Module 2
Electrical Equipment, Schematics and Safety
Ship's Lighting
System
• Marine lights are referred to as a general name
of illuminated ship lights. The boat light can not
only be used for lighting and navigation but
also be applied for signal transmission.
• Marine navigation signal lights,
• Anchor lights,
• Head lights
• Marine ceiling lights,
Types of
Marine
Illumination
or Lighting
• Marine dome lights
• Emergency lights
• Flashing signal lights
• Solar navigation signal lights,
• Chart lights
• Morse signal lights
• Daylight signal light
• Marine fluorescent pendant
• Portable lights
• Marine spot light,
• Marine flood lights,
• Marine search lights,etc.
Importance of Ship's Lighting System
• The primary function of marine navigation lights is to
aid prevention of any major accident from happening.
• The color of the lights that were required to be used as
specified by a set of rules passed in the UK. On the
basis of this rule, three colours were chosen: red, green
and white. Even today, the marine navigation lighting
consists of these three colours.
What is Electrical
Maintenance?
• Electrical maintenance is the process of inspecting,
testing, and maintaining the electrical systems in the
workplace.
• This includes the
o wiring
o the circuit breakers,
o the lighting,
o the outlets,
o and the electrical appliances. etc
The maintenance goal is to ensure these systems’
safety and reliability.
Best Practices in Electrical Maintenance
• When conducting electrical maintenance,
the following best practices should be
followed:
•
Inspect the wiring and the circuit breakers for any signs of damage or wear;
replace the parts if necessary.
•
Test the electrical appliances to make sure they are working correctly.
•
Make sure the power plugs and the cables are in good condition.
•
Check the lighting fixtures for any signs of damage and the wiring connections.
•
Clean the outlets and the light switches to remove the dust and dirt.
•
Make sure the outlets and the switches are working correctly.
•
Check the ground wire to make sure the system is grounded properly.
•
Look for the signs of rodents, insects, and water damage.
•
Make sure the system is up-to-date with the safety codes and regulations.
•
Keep records of electrical maintenance.
•
Document the changes and the repairs that are made.
•
Make the necessary repairs and modifications.
•
Test the system once the maintenance is done.
•
Use Proper Safety Equipment
Always wear the proper safety equipment when conducting electrical maintenance. This includes rubber
gloves, a hard hat, protective shoes, and eye protection.
•
Tips for a
Successful
Electrical
Maintenance
Properly Label the Wiring
Label the wiring properly to make maintenance easier and the system more efficient. It is the job of the
electrician to do the labeling. In addition, the labels should also be visible and readable. In addition, the
labels should also be updated regularly.
•
Beware of Standing Water
Standing water can be hazardous in bathrooms, kitchens, and laundry rooms. So make sure the outlets are
above the level of the water. That way, the risk of the electric shock is minimized.
•
Inspect the Electrical Equipment for Damage:
Make sure the electrical equipment is inspected for wear and damage. This includes the circuit breakers, the
outlets, the wiring, the lighting fixtures, and the appliances. By doing the inspection, the electrician can
identify the potential problems and the hazards before they become bigger.
•
Schedule the Maintenance Regularly
Regular maintenance is the key to a safe and reliable electrical system. So make sure regular maintenance is
scheduled. This includes the inspection, testing, and maintenance of the system. If the maintenance is not
done regularly, the risk of electrical shock and other hazards increases significantly.
First thing to do:
Identify which Lights Are Out
First you should identify the extent of the problem. How many lights are out? Is it
just one fitting, is it just part of the ship or are there no lights working anywhere
at all?
Common
Lighting
Faults
Lamps
If only one light is out, the first thing to check is the lamps.
Reset The Circuit Breaker
If all your lights are out and you can’t identify an obviously faulty fitting, turn off all
lights in the house and then try resetting the circuit breaker or reloading the fuse.
Water Damage
Water in an outside light fitting is a common source of problems, especially if you
have an earth-leakage circuit breaker (safety switch) protecting the circuit.
