Yokogawa Gyro Compass Cmz 700 User Manual «2025-2026»
The Yokogawa CMZ700 Gyro Compass is a high-performance marine navigation system designed for diverse vessel types, from small yachts to large commercial ships. It is available in three primary configurations—CMZ700B (Basic), CMZ700S (Single), and CMZ700D (Dual)—to meet varying reliability and interface needs. System Configurations
CMZ700B: A compact, basic version where the master compass directly drives repeaters without a separate control box.
CMZ700S: Includes a control box for expanded input/output capabilities, making it adaptable for any vessel tonnage.
CMZ700D: Features a dual-unit setup for enhanced reliability and redundancy in critical navigation scenarios. Key Technical Specifications Specification Settling Time
Full meridian settling within 5 hours; operational within 2 hours. Static Accuracy Follow-up Speed High-speed response of up to , ideal for sharp-turning vessels. Power Supply
Typically 24V DC (ship's battery) with optional AC adapters (100V–230V). Environmental Limits Operating temperature: -10∘Cnegative 10 raised to the composed with power cap C +55∘Cpositive 55 raised to the composed with power cap C ; Max roll/pitch: ±40∘plus or minus 40 raised to the composed with power Operational Highlights yokogawa gyro compass cmz 700 user manual
Anti-Vibration System: Uses a unique viscous oil-damping mechanism to reduce the impact of external interference and vibrations at sea.
Modular Design: The master unit (MKM 022) is compact (350 x 460 x 360 mm) and can often be integrated directly into autopilot steering stands.
External Heading Backup: Capable of switching to external heading sensors to maintain signals to repeaters in the event of a gyro failure.
Restart Timer: Allows users to preset a restart time ranging from 1 to 99 hours. Maintenance and Troubleshooting CMZ 700 Gyrocompass
SYSTEM CONFIGURATION. MASTER COMPASS. (MKM 022) 2345. Ship's speed (200 P/nm. or IEC61162) Latitude (IEC61162) External heading. ( CMZ700 Gyrocompass Specifications Guide | PDF - Scribd The Yokogawa CMZ700 Gyro Compass is a high-performance
4. Maintenance: The "Manual's Blind Spot"
The Yokogawa CMZ-700 manual is excellent for operations but deliberately vague on repair. The reason is the Gyrosphere: a sealed, helium-filled beryllium-copper sphere spinning at 20,000 RPM.
- Manual’s stance: "Replace the gyrosphere as an assembly. Do not open."
- Reality: The manual provides no calibration procedure for the pick-offs (signal generators). If the output voltage deviates from the spec (usually 1V per degree of tilt), the manual tells you to send the unit to a Yokogawa service center.
- The Master-Slave Logic: For vessels using multiple repeaters, the manual details "Repeater synchronization." What it doesn't say is that the CMZ-700 uses a three-wire synchro system. If the S1, S2, S3 wires are swapped, the repeater will spin continuously. The manual's wiring diagram is the only defense against this.
9.2 Certifications
- MED (Wheelmark) – Module B + D
- IEC 60945 (Marine navigation equipment)
- FCC Part 15 Class A
- RoHS compliant
Part 7: The Future – Is the CMZ 700 Still Relevant?
Yokogawa discontinued the CMZ series in favor of fiber-optic gyro compasses (FOG) like the TG-8000, which have no moving parts. However, thousands of CMZ 700 units are still operational on vessels worldwide because of their legendary durability.
Pros of keeping the CMZ 700:
- No GPS dependency (unlike some modern FOGs that require GNSS for initial alignment).
- Extremely low drift rate (0.1° per hour).
- Repairable by any competent marine electrician with the user manual.
Cons:
- Requires yearly mercury lamp replacement.
- Mercury handling is increasingly regulated under MARPOL.
- Parts are becoming scarce.
For owners continuing to use this unit, the Yokogawa Gyro Compass CMZ 700 user manual is the single most critical item for extending its service life. Without it, a simple battery replacement (for memory backup) becomes a dangerous guessing game. Manual’s stance: "Replace the gyrosphere as an assembly
Key Technical Specifications (as per the manual)
- Settling Time: Less than 3 hours (from power-on to steady-state accuracy)
- Latitude Error: Automatically compensated up to 85° North/South
- Speed Error: Automatic compensation via speed log input
- Follow-up System: Step motor-driven, digital follow-up
- Alarms: Muting function for passing maneuvers
The user manual dedicates significant space to these specifications because understanding the physical limitations of the device ensures proper usage. For instance, the manual warns that while the settling time is listed as 3 hours, the compass may require additional time to stabilize if the vessel undergoes extreme maneuvering immediately after start-up.
2.2 Mounting Requirements
- Location: As close as possible to vessel’s center of rotation, ideally on a rigid deck or bulkhead.
- Environment: Free from strong magnetic fields (e.g., degaussing cables, high-current switchboards), vibration < 0.5g, temperature within spec.
- Orientation: Alignment marks on casing must point exactly to vessel’s bow (forward). Tolerance ±0.5°.
Mounting steps:
- Mark drill holes using supplied template.
- Secure base plate with M10 stainless steel bolts.
- Place master unit on base plate, tighten locking screws.
- Use spirit level to ensure horizontal alignment (max tilt 1°).
Introduction: Beyond the Paper
In the world of marine navigation, the Gyro Compass is not merely a tool; it is the philosophical north of the vessel’s situational awareness. The Yokogawa CMZ-700 represents a specific era of Japanese maritime engineering—where analog redundancy met early digital logic. However, for the marine superintendent, navigating officer, or maintenance engineer, the device is only as reliable as the documentation that governs its operation.
The User Manual for the CMZ-700 is not a "quick start guide." It is a legal, technical, and operational covenant. This article dissects what a user must truly understand about this manual, from safety interlocks to spurious north-seeking errors.