Professional BoatBuilder - February-March 2018

76 PROFESSIONAL BOATBUILDER

PARTING

SHOT

W

ith the introduction of ground

fault protection (GFP) technol-

ogy to boats and docks, equipment

issues are beginning to surface. Some

new tactics, techniques, and proce-

dures (TTP) will be required to sort

out and resolve them.

A few years ago, the American Boat &

Yacht Council (ABYC) introduced a

requirement to provide whole-boat

ground fault detection in the form of an

ELCI (equipment leakage circuit inter-

rupter). is device is designed to trip if

there is 30-mA (milliampere) or more

AC leakage from the boat’s electrical sys-

tem. e National Fire Protection Asso-

ciation (NFPA) followed suit in 2011

with a requirement for ground fault pro-

tection on overcurrent protection

devices used for powering boats. e

NFPA trip level was initially 100 mA

max but was lowered to 30 mA max in

2017. ese two ground fault initiatives
      have signicantly improved safety in the
      marine environment.
      e complicating downside is that
      aging electrical equipment begins to
      leak AC current into the ground system.
      is is most prevalent with motor loads
      (like air-conditioning compressors) but
      is also common on water heaters and
      other loads that depend on good insula-
      tion between energized components and
      ground. Prior to ground fault protection
      requirements, these devices would con-
      tinue to deteriorate unchecked, resulting
      in AC leakage currents that led to dan-
      gers including electric shock in and out
      of the water, and re hazards from heat
      generated at electrical faults. Because
      ELCIs are relatively new, so too are
      most boats equipped with them. Conse-
      quently, most of these boats have not yet
      suered from the electrical system dete-
      rioration that comes with time.
      Since tripping of an ELCI severs all
      power to the boat, it quickly gets the
      owner’s attention. Today’s growing issue
      is how to sort out an ELCI trip: What
      equipment caused it? Was it caused by

multiple pieces of equipment each con-

tributing a small amount to the total

leakage? How is this diagnosed and

resolved? ankfully, we have some time

to develop TTP for these newer boats.

e ground fault leakage problem

becomes more acute with the addition of

ground fault protection on docks, which

may include protection at each pedestal

receptacle, and/or protection at feeder

breakers powering multiple pedestals.

Boats of all vintages are now plugging

into these ground-fault-protected elec-

trical systems, and breakers are tripping

as a result of AC current leakage from

these boats. So how does a marine elec-

trical technician determine the cause of

the pedestal breaker tripping? And how

will the owner react to, “Sir, you have to

replace your HVAC system due to elec-

trical leakage”? Most likely: “But my

HVAC is still blowing very cold air and

has been for 15 years.” How is the indus-

try going to handle this?

Consider this scenario: An owner

turns on his air-conditioning and the

boat’s ELCI (or pedestal receptacle

breaker) trips. is happens frequently,

so he reports it to his marine service cen-

ter. e electrician determines the A/C

unit likely has a ground fault causing the

tripping, but he/she doesn’t know how to

test the A/C since it keeps tripping the

boat’s main ELCI breaker, turning it o.

(See Rovings in Professional BoatBuilder

No. 164 for information about a Blue Sea

ELCI testing tool.) So the owner replaces

the HVAC compressor at considerable

cost. All appears to be ne. But what if

the HVAC unit was contributing only a

few milli amps of leakage to the total boat

leakage—just enough to get that total leak-

age higher than the 30-mA trip level?

Maybe the water heater was leaking 29

mA all along, and when the A/C added

its own few milliamps, the protective

action occurred. Which straw broke the

camel’s back?

e solution has two parts. e rst is

developing new TTP, and then training

marine electrical technicians to use

them. is is no longer advanced-level

stu; it must be part of basic electrical

training. In my opinion, every marine

electrician should possess the skills to

tackle this new area of marine electri-

cal troubleshooting and repair. While

the science is settled, TTP is still open

for new ideas and innovative thought,

which should include ideas from indus-

try professionals, including ELCI/GFP

manufacturers.

e second part is more cultural, and

will be a complex public relations and

consumer education issue. When the

HVAC is blowing cold air, why should an

owner invest thousands simply because of

some electrical leakage? e answer is

that, though usually undetectable through

the human senses, electrical leakage can

be very dangerous, with the potential to

cause re, injury, and even death. is,

too, is settled science, but when people get

disgruntled, they are more inclined to dis-

engage from the activity altogether, rather

than pouring money into something they

don’t understand.

is is a call to the industry to recog-

nize that the “ground fault train” has le

the station and is arriving at many loca-

tions around the country. A new set of

best-practice protocols must be devel-

oped to handle this new area of mainte-

nance and repair. Marine electrical tech-

nicians need training as soon as possible

(including supplemental training for

those already certied in the trade). In

addition, a clear warning about the dan-

gers of operating equipment with electri-

cal leakage should be woven into the

boating culture, present and future. With

some creative thought, training, and stra-

tegic messaging, we can keep the train

safely on the tracks.

About the Author: Retired U.S. Navy cap-

tain David Riin is a marine corrosion/

electrical consultant, and a former instruc-

tor in corrosion and electrical certication

for the American Boat & Yacht Council.

Ground Fault Detection:

Avoiding a Train Wreck

by David Riin

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