Transcript Basic electric Tools and Tackles

Hand tools are tools manipulated and operated by our hands without
the use of electrical energy
Hand Tools and Their Uses
Screw Drivers
Screw drivers are made out of tools steel hardened and tempered
at the tip. They come in various size and shapes, which are used to
turn or drive screws with slotted heads
1.Standard Screwdriver.
Standard screwdrivers are used to
tighten or loosen flathead screws
2.Philips screwdriver.
Philips screwdrivers are used to
tighten or loosen Philip screws.
3.Stubby/close quarter screw driver.
The lip is similarly shaped like the
standard screw driver but with
short shank blade and shorter
handle which is made of plastic.
4.Offset Screwdriver.
Offset screwdrivers provide means
of reaching difficult flathead
screws.
Pliers
Pliers are used for cutting and twisting wires and to grip
small parts. Pliers are available with both insulated and
uninsulated handles. insulated handle pliers should be
used when working on or hot conductors
1.Slip Joint Pliers
Are used for a wide range of
service involving gripping,
turning and bending.
2.Side cutting Pliers
Appropriate for cutting cable,
removing knockouts, twisting
wire, and deburring conduit.
3.Long Nose Pliers
Appropriate for bending wire,
cutting wire, and positioning
small components
4.Diagonal Pliers
Useful for cutting cables and
wires too difficult for side
cutting pliers
5.Retainer Ring Pliers
Used to install retainer rings,
which are a type of fastener
used in assembling parts
6.Flat nose Pliers
Commonly used in sheet metal
to bend edges
Wire Stripper
Remove insulation from small
diameter wire
Electrician’s knife
Removes insulation from cable
and service conductors.
Hammers
Classified either as soft or hard faces. The cylindrical
shape head hammer has a hard face for striking hard
objects like cold chisel, star drill, and nails
1.Claw Hammer
Can be used to mount electrical boxes
and drive nails.Can also be used to
determine height of receptacle box
since most hammers are 12” in length
from head to end of handle ,or can be
so marked
2.Ball peen Hammer
Designed for striking chisels and
punches. They also may be used for
riveting,shaping,and straightening
unhardened metal.
3.Soft faced hammer (Rawhide or plastic
hammer).
Used for rewinding jobs like forming
coils, assembly and disassembly of
motors
Wrenches
Used to turn nuts or hold the pieces of stock when
tightening screws,nuts,and bolts
1.Adjustable wrench
(a). Adjustable End Wrench
It is handy and can quickly be
adjusted for size to grip/grasp
piece of stock
(b). Vise-Grip Wrench
A special wrench, which can be
locked on to an object and will grip
it with great pressure. The round
knurled knob in the end of the
handle is screwed in or out to
adjust the jaws to the size of the
object, which is to be gripped
(c). Pipe wrench
They are designed for tightening
and loosening pipes as well as for
holding round objects
2.Open-end wrench
This wrench grasps the nuts on
only two of its flat side, and is
subject to slipping under a
heavy pull.
3.Socket wrench
It is very convenient to use and
in most instances is faster to
turn or remove the object than
compared to other wrenches
4. Box wrench
It is an excellent tool as it
grips the nuts on all sides. This
reduces the chances of slipping
with resultant damage to the
nut and possible the hand.
5.Allen wrench
The end tip is shaped
hexagonally to fit the same
shape of the screw to be
tightened or loosened.
Bearing Puller
Use to pulling gears, bearings,
and bushings on the shaft of
the motor or generator.
Center Punch
Used to marking metal parts so
that they can be correctly reassembled as well as for
marking and centering on
metal part to bore holes.
Cold Chisel
Used to cut thin metal as well
as to remove little projections
of metal on smooth metal
surfaces
Hacksaw
Cuts heavy cable, pipe, and
conduit.
Pipe Burning Reamer
Used to deburr or remove
rough edges from inside cut
conduit.
Pipe cutter
Used to cut small size of pipes.
it has three small round
cutters made of hardened
steel. The pipe cutter is
slipped over the pipe where
the cut is to be made; the
cutter is then pressed against
the pipe and rotated around to
cut a groove until the pipe is
cut.
Pipe Vise
Are especially designed to hold
pipe or round stock.
Bench Vise
Used to hold pieces of stocks for
hand tool operation such as filling,
cutting, bending, tapping, threading
and reaming. All vises consist
essentially of fixed jaw, movable
jaw, screws and handle
Pipe Threader
Used to thread rigid conduit pipe at
a variety of locations on the job
site.
Hickey
Used to bend rigid conduit to a
variety of locations on the job site
Push-pull Tape Rule
Useful for rapid layout in
measurements. Should be as wide as
possible for easy extension.
Tin Snip
Used for cutting of thin sheets of metals
Test light
Is a pocket size tool used to test line
wire or circuit if there is a current in it.
File
Is made out of carbon steel with brittle
and sharp teeth, used to smoothen and
remove rough surfaces or edges of
metals. Files have different sizes and
shapes of blade with wooden handle. It
is manufactured in flat, half-round and
round file.
Soldering Gun.
The contour shape of this tool is similar
to a hand gun with hard copper wire as
soldering tip. this is used to solder
joints and terminal connections
Panel meter
A meter that measures only
one electrical quantity is
called a panel meter. The
meters may be either
analog or digital
1.Analog meters
Meters with moving pointers
are called analog meters.
2.Digital Meters
The meter movement is
replaced by an electronic
digital display.
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A meter is a measuring instrument.
