Purchase an isolation transformer to protect your onboard radios, computers, TVs, and even vulnerable refrigerators and air conditioners, as well as underwater thru-hulls, trim tabs, propellers and shafts, from the liability of shore-side power hazards such as voltage fluctuations and spikes, reverse polarity, stray current galvanic corrosion, and more.
Installing an isolation transformer will ultimately save you a lot of money in future repair, replacement, and yard work costs, as well as providie an extra margin of safety and peace of mind regarding the integrity of your vessel's underwater gear.

Designed specifically for marine installations, Charles Isolation Transformers protect your boat from a host of AC shore power hazards by electrically separating your boat's AC power system from the AC shore power leaving the hazards on the dock, so to speak.

When an isolation transformer is installed, even when "plugged in", the boat's electrical system and grounding conductor are not actually connected to the shore-side power there is no direct electrical connection between the earth-grounded shore AC power and your onboard electrical system.
Furthermore, your boat's AC system is now isolated from all the other boats in the marina, which are otherwise all connected to each other via the dock's green grounding wire. This protects your boat from all-too-common stray current faults on neighboring vessels, and eliminates all the underwater metal corrosion consequences of being in an electrically "hot" marina.

Although more expensive, isolation transformers provide better overall value with superior,and more all-encompassing protection compared to the poorer alternative of installing a galvanic isolator - which speaks only to the green grounding wire issue, and not shore-side hazards.
They also diminish the potential for in-the-water shock hazards for swimmers and divers.

Select your isolation transformer by matching it to your vessel's electrical service. You may also want to take into account the transformer's dimensions and weight, should space be limited.
3.6 kVA and 12 kVA units mount to either bulkhead or deck. 24 kVA unit mounts to deck only.

Features:
Provides efficient, clean, and safe AC power for onboard electrical systems
Fully isolates the boat from potential electrical shore-side hazards
Eliminates the hazard of connecting to an unknown and/or foreign shore power sources
Corrects and resolves dockside AC power issues, allowing continued power to your boat's electrical system
Eliminates the need for reverse polarity sensing circuit breakers and indicators by correctly polarizing the onboard AC power which resolves reverse polarity issues
Eliminates stray current galvanic corrosion which prevents damage to through hull fittings, outdrives, drive shafts, struts, propeller and trim tabs
Eliminates the need for a galvanic isolator and status monitor
Eliminates the need for polarity alarms
Whisper quiet operation
Built in terminal block with two position options for easy wiring
Cable strain relief device (an important safety feature) is included
Ignition protected
Keyhole mounting slots for easy installation
Rugged, lightweight, corrosion-resistant powder-coated aluminum construction
Marine UL listed and approved
Meets all ABYC, NMMA, and USCG standards
European CE EMC certification (50hz models)
Designed, engineered and constructed in the USA
1-year limited warranty

Note These units need adequate air supply.


Heavy on the technical side...

The shore ground is connected to a thick, full current carrying copper shield (per ABYC) that is wound between the primary (shore) and the secondary (boat) transformer windings and which must withstand an isolation test of 4,000 volts. The connection of the grounding wire only to the shield of the transformer isolates the boat's AC system from the shore.
Fully-encapsulated components and transformer windings
Eliminates the need for AC ELCI/RCD sensing breakers
Suppresses voltage spikes and fluctuations that can damage air conditioners, refrigeration systems, computers, TVs, audio/video equipment and electronics; protecting your valuable equipment. (Transient spikes from the marina's AC power system and nearby lighting strikes can be suppressed by transformers vis the shield between the windings.)
Helps protect onboard electrical systems from interfering emissions, municipal power fluctuations, even nearby boats that have poor electrical systems which could cause radio static and TV or display screen interference.

Without a Charles Marine Isolation Transformer, your boat is electrically connected to everyone else's boat at the marina - their potentially hazardous issues could become yours as well.