Cabling Documents, EMC Purposes, Protective Ground

MX535 UAIS Transponder Unit

Technical & Installation Manual

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8 Cabling Documents

Grounding

Grounding connection is important for EMC purposes as well as for protecting people’s lives.

Regardless of the type of ship’s grounding (e.g. star pattern or ground plane pattern), no potential difference should be measurable between two different ground connectors. Potential differences cause compensation currents on the cable shields. If the ship’s hull is a non-metallic structure, all metallic parts in contact with the water form an artificial ground.

All ground connections should be as short as possible. If possible, different units should be connected to individual ground connectors. Whenever possible, metallic housings should be screwed or welded directly to the ship’s metallic structure. If a safe grounding contact is not ensured, additional conductors are necessary. Furthermore, all ground connections should have a low RF-impedance, and should be resistant against vibration and corrosion. Grounding conductors on an open-air deck must be made of corrosion-protected steel, and inside the ship they must be made of copper.

The grounding should be done in such a way that the connection could be inspected in a convenient manner.

EMC Purposes

Connect only the shields of cables that are indicated in the wiring instructions. As rule of thumb, the shield of any transmit wire get grounded at the transmitting source.

Protective Ground

All removable metallic parts of the housings are grounded by means of separate, flexible cables to the main structure of the housing. It is important to connect this ground-cable after parts have been dismounted or exchanged.