{"id":2517,"date":"2023-01-24T13:29:54","date_gmt":"2023-01-24T13:29:54","guid":{"rendered":"http:\/\/test-wp.hanse-survey.de\/uncategorized\/magnetic-compass-adjustment\/"},"modified":"2026-03-25T06:53:04","modified_gmt":"2026-03-25T06:53:04","slug":"magnetic-compass-adjustment","status":"publish","type":"post","link":"https:\/\/hanse-survey.de\/en\/compass-overview\/magnetic-compass-adjustment\/","title":{"rendered":"Magnetic compass adjustment"},"content":{"rendered":"

Appointed adjuster of the German Federal <\/strong>Maritime and Hydrographic Agency.<\/strong><\/h2>\n

As only one of seven members of the Association of German Compass adjusters in Germany and approved by the German Federal Maritime and Hydrographic Agency as a recognised compass adjuster, Hanse Survey will gladly take over the adjustment & compensation of your magnetic compasses on board.<\/p>\n

Regular and professional regulation is essential for the safe operation of the vessel, as it ensures that the magnetic compass can be safely used for navigation in the event of a power failure.<\/p>\n<\/div><\/div><\/div>

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How does a magnetic compass work?<\/strong><\/h2>\n

A magnetic compass automatically aligns itself to magnetic north due to the earth’s magnetic field. To avoid distortions of the course read, it is important that the compass is not influenced by other magnetic fields. However, this is impossible on a ship, so the magnetic field of the ship is compensated for as far as possible with the help of correction magnets at the compass installation site, with a remaining limited error (deviation) the correct course is displayed. However, the magnetic field generated by the compensating magnets is less complex than the magnetic field of the ship, which is why minor deviations can appear. These minimal deviations are documented, in 10\u00b0 steps, by our experienced adjuster in a deviation table. Based on the values in the table, it is therefore possible to determine the course that has to be steered.<\/p>\n<\/div><\/div><\/div>

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Example: <\/strong><\/p>\n

True heading: 90\u00b0
\nDeviation according to table: +1\u00b0<\/p>\n

Variation (indication from nautical chart): +3\u00b0 (E)
\nMagnetic compass heading to steer: 90\u00b0 – (+3\u00b0) – (+1\u00b0) = 86\u00b0.<\/p>\n<\/div><\/div><\/div><\/div><\/div>

\"Bearing<\/a><\/div><\/div><\/div><\/div>
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How are the deviations determined<\/strong>?<\/h2>\n

To adjust the compass, the ship must perform two full circles. Our compass adjuster takes a bearing over a prominent fixed object in the vicinity, e.g. a church or a high-rise building. Based on this bearing, the deviation can be determined with the help of the right-pointing bearing to the wrong-pointing bearing.<\/p>\n

In this procedure, we follow the generally recognised guidelines and standards.<\/p>\n<\/div><\/div><\/div><\/div><\/div>

SOLAS Chapter V Regulation 19 Paragraph 2<\/strong><\/h2>\n

Paragraphs 2.1, 2.1.1, 2.1.2, 2.1.3 state that all ships irrespective of size shall have:<\/p>\n

A properly adjusted standard magnetic compass, or other means, independent of any power supply, to determine the ships heading and display the reading at the main steering position.<\/p>\n

A pelorus or compass bearing device, or other means, independent of any power supply, to take bearings over an arc of the horizon of 360\u00b0.<\/p>\n

Means of correcting heading and bearings to true at all times.<\/p>\n<\/div><\/div><\/div>

\"BBC<\/a><\/div><\/div><\/div><\/div>
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ISO 25862<\/strong><\/h2>\n

G1. General<\/span><\/b><\/h3>\n

A properly adjusted compass shall have a residual deviation within 3\u00b0 in vessels 500 or more gross tonnage and, +\/- 4\u00b0 in vessels below 500 gross tonnage. Accuracies shall be within +\/- 2\u00b0 for safe navigation. A special regulation applies to inland vessels, where the maximum residual deviation may be +\/- 6\u00b0.<\/p>\n

The location of the compass on board the vessel is not insignificant for ensuring reliable operation of the magnetic compass. It is particularly important to ensure that the magnetic free zone around the compass is complied during building and esured during operation.<\/p>\n

This is a distance of the magnetic compass to any magnetic materials. This distance should be assumed to be spherical around the compass. Accordingly, A-magnetic steel or other non-magnetic materials should be used within this area.<\/p>\n

Furthermore, the distance to electronic devices, also called “magnetic safe distance”, must be taken into account. This distance is indicated on the back of every electronic device used in merchant shipping.<\/p>\n

G2. Magnetic compasses should be adjusted when: <\/strong><\/h3>\n