MARINE SERVICE™ Unit: GY141R4SF
Product Type: Marine Gyrocompass Sensitive Element
Marine Application: True-heading detection for ship navigation, autopilot, radar, ECDIS, repeaters and other heading-dependent bridge equipment.
The uploaded SM MARINE SERVICE™ photograph clearly shows “MADE IN JAPAN TOKYO KEIKI” and the visible identifier GY141R4SF on the sensitive element.
The Tokyo Keiki / TOKIMEC TG-8000 Sensitive Element is one of the most important precision components inside the TG-8000 marine gyrocompass master compass.
The TG-8000 series was developed from Tokyo Keiki's earlier TG-5000/6000 gyrocompass technology for medium and large vessels. Its documented functions include automatic speed-error correction, digital signal processing, IEC 61162-compatible communications and multiple heading outputs.
The sensitive element is effectively the heart of the gyrocompass. Its gyro mechanism establishes the heading reference from which the complete TG-8000 system derives true-heading information.
The unit shown in the supplied photograph is an actual Tokyo Keiki sensitive element with the internal precision assembly, electrical contacts, flexible circuit paths and transparent lower housing visible.
Because the visible marking is GY141R4SF, buyers looking for an exact replacement should compare this marking—as well as their master-compass serial/configuration information—before ordering.
The sensitive element is installed inside the TG-8000 Master Compass. The manufacturer documentation describes the master compass as the unit that detects the ship's heading and confirms that the sensitive element is built into that assembly.
Its operation forms the primary heading reference that the TG-8000 subsequently distributes to other navigation equipment.
Typical consumers of gyro heading can include:
Autopilot • Radar • ARPA • ECDIS • VDR/S-VDR • AIS • Bearing Repeaters • Digital Repeaters • Steering Systems • Bridge Navigation Equipment
The TG-8000 gyrocompass platform provides several important marine-navigation capabilities:
Tokyo Keiki documentation identifies TG-8000/8500-S as a one-gyro system and TG-8000/8500-D as a two-gyro system.
Published TG-8000/8500 technical documentation lists:
| Specification | TG-8000 Series |
|---|---|
| Main Power | AC 100/110/115/220 V, 1-phase, 50/60 Hz |
| Emergency Power | DC 24 V |
| Starting Consumption | Approx. 140 VA |
| Operating Consumption | Approx. 70 VA |
| Step Repeater Output | DC 24 V |
| Serial Interface | IEC 61162 |
| Master Compass Mass | Approx. 23 kg |
| Control Unit Mass | Approx. 16 kg for Type S |
These figures describe the TG-8000 system, not the standalone GY141R4SF sensitive element.
The precision gyro assembly responsible for establishing the primary heading reference.
Houses the sensitive element and associated mechanical/electrical components.
Provides system operation, indications, alarms and interface functions.
Supplies operating power to the master compass and associated electronics, with emergency DC supply provision.
Distribute heading information to compatible bridge systems.
The TG-8000 type approval documentation also identifies compatible system equipment including AGI-50 / AGI-80 interface units, UD-10 / UD-100 universal displays and DR-10 / DR-100 / DR-110 digital repeaters.
The TG-8000 is suitable for heading-reference applications aboard:
Container Ships • Bulk Carriers • Tankers • General Cargo Ships • Passenger Ships • Offshore Vessels • Merchant Ships and other commercial vessels
Reliable gyro heading is particularly important because multiple bridge systems may depend on the same heading information.
A sensitive-element problem can therefore affect much more than the gyro display itself.
Possible areas requiring inspection include the sensitive element, its electrical connections, mechanical condition, master-compass components, supply voltage and system parameters.
The heading should always be compared with other reliable heading references before assuming the sensitive element itself has failed.
Check the startup process, sensitive-element operation, power supply and mechanical freedom of the master compass.
The maintenance documentation includes specific Sensitive Element Check and Start-up Sequence Check procedures.
Inspect the repeater supply, interface circuits, wiring and output configuration before replacing the sensitive element.
The TG-8000 maintenance documentation specifies checking both main and backup supplies and contains detailed internal voltage tests.
Maintenance documentation specifically covers components such as:
Step Motor • Brushes • Slip Rings • Sensitive Element
It also contains procedures for brush replacement, slip-ring cleaning, slip-ring replacement and sensitive-element replacement.
Replacement should be considered only after proper diagnosis. A gyrocompass is precision navigation equipment, so installation, parameter verification and functional checks should be performed by competent marine-navigation technicians.
