Transformers and Electrotechnology Concepts

These flashcards cover key concepts related to transformers and electrotechnology as discussed in the lecture.

Components of transformers

Typical components include the core, windings (primary and secondary), insulation, and cooling system.

Maximum induced voltage angle

The maximum induced voltage occurs at a 90-degree angle between the conductor and the magnetic field.

Magnet polarities

A magnet has a north pole and a south pole.

Unit of inductance

The unit of inductance is Henry (H).

Effect of reversing current flow

If the direction of current flow is reversed, the magnetic field surrounding the conductor also reverses.

AC equivalent of DC value

The term is Root Mean Square (RMS) value.

Secondary voltage generation process

The process is called electromagnetic induction.

High grade silicon steel in transformers

It is used to reduce energy losses and improve efficiency.

Defining AC frequency

The frequency of an alternating current supply is defined in hertz (Hz).

Danger tag removal authorization

Only authorized personnel or qualified electricians can remove a danger tag.

Standard voltage for single phase supply in Australia

The standard voltage is 230 volts.

Meter for testing circuit voltage

A voltmeter is suitable for testing circuit voltage.

Induced voltage changes with magnet speed

The induced voltage increases as the speed of the magnet moving in and out of the coil increases.

Standard voltage for three phase supply in Australia

The standard voltage is 400 volts.

Condition for induced voltage in a conductor

Relative motion between a conductor and a magnetic field must occur.

Meter for measuring current flow in HVAC & R

An ammeter is most appropriate for measuring current flow.

Work qualified refrigeration tradespersons can perform

They can perform electrical work related to refrigeration systems within their qualifications.

Function of an RCD (Residual Current Device)

The primary function of an RCD is to prevent electric shock by detecting imbalances in electrical current.

Electron flow in AC cycle

Electron flow alternates direction, completing one cycle by reversing back and forth.

Characteristics of a dead short

High current flow, potentially causing a drop in voltage and overheating.

Impedance in electrical circuits

Impedance refers to the total opposition to current flow in an AC circuit.

Components of impedance

Components include resistance, inductive reactance, and capacitive reactance.

Purpose of laminations in transformer core

Laminations are used to reduce eddy current losses.

Sine wave cycle

A graphical representation of alternating current depicting voltage over time in a sinusoidal shape.

Electrical safety tests

Insulation resistance test, earth continuity test, RCD test, polarity test, and functional test.

Main purpose of a transformer

The main purpose of a transformer is to transfer electrical energy between two or more circuits at different voltage levels.