General > General Technical Chat
Junctioning 32A cooker circuit with a 13A spur.
PlainName:
--- Quote ---A standard UK ring circuit (It is a weird UK thing for the non UK crowd) is typically fed by a 32A breaker, and nobody worries about a 2.5mm spur to a single socket.
--- End quote ---
Perhaps because it's a ring circuit, not a single-ended job.
paulca:
--- Quote from: richard.cs on February 10, 2022, 05:10:13 pm ---Also, why not reduce the MCB feeding the 6mm cable to 16 A anyway? You may find the manufacturer's instructions (which you're supposed to "take account of") require that anyway, and that is a cheap and straightforward job.
--- End quote ---
That's a good point. With most UK appliances they come with a fuse in the "plug". The oven is a hardwire, it says it has a 16A 'fuse' requirement NOT a 16A circuit requirement. In Europe they apparently have a 16A 3 pin connector on a single 16A circuit... so ovens are often rated to 16A, not 13A like UK plug-in ovens. The short of it is... it expects to be on a 16A fused spur in Europe. So ... it probably doesn't have an internal fuse... and yes, should be fused at 16A at the consumer unit. I have a spare in there, need to check it's rating, I could get lucky, but Screwfix sell them pretty cheap.
--- Quote from: richard.cs on February 10, 2022, 05:10:13 pm ---*Why flex here though? A bit of 1.5 or 2.5 mm2 T&E to a FCU would seem more conventional. If you do use flex you should really use ferrules.
**FCU = fused connection unit. It's a thing we have in the UK that takes the same type of fuses as the plugs but is for permanently installed things.
*** These ignition things take a couple of milliamps.
--- End quote ---
* I figured it was easier to work with and would allow me to leave the socket floating on the floor of the cavity rather than trying to fix it up anywhere.
** FCU. Never heard of. Adds a new dimension.
*** Yea. The irony is I could probably run an ignitor circuit of a 18650 lion for months. Only the circuitry is obviously going to use the mains voltage.
EDIT: FCU: Is that just the fused spur panels with the switch they use for dishwashers/washingmachines? Ohh.... penny drop! Of course. They normally end up as a floating socket extension under the kick boards for easy use. The fuse in the spur panel is to fuse that bit of cable, even through the dishwasher/et.al. has it's own fuse (UK plugs).
paulca:
All done. Both cookers working.
6mm feed -> 60A junction 6mm + 2.5mm out. 2.5 goes to a single plug socket, 6mm goes to the new oven.
All I have as open items is to drop the 32A to a 16A MCB T3.
SteveyG:
--- Quote from: paulca on February 11, 2022, 05:49:06 pm ---
--- Quote from: richard.cs on February 10, 2022, 05:10:13 pm ---Also, why not reduce the MCB feeding the 6mm cable to 16 A anyway? You may find the manufacturer's instructions (which you're supposed to "take account of") require that anyway, and that is a cheap and straightforward job.
--- End quote ---
That's a good point. With most UK appliances they come with a fuse in the "plug". The oven is a hardwire, it says it has a 16A 'fuse' requirement NOT a 16A circuit requirement. In Europe they apparently have a 16A 3 pin connector on a single 16A circuit... so ovens are often rated to 16A, not 13A like UK plug-in ovens. The short of it is... it expects to be on a 16A fused spur in Europe. So ... it probably doesn't have an internal fuse... and yes, should be fused at 16A at the consumer unit. I have a spare in there, need to check it's rating, I could get lucky, but Screwfix sell them pretty cheap.
--- Quote from: richard.cs on February 10, 2022, 05:10:13 pm ---*Why flex here though? A bit of 1.5 or 2.5 mm2 T&E to a FCU would seem more conventional. If you do use flex you should really use ferrules.
**FCU = fused connection unit. It's a thing we have in the UK that takes the same type of fuses as the plugs but is for permanently installed things.
*** These ignition things take a couple of milliamps.
--- End quote ---
* I figured it was easier to work with and would allow me to leave the socket floating on the floor of the cavity rather than trying to fix it up anywhere.
** FCU. Never heard of. Adds a new dimension.
*** Yea. The irony is I could probably run an ignitor circuit of a 18650 lion for months. Only the circuitry is obviously going to use the mains voltage.
EDIT: FCU: Is that just the fused spur panels with the switch they use for dishwashers/washingmachines? Ohh.... penny drop! Of course. They normally end up as a floating socket extension under the kick boards for easy use. The fuse in the spur panel is to fuse that bit of cable, even through the dishwasher/et.al. has it's own fuse (UK plugs).
--- End quote ---
Most electric ovens and hobs these days tend to be designed for Europe. The nature of a heating cycle of an oven and hob mean it's unlikely to be a problem, but you can run into issues with the 13A plug getting pretty warm on appliances rated over 2 kW used for long periods, particularly in a poor quality socket.
It would have been acceptable to connect the oven and hob directly to the cooker supply with no additional fusing down, the oven itself is unable to create an overload situation (it's a fixed load), so provided the cable is adequately rated for the 3+ kW, nothing else is required. Of course you must do your tests to confirm the PFCC at the appliance is high enough to meet disconnection times.
There's no need to change the MCB.
themadhippy:
--- Quote --- so provided the cable is adequately rated for the 3+ kW, nothing else is required. Of course you must do your tests to confirm the PFCC at the appliance is high enough to meet disconnection times.
There's no need to change the MCB.
--- End quote ---
so a lump of 1mm protected by a 32A mcb is fine?
Navigation
[0] Message Index
[#] Next page
[*] Previous page
Go to full version