An ammeter measures current,
A voltmeter measures the potential difference (voltage)
between two points, and
An ohmmeter measures resistance.
A multimeter combines these functions, and possibly some
additional ones as well, into a single instrument.
Before going in to detail about multimeter, it is important
to have a clear idea of how meters are connected into
circuits.
Diagrams in Next Slides show a circuit before and after
connecting an ammeter
Ammeter
An ammeter is an instrument
that measures electric current.
Types
1. DC Ammeter
2. AC Ammeter
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To measure current, the circuit
must be broken to allow the
ammeter to be connected in
series.
Ammeters must have a LOW
resistance .
All the current flowing in the
circuit must pass through the
ammeter.
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Select the current
function
Select a range that is
greater than the expected
current
Physically interrupt the
circuit
Observing polarity,
connect the ammeter
between the points
created by the
interruption.
Clamp meter
Clamp meter is an
instrument for measuring
of current flow in a
circuit
Volt meter
A voltmeter is an instrument that
measures voltage
Types of voltmeters
1. DC Volt meter
2. AC Volt meter
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To measure potential
difference (voltage), the
circuit is not changed: the
voltmeter is connected in
parallel .
voltmeters must have a HIGH
resistance .
The voltmeter is connected in
parallel between the two
points where the
measurement is to be made.
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Select the correct voltage function (AC or DC)
for the type of voltage used in the circuit
Select a range that is greater than expected
voltage
Determine the polarity of the voltage to be
measured by looking at the schematic diagram
or at the battery terminals (not for AC)
Connect the negative (black) lead of the
multimeter to the negative end of the voltage
to be measured. Connect the positive (red)
lead of the meter to the positive end of
voltage
Ohm meter
It is an instrument that measure
resistances. It is also used for
checking the continuity of electrical
circuits, coils of wires, heaters, etc.
When measuring or testing with an
ohmmeter, make sure the device to
be tested is free from any source.
i.e. no voltage across the device to
be tested
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To measure resistance, the
component must be removed from
the circuit altogether
Ohmmeters work by passing a small
current through the component and
measuring the voltage produced.
If we try this with the component
connected into a circuit with a power
supply, the most likely result is that
the meter will be damaged.
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Remove power from the circuit
Select an appropriate range in the ohms
function
When using, short (touch) the test leads.
Test the ohm adjust control until the pointer
reads to zero ohm
Connect or touch the test leads to the
terminals of the device whose resistance is to
be measured
Megohmmeter
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It is an ohmmeter that can measure very
high resistance
When cranked ,it generates a DC
voltage. The DC voltage is applied to
the terminals of the equipment being
tested for about one minute to test the
strength of insulation resistance
Applications
1. Test the insulation strength of wires and
cables
2. Measure the insulation resistance of
wires
3. Measure the insulation resistance
between wire to ground
In the following example of using the megohmmeter,the test is made
at the point where power leaves a motor starter
Establishing a good ground
Before the test is actually begun, it is necessary to establish a good
ground. This is done by connecting the black (negative) test lead to
ground and then grounding the red (positive) lead at another point.
cranking the meter then tests the ground connection.
If the dial moves to zero, the ground is good. This proves that the
black lead is left in position while the test is done.
Note: When the megohmmeter is being cranked, care must be taken
not to touch the test leads because of the danger of electrical
shock.
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The first step in using the meter is to test it to make sure that it
is functioning correctly
The next step is to prepare the equipment by
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De-energizing the component
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Verifying the power to the component is OFF
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Disconnecting the component from its circuit
Connect the red lead to the bundle of wires
Read the meter-Record this value
Set the range switch to the discharge position-The purpose of
the discharge position is to discharge the voltage stored uo in the
equipment from the test.
Safety Precaution: Do not disconnect the meter before the equipment
has been discharged. The voltage present before discharging creates an
electrical shock hazard
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Interpret the reading-to determine the quality of insulation
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A multimeter or a multitester is an electronic
measuring instrument that combines several
functions in one unit.
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The most basic instruments include an
ammeter, voltmeter and ohmmeter.
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Analog multimeters are sometimes referred to
as "volt-ohm-meters", abbreviated VOM.
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Digital multimeters are usually referred to as
"digital-multi-meters", abbreviated DMM.
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A multimeter can be a handheld device useful
for basic fault finding and field service work or
a bench instrument
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An analogue meter moves a needle along a
scale. Switched range analogue multimeters
are very cheap. The meter movement is
delicate and dropping the meter is likely to
damage it.
Each type of meter has its advantages. Used as
a voltmeter, a digital meter is usually better
because its resistance is much higher, 1 M ohm
or 10 M ohm , compared to 200 ohm for a
analogue multimeter on a similar range.
On the other hand, it is easier to follow a
slowly changing voltage by watching the
needle on an analogue display.
Used as an ammeter, an analogue multimeter
has a very low resistance and is very sensitive,
with scales down to 50 µA. More expensive
digital multimeters can equal or better than
this performance.
Most modern multimeters are digital and
traditional analogue types are destined to
become obsolete.
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Digital meters give an output in numbers,
usually on a liquid crystal display.
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The central knob has lots of positions.
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We must choose which one is appropriate
for the measurement you want to make.
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If the meter is switched to 20 V DC, for
example, then 20 V is the maximum
voltage which can be measured.
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This is sometimes called 20 V fsd, where
fsd is short for full scale deflection.
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Sometimes, we will want to measure
smaller voltages, and in this case, the 2 V
or 200 mV ranges are used.
Thank You