4
Theory of operation-
Why you need a ProSafe Isolation Transformer
When properly installed and connected, the ProSafe Isolation Transformer will provide isolation
between shore and boat power while maintaining a one to one turns ratio, meaning the shore
voltage is equal to boat voltage.
This is a high quality product, however, it is possible to unknowingly abuse or
misapply a transformer, therefore reducing its life expectancy. These installation and operation
instructions set out the guidelines for peak performance of the ProSafe Isolation Transformer.
The information contained in this manual outlines for the user the proper inspection, installation
and maintenance required of these transformers.
With the ProSafe Isolation Transformer, a boat’s electrical system and common grounding
conductor are not connected to the shore-side system. Power is transferred from the shore-side
electrical system to the boat’s electrical system by magnetic coupling. Specifically, this means
there is no direct electrical connection between the shore-side, earth-grounded AC power and
the boat’s AC power systems. The shore grounding is connected to a shield that is placed
between the primary (shore) and secondary (boat) transformer windings. This shield ensures
isolation of the boat because of its placement between the primary and secondary windings
within the transformer. In the unlikely but possible event a breakdown occurs within the ProSafe
Isolation Transformer, the shield can bear the fault current of a properly sized shore supply
circuit breaker long enough for the breaker to trip.
Properly installed, the ProSafe Isolation Transformer will electrically isolate AC shore power
from the boat’s AC power system, reducing galvanic corrosion due to a direct AC shore power
connection. This occurs because grounding one leg of the transformer secondary on board the
boat results in the establishment of a “neutral” ground. When the ProSafe Isolation Transformer
is properly installed, shoreline polarity is no longer a concern and the use of a galvanic isolator
is not needed.
Additionally, ProSafe Isolation Transformers are engineered to supply superior line noise
reduction and spike suppression, providing high quality AC power from less than perfect power
sources.
TRANSFORMER DESIGN FOR SOUND REDUCTION
ProSafe Isolation Transformers are “sound-controlled” in construction so that sound levels
consistent with industry standards are achieved. Transformer coils are precision wound under
measured constant tension to insure continual, vibration-free performance. Low noise levels in
the core are maintained by using specially designed clamps for bolting the core into a tight
unified assembly. All clamping bolts are tightened to an optimum torque level. Additional sound
reduction is realized by impregnation with polymerizing varnish cured by a special baking
process. Cabinet styles have their core and coils mounted to the cabinet on neoprene pads for
reduction of conducted sound. The case is formed and assembled using dampening agents to
reduce transmitted sound. The result is ultra quiet operation for the user.
