Preparing and Interpreting Technical Drawing
Technical Drawing or Drafting is the act and discipline of composing drawings
that visually communicate how something functions or constructed.
Technical drawing is essential for communicating ideas in industry and
engineering.
To make the drawing easier to understand, people use familiar symbols,
perspective units of measurement, notation system, visual styles, and page
layout.
Together, such conventions and constitute a visual language and help to ensure
that the drawing is unambiguous and relatively easy to understand. Many of the
symbols and principles of technical drawing are codified in international standard
called ISO 128.
The need for precise communication in the preparation of functional documents
distinguishes technical drawing from the expensive drawing of the visual art.
Artistic drawings are subjectively interpreted their meanings are multiply
determined. Technical drawing is understood to have one meaning.
A drafter, draftsperson, or draughtsman is a person who makes a drawing
(Technical or Expensive).
A professional drafter who makes technical drawings is sometimes called a
drafting technician.
Terminating and connecting electrical wiring and electronics
circuit
VOLTAGE
The measure of the push of each electron, which make the electron move
CURRENT
The flow of electronic in the circuit
RESISTANCE
The opposition to current flow
POWER
The rate of doing wok
RESISTOR
A device design internationally to have a definite amount f resistance
CAPACITOR
A device that store electrical energy
TERMINATION
The point where a line, channel or circuit end
OHS
Occupational Health and Safety
AC/DC source
Equipment that will operate on either an AC or DC power source
Battery- A dc Voltage source containing two or more cells that convert
chemical energy to electrical energy.
Cell- single unit used to convert chemical energy into DC electrical Voltage
FUSE
Fuse is a safety device used to protect electrical circuit from the effect of
excessive current. Its essential components are usually a strip of metal that
will melt at a given temperature.
A fuse is usually rated in Amperes, which represent the maximum continuous
current it could handle without blowing.
The most popular type of fuse in electronic is 3AG type.
Wires and Cables
A wire is a single slender rod or filament of drawn metal. This definition
restricts the term to what would ordinarily be understood as a solid wires
Conductor
Is a wire suitable for carrying an electronic current?
A stranded conductor-is a conductor composed of a group of wire or any
combination of a group of wires.
A cable is either a stranded conductor (single conductor cable) or a
combination of conductors insulated from one another (multiple conductor
cable)
Switch and its function
Switch is a device used to break electric current or transfer it to another
conductor.
A switch is a mechanical device used to connect and disconnect a circuit at
will.
A switch is manually operated device capable of making, breaking, or
changing the connection in electronic or electrical circuits.
Switch function
When the switch is closed, the electrons finds an interrupted path in the
circuit
Open is the OFF position of the switch, while close is the ON position
When the switch is opened, the current delivered by the power supply is
normally insufficient to jump the switch gap in the form of an arc and the
electron flow in the circuit is blocked.
Load
Is a source drives a load, whatever component or piece of equipment is connected to
a source and draws current from a source is a load on that source.
Testing Electronic
Components
A Short Guide to Testing Electronic
Components
1. Switch on the multi-meter. Turn the knob to the resistance setting marked by
the symbol for the Greek letter Omega
2. Place a multi-meter probe on its resistor lead. Record the resistance
3. Place the multi-meter probes on other components leads. This can include
diodes, capacitors and photocells.
