Socket-outlets situated off the main route of the cable do not have to be connected to the actual ring cable. Instead they are usually supplied from spur cables branching off the ring. These spurs are wired in the same size cable as that used for the ring.
Fixed appliances which may be connected to a ring circuit include skirting heaters, wall heaters, small water heaters and any non-portable electrical appliances having individual loadings of not more than 3000 W(13 A approx.). Read the rest of this entry »
Electric heating of water can be carried out in a variety of ways. These include small capacity heaters fitted above the sink, instantaneous sink heaters or immersion heaters in the hot water tank.
Small storage water heaters fitted over the sink or washbasin having capacities of up to about 3 gallons and electrical loadings of 1 to 3 kW are usually supplied from the ring circuit by means of a spur. Except in a bathroom, the outlet can be a fused plug and switched socket-outlet, preferably with neon indicator. Read the rest of this entry »
Storage heaters require a separate circuit for each heater. This is because, unlike direct acting heaters which are switched on and off as required, storage heaters are all switched on together during the 8-hour period. They cannot therefore be supplied from a ring circuit which is based on diversity of use of various appliances; each heater must have its own circuit. Read the rest of this entry »
Joint boxes are usually circular and for part of the circuit wiring. They are fix permanently to the house structure are used principally in lighting circuits. Join boxes are available in 4- 5- and 6-terminal versions.
A 3-terminal joint box of 30 A current rating is used for ring circuits to connect spur cables to the ring cable, as shown the illustration. Read the rest of this entry »
A fused clock connector is a small non- switched fused outlet designed expressly for supplying a mains electric clock.
The unit is in two sections: a fixed base which is connected to the fixed circuit wiring, and another section in.the form of a flat pin plug which plugs into sockets in the base. The plug section carries the flex of the clock and contains the fuse. The plug is secured in the base by a retaining screw. This prevents the plug being pulled out accidentally and stopping the clock. Read the rest of this entry »
