Circuit advice

[wondadust]

If i was to insert an fcu where the two red x's are would this circuit be ok if not what would i have to do to make it work?
Thanks to all
Andy

 

[davy_owen_88]

This is probably the best solution:

Adding the FCU's would work, but its not an ideal solution. Do you use any high powered appliances in that room (heaters)?

What size cables are used? What is the fuse/MCB rating? Are the X's currently junction boxes?

Davy

 

[wondadust]

Thanks Davy for the speedy reply
turning it in to a ring main is not an option the cable is 2.5mm and the x's are currently junction boxes and there will be no high powered appliances attached will be used for used for table lamps tv dvd mobile phone charger ect .The mcb is 6amp

 

[davy_owen_88]

With a 6A MCB there's really no need to fit the FCU's as long as all the cable is 2.5mm^2. The only reason I can think of for fitting them would be isolation purposes.

Are you having problems with the circuit as it is? Were you intending to upgrade the MCB or just thinking of bringing it up to current standards?

Davy

 

[wondadust]

Davy the cable is all 2.5mm and the circuit is fine no trips so the 6amp mcb is staying, i was just wondering if the spur situation was ok with just the use of junction boxes or if they needed to be replaced with fcu's to bring it up to standards
Andy

 

[JohnD]

As it is stuffed with sockets, sooner or later it will have something plugged in that will trip the MCB.

Why has a 2.5mm radial got a 6A MCB on it?

You could turn it into a 20A radial using Davy's diagram but removing the old link at the top. Or use his ring diagram, why do you say that's not an option?

I don't like JBs.

 

[wondadust]

The circuit is installed on a narrowboat. the shore power is limited to only 6amps from the incoming junction box this has a 6mp mcb in it. The 6amp mcb in the boat cu is used so that if it does overload it is that one that trips and not the one in the junction box, this is locked and needs to be reset by the mooring office not an option after 5pm there not that freindly at the best of times!.

not possible to turn it into a ring main as the cable would have to go through 3 steel bulkheads and a water tank

 

[davy_owen_88]

not possible to turn it into a ring main as the cable would have to go through 3 steel bulkheads and a water tank

Well that's a good enough reason for me

Don't bother fitting the FCU's unless you want them for isolation purposes. The 6A fuse is suitably protecting the wiring so adding FCU's would be pretty pointless.

Davy

 

[Chivers7]

Personally I'd rather have a FCU than a joint box and at least you could isolate the circuit in question for maintenance which is fairly often on a boat.