Regal 3300 Owner's Manual page 209

Only use a shore power cord that is in excellent condition with
no cuts, nicks or abrasions in the exterior plastic cover. The
cord must be specifically designed to connect the yacht to a
shore power source. Tlectrical shock that could result in death
or serious injury can occur by using a damaged shore power
cord or a cord that is not designed for the intended purpose.
Never allow the end of the shore power cord to hang in the
water. An electrical field may exist that could cause death or
serious injury to nearby swimmers.
Electronic Leakage Circuit Interrupter
(ELCI)
The ELCI is installed near the boat's shore power connector inlet and
provides whole boat protection for everything downstream of it. AC
outlets are further protected with marine-grade Ground Fault Circuit
Interrupters (GFCI) for protection in potentially wet environments.
It is important that the ELCI is working properly to provide protection
against electric shock. It should be tested at least once each month to
ensure proper operation by pressing the TEST/ RESET buttons in
the faceplate. Refer the ELCI manufacturer's instructions for testing
details and fault codes.
https://www.boat-manuals.com/
!
WARNING
On boats with shore power,
the AC electrical system is
a l s o e q u i p p e d w i t h a n
Electronic Leakage Circuit
Interrupter (ELCI) which will
open (trip) under dangerous
conditions. This situation can
o c c u r w h e n t h e r e i s a
combination of a ground
fault, and, a faulty ground,
and is a hazard to both people
in the boat and in the water.
Features
6-49