Raymarine RD418HD User Manual page 17

Bonded ground system (preferred)
RF ground system (alternative)
1. Power cable to product
2. Drain (screen)
3. Bonded (preferred) or non-bonded RF ground.
4. Battery
Installation
Implementation
If several items require grounding, they may first be connected
to a single local point (e.g. within a switch panel), with this point
connected via a single, appropriately-rated conductor, to the boat's
common ground. The preferred minimum requirement for the path
to ground (bonded or non-bonded) is via a flat tinned copper braid,
with a 30 A rating (1/4 inch) or greater. If this is not possible, an
equivalent stranded wire conductor maybe used, rated as follows:
• for runs of <1 m (3 ft), use 6 mm
• for runs of >1 m (3 ft), use 8 mm
In any grounding system, always keep the length of connecting
braid or wires as short as possible.
Important: Do NOT connect this product to a positively-grounded
power system.
References
• ISO10133/13297
• BMEA code of practice
• NMEA 0400
2 (#10 AWG) or greater.
2 (#8 AWG) or greater.
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