Level 2 - 8202 - Protective devices and Co-ordination

Protective conductor current is the term used in BS 7671 to describe earth leakage current.

• True

• False

To achieve current co-ordination in a distribution system, the downstream device must have a higher continuous current rating than the upstream device.

• True

• False

S-Type RCD’s are designed to operate more slowly than standard RCDs, thus minimising the risk of nuisance tripping.

• True

• False

Protective devices are placed in the line conductors.

• True

• False

The point at which the two time/current characteristics cross is called the limit of discrimination.

• True

• False

The fuse carrier is the part of a fuse designed to melt when the fuse operates.

• True

• False

One advantage of a BS88-3 (2010) fuse is that is has no moving parts.

• True

• False

Type C circuit breakers are designed to trip at fault currents of 3–5 times I_n.

• True

• False

Residual current devices (RCDs) are designed to disconnect the supply if the current flow to earth exceeds a predetermined value.

• True

• False

Overcurrent protective devices are designed to operate under both overload and fault current conditions.

• True

• False