Electrical Installation Regulations Practice Flashcards

Comprehensive vocabulary flashcards covering the EtihadWE Electrical Installation Regulations Second Edition, including definitions of key components, technical calculations, and infrastructure requirements.

Point of Supply (POS)

The physical and contractual boundary between the EtihadWE distribution system and the consumer's internal electrical distribution, marking the point where EtihadWE responsibility ends.

Total Connected Load (TCL)

The total rated load of all appliances and other electrical equipment or points at a Premise.

Maximum Demand Load (MDL)

The maximum load in $kW$ an installation is expected to draw under normal operating conditions.

Nominal Supply Voltage

The electric supply voltage from EtihadWE specified as $240/415V \times \text{±}10$% in accordance with IEC 60038.

Power Factor (PF)

The ratio of real power to apparent power; consumers must maintain a minimum of $0.95$ lagging at the Point of Supply.

Voltage Drop Limit

The maximum accumulative voltage drop allowed from the POS to any end point, which shall not exceed $4$% of the nominal supply voltage.

Main Distribution Board (MDB)

The distribution board that receives the main LV supply from EtihadWE or the Customer’s transformer.

Sub-Main Distribution Board (SMDB)

A distribution board supplied by the MDB to distribute circuits within a designated area.

Final Distribution Board (FDB)

The last control and protection point in the installation that accommodates final circuits supplying lights, sockets, and AC units.

Circuit-breaker

A mechanical switching device that automatically interrupts a circuit under overload or short-circuit conditions.

Residual Current Device (RCD/ELCB)

A protective device that automatically disconnects the supply when the algebraic sum of currents in the live conductors reaches a preset value.

Earth Continuity Conductor (ECC)

A protective conductor used to connect exposed-conductive-parts of equipment to the main earthing terminal.

TT Earthing System

The required earthing system for consumer installations where the earthing system must achieve a resistance of $1 \text{ Ω}$ or less at the MDB.

Main Earthing Terminal (MET)

The main connection point for the installation’s protective conductors and earth electrodes, typically installed inside the MDB.

Advance Metering Infrastructure (AMI)

Advanced electronic meters with remote communications, extended measurements, and remote connect or disconnect capability.

Surge Protection Device (SPD)

A device designed to safeguard electrical systems and equipment against transient overvoltage caused by lightning strikes or switching operations.

Safety Extra-Low Voltage (SELV)

An extra-low voltage system providing protection against electric shock, commonly used for underwater lighting at a maximum of $12V \text{ AC}$ or $30V \text{ DC}$.

Ring Circuit

A circuit in which the conductors form a closed loop starting from and returning back to the origin.

Radial Circuit

A circuit supplied from a single origin that feeds points without looping back, used for large appliances like water pumps.

Transformer Room

A dedicated room required for installations with a TCL of $230 \text{ kW}$ and above, or an MDL between $200 \text{ kW}$ and $5 \text{ MW}$.

Switching Station

An infrastructure requirement for installations with an MDL exceeding $5 \text{ MW}$ up to $15 \text{ MW}$, with internal dimensions not less than $20\text{m} \times 10\text{m}$.

Trunking Filling Factor

Special factor used when installing cables in trunking, specifying that the total effective cable cross-sectional area must not exceed $40$% of the internal area.

Cable Tray Space Factor (Multi-core)

The filling factor limit for multi-core insulated and sheathed cables installed in cable trays, which must not exceed $60$%.

Capacitor Bank

Assemblies used to improve the power factor, required for industrial premises with a TCL of $100 \text{ kW}$ and above.

Harmonic Filter

A device used to mitigate harmonic distortion risks and resonance, typically provided in series with capacitors using $7$% detuned reactors.

Prospective Short-Circuit Current (PSCC)

The current that would flow under a short-circuit of negligible impedance between live conductors or between a live conductor and earth.

Isolator (Disconnector)

A mechanical switching device that provides clear physical separation in the open position for maintenance or safety.

Equipotential Bonding

Electrical connections intended to maintain exposed and extraneous-conductive-parts at substantially the same potential.

Imax Equation (FDB)

The formula used to calculate the maximum operating current defined as $Imax = \frac{\text{Load of Highest Phase (W)}}{192}$.

Ingress Protection (IP) Rating

The classification for the degree of protection provided by enclosures (e.g., $IP54$ for indoor distribution boards, $IP65$ for outdoor).