We are in the process or installing "dual" marine Puck Isolation transformers behind the main salon TV/Power cabinet, replacing our "factory installed" ProMarine Zinc saver.\

https://www.bridgeportmagnetics.com/bmg ... nsformers/

Marine-Pucks are toroidal (ring shaped) isolation transformers fully embedded in solid epoxy resin inside a cup-shaped non-metallic enclosure. They are sealed hermetically and can be mounted onto a deck or a bulkhead.

There are many advantages of toroidal transformers versus conventional laminated types.
They are up to 50% lighter and much smaller.
They are quiet. No annoying hum when on shore power.
Marine-Pucks are double-insulated (class II devices) not referenced to ground in any way.
They can be adapted to boost output voltage to compensate for drops and fluctuations caused by long dock-runs or in marinas with 208V rather than normal 240V service.
Marine-Puck are available in standard and automatic boost models (B suffix).
B models automatically select boost in case of low input voltage. They include a separate control unit with a non-metallic enclosure measuring 5” x 5” x 7”. Weight 4 lbs.