On Site Guide knowledge quiz

To which supply frequency is the On Site Guide guide restricted for installations? The supply frequency is ______ Hz.

• 50

• 60

• 100

• 25

oWhat is the nominal voltage for installations covered by the OSG ? The nominal voltage is ______ V AC single-phase or ______/______ V AC three-phase.

• 230; 400/230

• 220; 380/220

• 240; 415/240

• 210; 360/210

What is the typical maximum value of earth fault loop impedance (Z_e) for TN-C-S arrangement outside the consumer's installation? TN-C-S arrangement – ______ Ω.

• 0.35

• 0.55

• 0.80

• 1.00

What is the typical maximum value of earth fault loop impedance (Zₑ) for TN-S arrangement outside the consumer's installation?

• 0.8 Ω

• 0.4 Ω

• 1.2 Ω

• 1.5 Ω

Which standard has BS 3871-1 been replaced by for circuit-breakers?

• BS EN 60898-1:2019

• BS 88-2

• BS 951

• BS EN 62423

A permanent notice to BS 951 must be permanently fixed in a visible position at or near the point of connection of: Select all that apply.

• To all CPC terminals

• To all live cables

• At the main earth terminal (MET), where it is not part of the main switchgear

• Inside the consumer unit.

Protection against overload current will be provided by the use of ________ to BS 88-2 (BS EN 60269-2), BS 88-3, BS 88-6, BS 1361 or BS 3036.

• fuses

• relays

• transformers

• circuit breakers

A permanent notice to BS 951 must be fixed at the connection of every ________ conductor to an earth electrode.

• earthing

• neutral

• live

• phase

What does the label in Figure 6.4 indicate at the connection of earthing and bonding conductors?

• SAFETY ELECTRICAL CONNECTION DO NOT REMOVE

• DANGER: HIGH VOLTAGE

• EARTH CONNECTION ONLY

• DO NOT TOUCH: LIVE WIRE

What is the recommended frequency for testing a Residual Current Device (RCD) according to the notice shown in Figure 6.11?

• Monthly

• Every six months

• Annually

• Weekly