Heat Damage
Lamps with a screw-in type base can sometimes get stuck in the threaded lamp
holder and when trying to screw them out you can actually be spinning the
whole lamp holder and twisting the wires around behind it.
Old Wiring
Old rubber cable with crumbling insulation could also cause similar problems.
Presentation of
Sample Electrical
Diagram for
Lighting and Tips
for Fault Finding
Electric Motors
Main Part Of
Electric
Motor
Construction of an Electric
Motor
• Two mechanical components of electric motors
are the stator, which is fixed and the rotor, which
moves.
• It also has two electrical components, magnets
set and an armature, one of them is attached to
the stator and the other to the rotor, together
making a magnetic circuit.
Electric Motor
Bearings
• Bearings support the rotor and
allow the rotor to spin on its axis.
The motor housing in turn
supports the bearings.
Electric Motor
Rotor
• The rotor is the mobile part
that supplies the mechanical
power. The rotor generally
holds conductors which carry
current and the stator
magnetic field applies a force
on to spin the shaft.
Alternatively, other rotors
have permanent magnets, and
conductors are held by the
stator. Permanent magnets
give high efficiency over a
bigger power range and
working speed.
Electric Motor
Stator
• The stator surrounds the rotor,
and generally holds the field
magnets, these are either
electromagnets consisting of
wound wire on a ferromagnetic
core of iron or permanent
magnets. These produce a
magnetic field that passes through
the rotor winding, applying force
on the winding. The stator iron
core is made of many thin metallic
sheets which have insulation from
each other, known as laminations.
Electric Motor
Armature
• The armature comprises wound wire
on a ferromagnetic core. Current
flowing through wire makes the
magnetic field exert a Lorentz force
onto it, rotating the rotor, which
supplies the mechanical output.
Windings are wires which are applied
in coils, generally wrapped around a
soft, laminated, iron, ferromagnetic
core to produce magnetic poles when
supplied with current.
Electric Motor
Commutator
• A commutator is a rotary electric
switch which supplies alternating
or direct current to the rotor. It
periodically reverses the current
flow in the rotor winding as the
shaft spins. It comprises a cylinder
made of multiple metal contact
sections on the armature.
Electrical contacts named
"brushes" consisted of a soft
conductor material like carbon
pressed onto the commutator.
The brushes create sliding
contacts with consecutive
commutator sections as it spins,
offering current onto the rotor.
Motor Preventative
Maintenance
• A well-planned electric motor preventive
maintenance programme is the key to
dependable, long-life operation of electric
motors.
• Almost all electrical equipment requires
planned inspection and maintenance
being carrying out. This ensures electrical
equipment is kept in good working
condition at all times. Periodic
inspections prevent serious damage to
machinery by locating potential problems.
Motor Preventative Maintenance
Electric motor maintenance programmes aim to prevent critical breakdowns rather than
repairing them. In plant operations, unscheduled stoppage of production or long repair
shutdowns are intolerable. The resultant downtime eats deeply into production times.
Periodic inspections of motors are necessary to ensure best operating results.
Preventative maintenance programmes require detailed checks, and all motors onsite should
be given an ID number and have a record log. The motor records should identify the motor,
brand, inspection dates and descriptions of repairs. By keeping records, the cause of any
breakdowns can determine the fault and reduce on-going problems.
Note: All maintenance programmes should refer to the manufacturer’s techincal
documentation prior to performing checks.
Frequent checks
• 1. Clean motor of any dust or oil.
• 2. Check oil rings turn with shaft.
• 3. Check oil level in bearings.
• 4. Visually check for oil and grease from
bearings.
Every 6
months
•
1. Clean motor, blowing out dirt from windings, and wipe
commutator and brushes.
