Inspection & Testing

What is initial verification in electrical installations?

• AMonthly checking
• BThe complete inspection and testing of a new installation before it is put into service✓
• CAnnual maintenance
• DNever required

Answer: Initial verification is the comprehensive testing required before an installation is energized.

What is an EICR (Electrical Installation Condition Report)?

• AA design document
• BThe report produced during periodic inspection of existing installations✓
• CA maintenance schedule
• DA warranty document

Answer: An EICR documents the condition of an existing electrical installation and identifies defects.

What is the typical interval for periodic inspection of a domestic installation?

• A1 year
• B3 years
• C10 years
• DEvery 5-10 years or on change of occupancy✓

Answer: BS 7671 recommends periodic inspection every 10 years for domestic installations, or on change of occupancy.

What is an EIC (Electrical Installation Certificate)?

• AA testing tool
• BA certificate confirming a new installation meets BS 7671✓
• CAn insurance document
• DA maintenance log

Answer: An EIC is the certification provided after successful initial verification of a new installation.

What is the main purpose of visual inspection before electrical testing?

• AAesthetic check only
• BTo identify visible damage, defects, and compliance issues before energizing✓
• CTo ensure good color matching
• DNo purpose

Answer: Visual inspection checks for physical damage, incorrect installation, and non-compliant work before testing.

Which test should be performed first on a new installation?

• AInsulation resistance
• BEarth continuity
• CVisual inspection✓
• DLoading test

Answer: Visual inspection must be completed before any testing to ensure it is safe to energize.

What is insulation resistance testing?

• ATesting cable outer cover strength
• BMeasuring the resistance between conductors and earth to verify insulation integrity✓
• CTesting circuit breaker operation
• DChecking conductor size

Answer: Insulation resistance testing uses a megohmmeter to verify insulation between conductors and earth.

What is the minimum acceptable insulation resistance for a 230V installation?

• A0.5 MΩ
• B1 MΩ✓
• C5 MΩ
• D10 MΩ

Answer: BS 7671 specifies minimum 1 MΩ insulation resistance at 500V DC test voltage.

What is the test voltage for insulation resistance on a 230V installation?

• A110V DC
• B230V DC
• C500V DC✓
• D1000V DC

Answer: Insulation resistance testing on low-voltage installations uses 500V DC as the test voltage.

What is protective conductor continuity testing?

• ATesting cable insulation
• BMeasuring the resistance of earth and bonding conductors to ensure low-resistance paths✓
• CTesting circuit breaker function
• DChecking voltage

Answer: Protective conductor continuity testing measures resistance of earth paths to verify they are adequate.

What is the maximum acceptable resistance for a protective conductor?

• A10 Ohms
• B1 Ohm
• C0.1 Ohms per connection, typically✓
• D100 Ohms

Answer: Protective conductor resistance should be very low, typically ≤0.1 Ohms at each joint.

What is earth fault loop impedance (Zs) testing?

• ATesting insulation
• BMeasuring the impedance of the complete fault current path to verify protection coordination✓
• CTesting voltage stability
• DCable capacity testing

Answer: Zs testing measures the impedance from the transformer secondary to the fault point, verifying overcurrent protection.