Electrical Tools, Testers and Measurement Instruments

Hand Tools for Electrical Work

PLIER TYPE: A hand tool consists mainly of two parts: one part is the hand grip, which is held by the operator, and the other is the working section where the various tasks are performed.

Screwdrivers and Screwing Tools

SCREWDRIVERS or screwing: There are many types of screwdrivers. Initially, the most commonly used are flat-blade screwdrivers and star/Phillips screwdrivers.

• Flat-tip (slotted) screwdriver: Its use is indicated to tighten, loosen, or remove all types of screws that have an appropriate slot in the head.
• Star / Phillips screwdriver: This other type of screwdriver is widely used for cross-head screws.

Voltage Detectors and Testers

VOLTAGE DETECTOR: This is a type of screwdriver-shaped tool that also serves as a voltage tester for electrical outlets and circuits.

Cutting, Stripping, and Riveting Tools

ELECTRICIAN'S KNIFE: A knife with a straight, sharp steel blade used for general cutting tasks.

STRIPPERS and rivets: Tools used to strip insulation from cables and to crimp or rivet special terminals for subsequent electrical connections.

Magnetic Field and Its Definition

The magnetic field: A magnetic field is a region of space in which a moving point electric charge of value q and velocity v experiences a force that is perpendicular to both the velocity and the field. The field is characterized by the magnetic induction, also called magnetic flux density.

The magnetic field is a region of space in which a point electric charge value q, moving at a speed, suffers a force that is perpendicular and proportional to the speed and the field, called magnetic induction or magnetic flux density.

Metrology and Measuring Instruments

Metrology: The science of measurement. It studies measurement systems in any field of science and aims to ensure indirect and direct measurement quality.

Measuring instrument is a device used to compare or determine physical quantities through a process of measurement.

Specific Electrical Instruments

Galvanometer: An instrument used to detect and measure electric current. It is an analog electromechanical transducer that produces a rotational deflection of a needle or pointer in response to current flowing through its coil.

Ammeter: An instrument used to measure the current (amperes) flowing through an electrical circuit.

Magnetoelectric: To measure current in a circuit, the ammeter must be connected in series with the power source and the load (receiver).

Voltmeter: An instrument used to measure the potential difference between two points in an electrical circuit; it is connected across (in parallel with) the circuit elements whose voltage is to be measured.

Ohnimetro: An ohmmeter (or ohm-meter) is an instrument for measuring electrical resistance.

Fundamental Electrical Laws

Ohm's Law: Ohm's Law states that the electric current flowing through a conductor between two points is directly proportional to the potential difference (voltage) across the two points, provided the physical conditions such as temperature remain constant.

Kirchhoff's Law: There are two Kirchhoff laws commonly used in circuit analysis:

• Kirchhoff's Current Law (KCL): also called the law of nodes or the junction rule — the algebraic sum of currents entering a node (or a junction) equals the sum leaving the node.
• Kirchhoff's Voltage Law (KVL): also called the mesh or loop rule — the algebraic sum of all voltages around any closed loop in a circuit equals zero.