•
2. Visually inspect commutator clamping ring.
•
3. Check and replace brushes that are more than half worn.
•
4. Examine brush holders, and clean them if dirty.
•
5. Check brush pressure and position.
•
6. Remove, clean out, and replace oil in sleeve bearings.
•
7. Check grease in ball or roller bearings.
•
8. Check operating speed or speeds.
•
9. Technician to examine and tighten loose connections.
•
10. Test current input and compare it with normal.
•
11. Visually check drive, for smooth running, absence of
vibration.
•
12. Check motor foot bolts.
Annually
1. Remove and renew grease in ball or roller
bearing.
2. Test insulation.
3. Clean out magnetic dirt that may be
attached to poles.
4. Check clearance between shaft and
journal boxes of sleeve bearing motors.
5. Check the commutator for smoothness
and slot damage.
6. Examine connections of commutator and
armature coils.
7. Inspect armature bands.
Most Basic Electrical Measuring Devices
for Electrical Motor Maintenance
• Multi - Meter
Most Basic Electrical
Measuring Devices for
Electrical Motor
Maintenance
Insulation Resistance Tester
Most Basic Electrical Measuring
Devices for Electrical Motor Maintenance
• Clamp Meter
Most
Basic Electrical Measuring
Devices for Electrical
Motor Maintenance
Vibration Meter
Most Basic Electrical Meas
uring Devices for Electrical
Motor Maintenance
• Thermography Camera
Common
Causes of
Motor Failure
Voltage
imbalance
• Imbalance creates excessive
current flow in one or more
phases that then increases
operating temperatures–
leading to insulation
breakdown
Operational overloads
•
Motor overload occurs when a motor is
under excessive load. The primary
symptoms that accompany a motor
overload are excessive current draw,
insufficient torque and overheating.
Excessive motor heat is a major cause of
motor failure. In the case of an
overloaded motor individual motor
components including bearings, motor
windings, and other components may be
working fine, but the motor will continue
to run hot.
•
Premature wear on motor electrical and
mechanical components leading to
permanent failure
Misalignment
• Misalignment occurs when the motor drive shaft is
not in correct alignment with the load, or the
component that couples the motor to the load is
misaligned.
•
Angular misalignment: shaft centerlines intersect
but are not parallel
•
Parallel misalignment: shaft centerlines are parallel
but not concentric
•
Compound misalignment: a combination of parallel
and angular misalignment. (Note: almost all
misalignment is compound misalignment, but
practitioners talk about misalignment as the two
separate types because it is easier to correct a
misalignment by addressing the angular and
parallel components separately.)
• Impact: Premature wear in mechanical drive
components that leads to premature failures
Shaft imbalance
•
Imbalance is a condition of a rotating part where the
center of mass does not lie on the axis of rotation. In
other words, there is a “heavy spot” somewhere on the
rotor.
•
you can identify when it is out of normal range and act
to rectify the problem. Imbalance can be caused by
numerous factors, including:
•
Dirt accumulation
•
Missing balance weights
•
Manufacturing variations
•
Uneven mass in motor windings and other wearrelated factors.
•
A vibration tester or analyzer can help you determine
whether a rotating machine is in balance.
Shaft looseness
• Misalignment occurs when the motor drive shaft is not in correct alignment
with the load, or the component that couples the motor to the load is
misaligned.
•
In addition, misalignment may feed vibration into both the load and the
motor drive shaft. There a few types of misalignment:
• Rotating looseness is caused by excessive clearance between rotating
and stationary elements of the machine, such as in a bearing.
• Non-rotating looseness happens between two normally stationary parts,
such as a foot and a foundation, or a bearing housing and a machine.
