Question

State relative advantages and disadvantages of ring system of wiring over the tree system.

Answer 1

Advantages:
(i) The tree system of wiring requires the plugs and sockets of different sizes for different current capacities while they are all of the same sizes in the ring system of wiring.
(ii) The tree system of wiring has one fuse in one distribution line. If the fuse in one distribution line blows, it disconnects all the appliances in that distribution line. But in the ring system, a separate fuse is connected with each appliance. So if one fuse blows, it does not affect the other appliances.
(iii) The tree system of wiring is expensive while the ring system of wiring is cheaper.
(iv) It is expensive and inconvenient to install a new appliance in the tree system of wiring since it requires to put the new leads up to the distribution box, while it is easy to install a new appliance in the ring system since the appliance can be directly connected to ring mains in the room.

Disadvantages:
The only disadvantage of the ring system of wiring over the tree system is that while installing a new appliance, care has to be taken that the total load on the ring circuit does not exceed the main fuse rating (i.e., generally 30 amp.).