Why are Quintrex’s wired the way they are?

We are often asked why our boats are wired the way they are. The purpose of this document is to provide a clear and definitive response to that question.

When an outboard engine is connected to a battery, the outboard becomes an earth point. A continuity test with a multimeter will show this. When the outboard is bolted to a hull using stainless steel bolts, the earth passes through to the hull, albeit poorly.

When an electrical system is fitted to a boat at the factory, we provide an earth return point for a negative wire to run back to the battery from the hull. The purpose of this wire is to provide a clean path of return to the battery for the poor earth originating from the outboard engine.

Bonding Wire installed on a Quintrex

Bonding Wire installed on a Quintrex

All accessories fitted to the boat such as navigation lights or depth sounders are all grounded via our boat harness.

As you will see by conducting a continuity test with a multimeter, if this earth return point is not connected to the battery, there may be stray current in the hull. If the stray current does not have a path of return into the system via the bonding wire, it will isolate through dead spots in the hull and escape through to the ocean. This will cause issues throughout the life of the boat.

This practice has been reviewed and endorsed by third party experts in the field of corrosion consultation for recreational & commercial marine vessels.