Bearing wear
•
A failed bearing has increased drag,
emits more heat, and has lower
efficiency because of a mechanical,
lubrication, or wear problem. Bearing
failure can be caused by several things:
•
A heavier load than designed for
•
Inadequate or incorrect lubrication
•
Ineffective bearing sealing
•
Shaft misalignment
•
Incorrect fit
•
Normal wear
•
Induced shaft voltages
Improper installation
factors
Soft foot
•
Soft foot refers to a condition in which the
mounting feet of a motor or driven component
are not even, or the mounting surface upon
which the mounting feet sit is not even. This
condition can create a frustrating situation in
which tightening the mounting bolts on the feet
introduces new strains and misalignment. Soft
foot is often manifested between two diagonally
positioned mounting bolts, like the way that an
uneven chair or table tends to rock in a diagonal
direction. There are two kinds of soft foot:
•
Parallel soft foot—parallel soft foot occurs when
one of the mounting feet sits higher than the
other three
•
Angular soft foot—angular soft foot occurs when
one of the mounting feet is not parallel or
“normal” to the mounting surface.
SAMPLE MOTOR
CONTROLS
• WIRING DIAGRAM
Cathodic
Protection
Systems or ICCP
• Ships are often exposed to very harsh
marine environments. Due to the
environment in which they operate, the
ship’s hull is often vulnerable to
environmental corrosion.
• The corrosivity of seawater in regards to
general corrosion on steel increases with
increasing temperature, oxygen content,
water velocity, the content of corrosive
contaminants, eroding particles, and
conductivity. The seawater containing
salt forms a perfect electrolyte with
the ship’s hull, fully made up of iron (mild
steel), to form a galvanic cell.
Video Presentation on
Ship's ICCP
Fire Detection System
• Fire is a disaster that can cause serious damage and loss
of life and property in the place where it occurs.
Especially if this place is a ship, early detection and
extinguishing of fire is critical for life and property safety.
• Ensuring safety in ships, not just fire, is an international
issue that concerns countries. The basic security
standards of the ships were determined in the SOLAS
contract, which was published in line with this target and
which 162 countries are parties to. In the section II-2 of
the SOLAS contract, which deals with many issues from
the construction of the ships to its communication, from
navigation to cargo transportation, there are items
related to fire protection, fire detection and
extinguishing.
Types of Fire Detection System Onboard
ACCOMODATION AND ECR
SMOKE AND FLAME DETECTION
CARGO HOLD SMOKE
DETECTION (CONTAINER SHIP)
Fire Detection Accessories
Fire Main Panel and Repeaters
Control/Repeater panel for cargo. It has a 4.3" graphical colour
display used to manage and supervise the system. Mounts on
any flat surface independent from a fire alarm cabinet.
Fire Detection Accessories
Smoke Detector
A smoke detector is an electronic fire-protection device that
automatically senses the presence of smoke, as a key indication
of fire, and sounds a warning to building occupants.
Types of Smoke Detector
1. Conventional type
2. Addressable Type
Fire Detection Accessories
Flame detectors
A flame detector is a type of sensor that can detect and
respond to the presence of a flame. These detectors have
the ability to identify smokeless liquid and smoke that can
create open fire. For example, in boiler furnaces flame
detectors are widely used, as a flame detector can detect
heat, smoke, and fire. These devices can also detect fire
according to the air temperature and air movement. The
flame detectors use Ultraviolet (UV) or Infra-Red (IR)
technology to identify flames meaning they can alert to
flames in less than a second. The flame detector would
respond to the detection of a flame according to its
installation, it could for example sound an alarm, deactivate
the fuel line, or even activate a fire suppression system.
Fire Detection Accessories
Heat Detector
A smoke detector is an electronic fire-protection device that
automatically senses the presence of smoke, as a key indication
of fire, and sounds a warning to building occupants.
Familiarization of Fire
System Loops, Zones,
Test Mode,
Disablement,Isolation
of Zone, Replacing
Detectors
(Consilium Maker)
2 Types of Fire Detection System
• Conventional
• Addresable
Presentation of
Sample Wiring
Diagram of Fire
Alarm System
(Consilium)
Most Common Fault in Fire Detection System
• Fuse Fault
• Battery Fault
• Power Failure
• Earth Fault
• Sensor Fault
• Cable Break
• Short Circuit Fault
• Open Circuit Fault