Download Session 810

ELECTRICAL TESTING
FOR SURVEYORS
• IBEX 2013, Session 810
• Presented by: Dwight Escalera, Executive
Marine Services and
• Ed Sherman, ABYC
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NEED FOR
ELECTRICAL
TESTING
• Several years back, insurance
data told us that 55% of all
boat fires were caused by the
electrical system faults
• So, today we’ll look at what
we consider basic tests to
verify the safe condition of an
electrical system
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WHAT IS REQUIRED BY THE
SURVEYOR?
• Basic understanding of electrical systems
• Provide basic meters to check electrical
systems
• Include basic tests in all surveys
• Document results and recommendations
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BEFORE GETTING STARTED, CONFIRM A FEW THINGS AND
BE SAFETY CONSCIOUS….UNLIKE SOME BOAT OWNERS….
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SAFETY CONCERNS WHEN CHECKING
ELECTRICAL SYSTEMS….
• Is the vessel connected to shore power?
• Even if unplugged, it could have an inverter that
could get knocked out of sleep mode. Check for
this and shut down that system.
• Vessels on land and connected to power can be
lethal.
• Assume that a problem exists.
• Make no assumptions about wire color coding
and a circuit’s function.
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ADDITIONAL
SAFETY
POINTS:
• Be especially careful around inverter
chargers, AC equipment and water
heaters, the case could be live, and you
could end up as the path to ground.
• Test for this with your multimeter
connected between a known good
ground and the case with the meter set
to AC volts, if you get a voltage reading,
look out!
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COMMON METERS
• Multi-Meter (DVOM)
• Ideal Sure-Test
• Clamp-on Ammeter
• Conductance Battery Tester
• Pyrometer (non-contact thermometer)
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DVOM
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•
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Test Fuel system ground resistance
Test Galvanic isolator
Method of operation
Common tests:
Charging System Output
AC Ripple Test
Engine Cranking Voltage
DC Ground Leaks
False Grounds (neutral to ground links on
board)
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IDEAL SURE TEST METER
• Method of operation
• Common tests
• Let’s look at the entire sequence
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FIRST SURE TEST
• Basic System Connections are
being tested in this photo.
• The possibilities are shown on the
back of the tool and shown here:
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SECOND SURE
TEST
• True RMS Line Voltage
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THIRD SURE TEST
Neutral to Ground Leakage,
Hot to Neutral Leakage
Typically caused by poor insulation or
maybe a salt bridge at terminals. Less
than 2 VAC considered acceptable.
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THIRD SURE TEST
Peak AC Voltage
1.414 times measure of
true RMS line voltage
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FOURTH
SURE
TEST
System Frequency can be
verified
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FIFTH SURE TEST
Voltage drop can be measured at
different amperage levels. This
should be tested at all on board
receptacles. The most acceptable is
10%
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SIXTH SURE TEST
Available short circuit current can be
verified. There is a correlation
between this value and appropriate
wire sizing and terminal integrity.
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SEVENTH, EIGHTH, NINTH
AND TENTH SURE TESTS
The Sure Test will also measure the ohms of
electrical resistance in the hot, neutral and
grounding conductors. Finally, it will
measure trip current and trip time for GFCI’s
and GFP devices. These values equate to
establishing wiring and connection integrity
as well as effectiveness for ground fault
protection devices.
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CONDUCTANCE BATTERY
TESTER
• Method of operation
• Common tests include:
• Battery integrity and
life expectancy.
• Charging system tests
• Starter system tests
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PYROMETER
•
•
•
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Heat equals electrical resistance………
Common tests:
Hot components
Bad Electrical connections
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CLAMP-ON AMMETER (AC
LEAKAGE)
• Method of operation
• Common tests
• Searching for AC
ground faults.
• Process of elimination
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ARE THERE ANY FURTHER
QUESTIONS?
Thank you for your interest!
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