Electrolysis and corrosion are permanent threats for your boat
Galvatest detects electrolysis before it is too late...


The only efficient way to check if anodes are working correctly and if there are no electrolytic currents on board, responsible for destroying electrolysis, is to check regularly* afloat the corrosion potential of immersed metals. In which case you run the risk of discovering possible damages only during yearly scrub-off, this means too late. Considering repair costs of a Sail-drive or aluminium hull, this simple preventive control – mandatory on all big ships – will gradually become effective for all. Galvatest offers specific cathodic protection techniques and control tools dedicated to small boats (recreational and working boats).

Galvatest Sensors

Galvatest sensors
Galvatest sensors are Ag/AgCl reference electrodes allowing, when combined with a high impedance multimeter, accurate control of corrosion susceptibility for metal hulls and all propulsion systems. They are available in several versions, according to the intended use: individual or professional.

Galvatest Controller

Galvatest controller
Galvatest leds controller is a mobile electronic device, which,  combined with its Galvatest sensor, assesses at once, and as often as necessary, cathodic protection level of a metal hull or propulsion system and eventuality of stray currents, responsible for electrolysis, real foes of your boat.

Galvatest Kits

Galvatest kits
Galvatest control and monitoring kits are autonomous complete systems intended for boaters and nautical professionals. Their regular methodic use is recommended to ensure the good "health" of any boat and guarantee the harmlessness of any servicing work on the boat's electrical circuit.

 What about the planet?

Systematically change anodes during annual lift-off is a chemical, economical and ecological non-sense. Anodes should be replaced when they stop delivering the expected protection potential. And it is not just a guess, it is a measurement…

Steel or aluminium metal hulls

metal hull are corrosion sensitive

Metal hulls made of steel or aluminium are primarily concerned by electrolysis and the regular control of their corrosion potential. Such control is conducted in "real time" on all big ships and is an integral part of formal ABYC (American Yacht and Boat Council) recommendations for all recreational boats in aluminium. Be very careful with your hanging anodes : if they are made of magnesium at sea, they will be likely to destroy your immersed paint work. 

Polyester hulls propulsion systems

propulsion systems of grp hulls are very corrosion sensitive

Unlike metal hulls, polyester hulls (GRP) do not carry electricity. Thus, propulsion systems S- or Z-drives are particularly concerned by Galvatest control. Their carters are made of very conductive aluminium which stands as a primary route for on board or ashore stray currents seaking to travel through the sea... And this is also true for propeller shafts on such hulls.

They did not die all, but all were struck!

all were struck

40 mA received during 30 days will definitely destroy 10 g of aluminium... And because it is a natural phenomenon, your boat did have, have or will have corrosion problems! Don't wait, act now! Consequences of corrosion – often costly – are never covered by insurance companies. Have a look at simulated consequences of a 1 A current leak received through an aluminium sail-drive during 100 days, page Demonstrations.

Use of Galvatest is recommended by major

Regular control of metal hulls and immersed equipments corrosion potential is a recommended practice of international standards and major boat and equipment manufacturers. All our electrodes sensors are individually tested. Patented technology. Galvatest is a member of F2N: Filière Nautique Normande.

www.galvatest.fr en français


Galvatest en français...


The original comic strip "How goes your boat?"

To understand quickly and without painful headache, download our explanatory comic strip. You will learn, with just a few pictures, how to use Galvatest to assess instantly cathodic protection level given by anodes, and if harmful stray currents are eating your boat.

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The White Paper about cathodic protection...

WP Galvatest cathodic protection

With White Paper about cathodic protection published by Galvatest, you will learn all you ought (or wish) to know about galvanic and electrolytic corrosion phenomenons affecting small recreational or working boats.

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What certification bodies say...



 Downloadable documents

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