Rectangular sintered bronze grounding plate from Glomex is a hull-mounted ground plate for the electrical grounding of marine electronic equipment. This Standard variant is model RA203 and measures 155 × 51 × 13 mm.
The plate creates electrical contact between the boat's ground or earth system and the water. It can be used in installations with GPS, Loran, satellite equipment, and SSB radio telephones, as well as for general generator grounding and the reduction of radio interference. The stated copper-equivalent grounding surface area is 1.5 m².
The grounding plate is made of golden, sintered bronze consisting of bronze microspheres. The porous structure allows water to penetrate the material's surface, providing an effective contact area more than ten times larger than the geometric surface of a solid plate of the same external dimensions.
The RA203 has two mounting holes with a diameter of 6.5 mm and a center distance of 68 mm. The plate is mounted externally on a flat area of the hull that is always below the waterline, oriented parallel to the boat's centerline. Avoid mounting on the transom or immediately in front of depth sounders, speed sensors, and other transducers, as turbulence behind the plate can affect them.
Use the plate as a drilling template during installation. There must be access from the inside of the hull, and the area must be checked for tanks, pipes, and cables before drilling. Underwater-rated sealant should be applied around the mounting holes from the inside, but the back of the plate itself must not be covered, as the bronze must be in contact with the water. The delivery includes 2 bronze bolts, 2 spacers, and 3 nuts.
The electrical connection is made using at least #8 AWG stranded copper wire and ring terminals. For direct connection to the battery's negative terminal, the wire must be the same size as the main negative battery cable. For HF installations using copper strapping, the strap must be at least 50 mm wide and run as directly as possible. The plate must not be painted and should be inspected annually. Cleaning can be performed with a stiff brush and bleach.
Key featuresStandard grounding plate, model RA203
Hull mounting below the waterline
155 × 51 × 13 mm
Sintered, porous bronze
Copper-equivalent grounding surface: 1.5 m²
2 mounting holes, Ø 6.5 mm
Center distance between holes: 68 mm
Mounting hardware included
For marine electronics, SSB radio, and generator grounding
Must not be painted