The TG-8000 incorporates alarm monitoring, and Tokyo Keiki's operator documentation instructs users to investigate the cause whenever the alarm system activates rather than simply continuing operation.
Possible fault areas include:
Sensitive Element • Master Compass • Power Supply • Heading Output • Repeater Circuit • Control Electronics • External Input • Interface Communication
Exact alarm indications should be interpreted using the appropriate TG-8000 manual and vessel-specific configuration rather than assuming a generic fault.
The TG-8000 operator manual emphasizes daily checking, while the dedicated maintenance documentation provides more extensive inspection procedures.
Recommended attention includes checking:
Sensitive-element removal or internal adjustment should not be treated as routine crew maintenance.
For existing Tokyo Keiki / TOKIMEC TG-8000 installations, SM MARINE SERVICE™ can assist with sourcing compatible equipment subject to availability, including:
TG-8000 Sensitive Element • Gyro Sphere • Master Compass • Complete TG-8000 Gyrocompass • Control Unit • Power Supply Components • PCB Assemblies • Interface Units • Step Motor • Slip Ring Components • Brushes • Repeater Components • Cables • Connectors • Internal Electronic and Mechanical Parts
For an exact GY141R4SF sensitive-element inquiry, buyers should ideally send:
1. Existing sensitive-element photograph
2. Full marking/part number
3. TG-8000 master-compass nameplate
4. Serial number
5. Vessel's current system configuration
This reduces the risk of supplying an incompatible revision.
SM MARINE SERVICE™ can support sourcing of New, Used, Refurbished, Reconditioned and Tested Working Equipment, depending on stock and availability.
The TG-8000 remains relevant aboard vessels where an established gyrocompass installation is still operational and serviceable.
Replacing a failed sensitive element or another compatible component can sometimes be more practical than replacing the complete gyrocompass installation—particularly where the existing TG-8000 already interfaces with autopilot, radar, repeaters and other bridge equipment.
Its documented architecture also provides multiple repeater outputs, serial communication, automatic speed-error correction and emergency power capability.
What is the Tokyo Keiki TG-8000 Sensitive Element?
It is the precision gyro-sensitive assembly installed within the TG-8000 master compass and is central to determining the vessel's heading.
Who manufactures the TG-8000?
The TG-8000 is a Japanese gyrocompass system from Tokyo Keiki, historically also known under the TOKIMEC name.
What marking is visible on the SM MARINE SERVICE™ sensitive element?
The supplied unit visibly carries GY141R4SF together with MADE IN JAPAN TOKYO KEIKI.
Where can I buy a TG-8000 Sensitive Element?
SM MARINE SERVICE™ can assist international buyers with sourcing TG-8000 sensitive elements, gyro spheres and related spare parts subject to stock availability.
Can I buy a used or reconditioned TG-8000 sensitive element?
Yes, used, tested, refurbished or reconditioned equipment may be sourced depending on availability and the required configuration.
Can the sensitive element be replaced separately?
Yes. Tokyo Keiki's maintenance documentation includes a specific sensitive-element replacement procedure.
Are TG-8000 service and maintenance manuals available?
Yes. Operator, maintenance and service documentation exists for the TG-8000 series.
Can SM MARINE SERVICE™ supply TG-8000 spare parts worldwide?
SM MARINE SERVICE™ supports international sourcing and worldwide shipment of marine navigation equipment and replacement parts subject to availability.
The Tokyo Keiki / TOKIMEC TG-8000 Gyrocompass Sensitive Element is a precision internal gyro assembly used within the TG-8000 marine gyrocompass master compass to establish the vessel's true-heading reference. The SM MARINE SERVICE™ unit shown carries the visible marking GY141R4SF and Made in Japan – Tokyo Keiki. TG-8000 sensitive elements, gyro spheres, master compasses, control units and related replacement spare parts can be sourced in various conditions subject to availability.
Marine Automation & Navigation Equipment Supplier
Available Condition:
• New Equipment • Used Equipment • Refurbished Equipment • Reconditioned Equipment
Stock Location:
• Bangladesh • China
Services:
• Worldwide Shipping • Technical Support • Spare Parts Supply • Marine Equipment Sourcing
Contact Information
SM MARINE SERVICE™ Samir Market, DT Road, Pahartali, beside CDA Market, Chattogram, Bangladesh
Mobile / WhatsApp / Viber: +88 01818 929292
Email: info@smmarineservice.com
Website: www.smmarineservice.com
0
BDT 0
BDT 0
BDT 0
BDT 0
Marine Equipment Supplier