How many socket outlets can I have on a circuit?
Many houses that were built and wired in the late 1960’s to mid 70’s had very few socket outlets. There were not as many appliances and items that require charging as there are in the modern household. One was considered posh if there was a colour TV in the house, let alone one in every room. It was common therefore to just have a single socket outlet in each bedroom a twin in the dining room and two in the lounge.
In today’s modern household where there are all sorts of time saving devices, Wi-Fi connected equipment and entertainment devices, there is more requirements to have several socket outlets available in each room. The institute of electrical engineers recommend that there is no more than one meter of trailing extension or connection lead to an appliance and therefore a socket outlet every two meters for convenience. This means that there could be over 66 twin sockets in a three-bedroom house.
We then come to the commonly asked question: how many socket outlets can I have on a circuit? The answer is unlimited provided certain conditions are met.
First, we have the overcurrent protective device to consider.
If we have a ring main with a 32 amp miniature circuit breaker protecting the circuit, then even if we have 50 socket outlets, each capable of plugging a 13 amp piece of equipment to the ring then it is obvious that the 630 amps being used would not get passed the circuit breaker. To be fair, apart from a kitchen and/or utility room, a general household do not use that much power from a ring main. Most of the big current using equipment is in the kitchen.
The second thing we look at is the length of the cable run.
This is for volt drop purposes and providing the run of the cable is within the constraints for volt drop – 100 square meters for a ring main or 35 meters for a 16 amp radial circuit (both using 2.5mm cable), then we can rely on the overcurrent device, as mentioned previously.