consumer unit overloaded?

[wennners]

Hi Gents I hope you can help and advise?

I have just bought a 5 bedroom house that was supposedly rewired some time in the 90's, the consumer box is a 12 slot split load with a 80 amp rcd

My question is regarding the load limits of the consumer box on the outside it says not to exceed the switched rating.
Now on the 100amp side it is at 80amps and on the RCD side its at 70 amps total 150amps

Is this correct or is the consumer box over loaded?

 

[JohnD]

Look at the big supply cables that come out of the CU and go to the meter. From the meter they go to a service head, probably black plastic. You may see a company fuseholder here with a rating on it. Most likely it says "80 Amps" or "100 amps" engraved iin white lettering.

What does it say?

How is your house heated? And the hot water?

How many electric cookers and electric showers do you have?

 

[wennners]

The rating says 100 amps,

The heating is gas central heating, by combi boiler

There is no electric showers,

The stove is a gas hob and oven with an electric grill which is powered by a plug socket

 

[JohnD]

If the supply is fused at 100A then you can assume the max load it can draw is that (or the suppliers fuse will blow) and that this will prevent an overload (although in fact supplies fuses are quite tolerant of overloads and slow to blow.

However as you do not have electric heating, shower or cooking your typical electricity usage is probably no more than 10A (have a look at the meter and see).

In my own house the average usage is about 25kWh per day which is less than 5A (I have gas cooking and boiler)

The fact that you have lots of circuits and sockets just means you have the flexibility to plug things in if you want, but if you ever actually used 100A at a time you would need 7 or 8 large appliances running at the same time, such as fan heaters and tumble driers, and your house would be very hot.

There are ways of calculating design loads for electrical installations which allow for the fact that you are unlikely to run lots of things at the same time, if you want to do this I am sure you will find your design load is way under 100A

If you were using 100A it would cost you about £2 an hour in electricity.