13A FCU from spur - maximum draw?

[iwaters]

In my attached garage I have a supply coming from a spur in the house which has a 13A FCU on it. This currently runs two 5ft flourescent lights and two sockets. However, I want to move a small chest freezer (don't have the power details unfortunatley) into the garage and that to run off one of the sockets. I want to change the other socket to a double. This will be used for hand-held power tools and a small-ish vacum cleaner (1200W). As far I as I can tell the bigest power draw from my tools is (2400W). Is this going to be too much for the supply I have?

Edit - Forgot to mention, the spur comes from a socket running on a RCD protected MCB (15A I think) in the CU - I assume this is a ring but I am not sure.

 

[securespark]

If it is a spur off a true ring circuit, then 13A is the maximum load.

Some here say that an MK double socket is rated to 26A, but I have not had any confirmation from MK tech yet.

 

[ban-all-sheds]

In my attached garage I have a supply coming from a spur in the house which has a 13A FCU on it.

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Is this going to be too much for the supply I have?

Dunno - will it come to more than 13A?

Edit - Forgot to mention, the spur comes from a socket running on a RCD protected MCB (15A I think) in the CU - I assume this is a ring but I am not sure.

Unlikely, if it's a 15A MCB.

 

[333rocky333]

Watts = volts X amps
Amps = watts divided by volts
using volts as say 230 volts

2400 divided by 230 = your estimated load

The freezer may have a plate near where the cable goes into it with the rating on it

 

[FingRinal]

Some here say that an MK double socket is rated to 26A, but I have not had any confirmation from MK tech yet.

Secure, it is documented in the MK literature. If memory serves, MK produce a 'sales' brochure and a 'technical' brochure (can't remember the exact titles) and I'm fairly sure it's the technical one you need (although it might be in both). Both are free to download. I think you need to search for 'Sentry' on their web site.


EDIT:
Sentry is Consumer Units etc...try this
http://www.mkelectric.co.uk/PDF/technical/LOGIC_PLUS_tech.pdf

 

[GaryMo]

Secure, it is documented in the MK literature. If memory serves, MK produce a 'sales' brochure and a 'technical' brochure (can't remember the exact titles) and I'm fairly sure it's the technical one you need (although it might be in both). Both are free to download. I think you need to search for 'Sentry' on their web site.


EDIT:
Sentry is Consumer Units etc...try this
http://www.mkelectric.co.uk/PDF/technical/LOGIC_PLUS_tech.pdf[/QUOTE]

That's the one!

 

[iwaters]

Doing the maths then, using a 2400W saw and a 1200W vacuum together would equal a load of just over 15A. So why doesn't this blow a 13A FCU?

Lets say for example that I draw too much current. What is the worse that will happen? Is it just that the FCU fuse will blow, or something worse?

Could I use a junction box to split the supply coming into the garage and send a supply to the freezer which does not go through the FCU and then another supply going to the switches which does? Therefore if the FCU blows it wont affect the freezer. Or is this a big no-no?

Also, the lighting currently does not go through the FCU. Is this correct or should I change it so the supply to the light does go via the FCU.

Thanks for all your comments so far.

 

[333rocky333]

Doing the maths then, using a 2400W saw and a 1200W vacuum together would equal a load of just over 15A. So why doesn't this blow a 13A FCU?

Lets say for example that I draw too much current. What is the worse that will happen? Is it just that the FCU fuse will blow, or something worse?

Fuses are generally slower to function than mcb's
A 13 a fuse will run overloaded for a certain amount of time before it blows.
The 15 amp mcb will also take an overload for a certain amount of time before it trips.

Due to the way the mcb works I would say it is possible that
With say an overload of say 18 amp it would be more likely the 15 amp mcb after a period of time, would trip, and possibly before the 13 amp fuse blew.

It would not be a good idea to persist running it overloaded though,as it will eventually do more damage.

Providing the cables are suitably sized the above temporary overload in my example, should not have any adverse affect on the cable