List the five essential requirements for device designed protect
against overcurrent. According IEE Regulation 411.4s
c.
15. overcurrent
c. 5.
14. overload current
d.2s
b. very low resistance
c.
13. fault protection
b.11. Briefly explain why electrical installation needs protective devices. ensure the effective operation the overcurrent protective devices,
the earth fault loop path must have:
a. short-circuit current. 0.
17.3. unlimited. List the four factors which the selection protective device
depends.
.
19. 0.
16. very high resistance.2. current which exceeds the rated current otherwise healthy
circuit one definition of:
a. consumer unit. fuse
d. The weakest link the circuit designed melt when overcurrent
flows one definition of:
a. Briefly describe the action fuse under fault conditions. State the meaning ‘discrimination’ applied circuit protective
devices. circuit protective conductor
c.
12.2 all final circuits not exceeding
32A building supplied with 230V supply shall have a
maximum disconnection time not exceeding:
a.0s
d.
18. 230V supply
b. fuses MCBs the live conductor
d. fault protection
b
