pg 25-30 Domestic Electrical Installer – Module 6: Electrical Inspection, Testing and Documentation

Vocabulary flashcards covering key instruments, tests, standards and certification concepts from Module 6.

Separate Instruments

Individual electrical test devices (e.g., loop tester, insulation tester) used independently rather than as part of a single all-in-one unit.

Multifunction Tester (MFT)

A single instrument that combines several electrical tests (loop, insulation, RCD, continuity, etc.) into one device.

Non-contact Voltage Indicator

Hand-held detector that senses the presence of voltage without touching conductors; useful for identifying live circuits but not suitable for safe isolation.

GS38 Voltage Tester

Two-pole or approved tester that meets HSE Guidance Note GS38 requirements; must be proved on a known source before and after isolation.

Phase Rotation Indicator

Instrument used on polyphase circuits to verify that the phase sequence is correct, as required by BS 7671 643.9.

Clamp Meter

Tester that measures AC or DC current by sensing magnetic fields around a conductor without breaking the circuit.

Earth Fault Loop Impedance (Zs)

The total impedance of the earth fault current path (phase-earth-supply) measured to confirm fault protection.

Polarity Test

Verification that live, neutral and protective conductors are correctly connected throughout a circuit.

Insulation Resistance Test

Measurement of resistance between conductors and earth to ensure insulation integrity and prevent leakage currents.

R1 + R2 Measurement

Combined resistance of the circuit’s live (R1) and protective (R2) conductors, confirming continuity of the CPC.

Thermal Imaging Equipment

Infrared cameras that highlight temperature differences, helping locate electrical faults before contact measurements are taken.

BS 7671

British Standard outlining the IET Wiring Regulations governing design, installation, inspection and testing of electrical systems.

Minor Electrical Installation Works Certificate

Document (BS 7671 644.4.201) issued when work does not add a new circuit or replace a consumer unit, covering small additions or alterations.

Electrical Installation Certificate

Comprehensive certificate required for new installations or major alterations; alternative to a Minor Works Certificate for small jobs.

Safe Isolation

Procedure involving switching off, locking off, and testing with a GS38-compliant voltage tester to ensure a circuit is dead before work.

Guidance Note 3

IET publication providing detailed guidance on inspection and testing, including the use of thermal imagery tools.

Calibration

Annual verification and adjustment of test instruments to ensure measurement accuracy and compliance.

Part P Test Kit

Comprehensive set of separate instruments (loop, insulation, RCD testers, etc.) suitable for domestic installers working under Building Regulations Part P.

Ground-Earth Tester

Function or instrument that measures resistance of an earth electrode; often unnecessary for typical domestic MFT users.

“Spaghetti Junction”

Informal term for tangled test leads; reduced when using a single multifunction tester with one set of leads.