DH-V Type Electrically Controlled Gyrocompass

1. Product Number: DH-V Type Electrically Controlled Gyrocompass

2. Brief introduction:

The DH-V type electrically controlled gyrocompass is a navigation device that uses a two-degree-of-freedom gyroscope and an electromagnetic pendulum as sensing elements. It leverages the unique characteristics of the gyroscope and the规律 of Earth’s rotation to automatically find north and maintain stable north-seeking capability. This device employs digital control technology in areas such as automatic north-seeking and error compensation, making it easy to operate and highly stable and reliable.

3. Main functions:

a) Automatic North-Finding Function: The gyrocompass leverages the gyroscopic properties and the Earth’s rotation规律 to enable the gyroscopic spin axis, via a control system, to automatically and rapidly find north.

b) Automatic compensation function for latitude and velocity errors;

c) Heading value display (indication) function;

d) Interface function: The interface function to send heading signals to the load;

e) Alarm functions: Includes alarms for gyroscope power failure, servo system failure, internal CAN network error, abnormal heading angular velocity, and abnormal input speed/latitude information.

4. Classification Society Certificate: CCS Ship Inspection Certificate

5. Key performance indicators:

The main performance indicators of the DH-V type electrically controlled gyrocompass meet the requirements of IMO Resolution A.424(XI), “Performance Standards for Electric Gyrocompasses,” and ISO 8728:1997, “Marine and Offshore Technology—Marine Gyrocompasses,” as detailed below:

a) Precision metric

Settling time: 2 hours on a stationary horizontal base, 2.5 hours on a moving base.

Stability point error: ±0.75° × SecΦ

Heading deviation: 0.25° × SecΦ

Repeatability accuracy of the stable point error: 0.25° × SecΦ

Repeatability stability point error under normal conditions: ±1° × SecΦ

Residual error of the gyrocompass after speed correction: ±0.25° × SecΦ

Error caused by a rapid change in speed of 20 kN: ±2°

At a speed of 20 knots, the error caused by rapidly changing course by 180°: ±3°

Swing error: ±1° × SecΦ

Compass re-reading accuracy: ±0.5°

b) Scope of Work

Applicable latitude: 0° to 60° north and south latitudes

Applicable speed: 0–40 knots

Applicable ship power supply: Main power AC 220V ±10% / 47–63Hz

Emergency power supply DC 24V (18V～31V)

6. Instrument accessories:

Basic Composition Table for DH-V Type Electrically Controlled Gyrocompass

7. Interface Protocol

7.1 Input Signal

7.1.1 Speed/Latitude Information

The DH-V type electrically controlled gyrocompass can receive speed and latitude information from GPS or Beidou, enabling automatic compensation for latitude and velocity errors. The interface conventions are as follows:

Complies with the EIA RS-422A interface communication standard;

Complies with NMEA-0183 standard (V2.00);

Serial, asynchronous, unidirectional communication mode;

Communication baud rate: 4.8 Kbit/s (adjustable);

7.1.2 Magnetic Compass Heading Information

The DH-V type electrically controlled gyrocompass can receive heading information from the magnetic compass and retransmit it externally. The interface specifications are as follows:

Complies with the EIA RS-422A interface communication standard;

Complies with NMEA-0183 standard (V2.00);

It employs a serial, asynchronous, unidirectional communication mode.

Communication baud rate: 4.8 Kbit/s (adjustable);

7.2 Output Signal

7.2.1 Compass Interface – Compass Interface

Four-way gyrocompass interface signals are transmitted externally. Each signal includes a set of DC24V power supply and a set of RS422 heading information. The interface specifications are as follows:

a) DC 24V power supply

Voltage range: DC 24V ±10%

Maximum power consumption: 10W/channel

b) Heading information

Complies with the EIA RS-422A interface communication standard;

Complies with NMEA-0183 standard (V2.00);

Serial, asynchronous, unidirectional communication mode;

Communication baud rate: 4.8 Kbit/s;

7.2.2 Heading Information

Eight-channel RS422 heading information is transmitted externally. The interface specifications are as follows:

Complies with the EIA RS-422A interface communication standard;

Complies with NMEA-0183 standard (V2.00);

Serial, asynchronous, unidirectional communication mode;

Communication baud rate: 4.8 Kbit/s;

8. System Connection Diagram and Installation Layout Diagram