Both models of isolator will work on any voltage worldwide & on 50 & 60 hz (cycles.) They are suitable for use with 3 to 63 amp shore power / onboard mcb & rcd’ breakers
I keep my boat in fresh water: do I still need an isolator?
Yes: The rate of galvanic flow increases with shorepower connection & is increased even more in salt & warm water. Fresh water still contains minerals which conduct the destructive currents creating corrosion.
How quickly can corrosion occur?
This depends on so many conditions!..type of water/ proximity of other vessels/temperature/mineral content /area of metals /type of metals.We know of a grp cruiser who suffered £6000 damage in 8 weeks due to a defective shorepower supply: an isolator would have prevented this!
You supply 2 models of isolator : What is the difference?
The model Gi70 is a standard 70 amp isolator & will control all dc galvanic problems below 1.2 volts. (Most galvanic currents are below 1.2 volts). The model GI 70sm is an advanced 70 amp isolator with a remote fault indicator. It controls all galvanic problems up to 2.4 volts thus offering extra protection in addition to which the status monitor will indicate any problems present. It also identifies whether the fault condition is a D.C. or A.C fault condition. It will protect against both "Galvanic" & "Stray" currents.
What is the difference between "Galvanic" & "Stray" current?
Galvanic currents are currents set up due to differing voltage potentials present on metals such as props / shafts/ anodes / skin fittings etc between boats /pontoons etc They are the currents which flow from boat to boat or from boat to pontoons etc. The current flow increases rapidly when you connect to shore power. Stray currents are highly destructive currents which flow from leaky shore power supplies /defective a.c. or d.c. wiring, leaky bilge switches etc resulting in increased voltages finding their way to the metalware of your boat: This is a far more serious & destructive current than pure galvanic current & is the one that does serious damage in very short periods of time . Our Gi 70 sm isolator informs you of this type of leakage thus saving serious damage!
What does the remote monitor do?
The status monitor constantly watches for any current flowing through the "green" earth wire. If a fault occurs a warning led indicates fault
Why does the monitor have 2 l..e.d's?
The monitor indicates both d.c. leakage (indicating a fault on board the vessel) & a.c. mains leakage (indicating faulty shorepower or defective vessel mains leakage condition) One l.e.d .illuminates when d.c. fault condition is present : Both l.e.d’s will illuminate when A.C. fault conditions exist.
I have 2 mains inlet sockets on board the boat : Do I need 2 isolators?
Not necessarily ; If the 2 earth wires are bonded together then 1 isolator is sufficient. If the supplies are designed to be individually earthed then 2 isolators are recommended.
How can I test the isolator? : Do I need to disconnect it to test?
You do not need to disconnect to test. Simply check the isolator with a digital meter on the ohms or diode check scale : The readings should be approximately the same in both directions.We supply full instructions for installation & testing for both our isolators. They can be fitted easily by competent d.i.y. persons We also have a helpline which does just that! A word of warning however! Some budget digital meters have an internal battery of 1.5 volts . These meters are unable to give accurate readings when testing galvanic isolators . Meters containing 9 volt internal batteries have the ability to "turn on " the internal diodes of the isolator & give accurate, reliable readings. Good quality meters are now available for under £15.00(check they have 9 volt internal battery) & are an essential accessory on board!
I have read that my neighbours boat can eat away my zincs! Is this true?
Yes it is! Something most boat owners don't realise : The fact that you make a connection to your neighbour’s boat via the earth wire means that when his zincs are gone he has a perfect path to use yours!
I am never going to connect to shorepower : do you recommend fitting an isolator?
Well we're honest & the answer is no. Galvanic currents will still flow but at a slower rate: you will not benefit from an isolator.
How long does an isolator last?
They are virtually indestructible & solid state construction epoxy sealed to prevent moisture & anodised heatsinks/stainless steel fastenings.You can easily remove & refit in your new boat : After all: Your boat wont suffer corrosion & will hold its value when the surveyor calls!
My boat is fitted with outdrives : Can they corrode?
Unfortunately aluminium can corrode at an alarming rate accelerated by shore power connection.
I am worried about electrical safety if I "break into" the green earth wire. Will my safety trips still work
Rcd / mcb shore power safety trips both on board vessel & on the shore power distribution work as normal.
What is the difference between a galvanic isolator & an isolation transformer?
They are different ways of doing the same job. They will both control corrosion but a transformer is heavy & expensive. It will not inform you of potential problems.