Discuss 20A switch & 13A skt off ring in the Electrical Forum area at ElectriciansForums.net

Welcome to ElectriciansForums.net - The American Electrical Advice Forum
Head straight to the main forums to chat by click here:   American Electrical Advice Forum

Reaction score
115
A final ring circuit. A 20A switch spur off the ring feeding a single 13A socket supplying a Modem in a large plastic Modem box. The spur is restricted to 13A and only one outlet, appearing to conform. Do regs say the fuse has to be at the tapping of the ring?
 
Think grid switches for kitchen appliances.
20A DP switch as spur point off the rfc.... each spur is unfused to one point. Be that a socket or whatever.

the spur only needs a fuse if it is then supplying more than one point.
Yes, a fuse will be on the spur, being a 13A socket it has to be. Yes, gridswitching makes it clear the fuse can be downstream from the tapping on the ring, as long as the spur cable is protected. thx
 
You can spur once from RFC's at any point. Any outlet point, any cable (joint box) or at the circuit origin. Imagine FCU's at the side of sockets, under floorboards or inside consumer units, even, for every single spur point.
 
Appears people get confused at taking a spur from behind a socket. The terminals of a socket act as a junction box for the main current carrying spine of the ring. Theoretically, a socket is a spur off the main ring - look at the brass bits inside it to the three pin receivers, they spur off the terminals.
 
The opening question was solved. As long as the spur is protected by a 13A fuse, at any point along it, then all is well. You can have as many switches on the spur as you like then.

Bus bars?
 
Last edited:
If more than one point, the spur has to be fused at its source, not any point along it.
 
That conflicts with others here. Ref?
If you put individual FCU's for each point on an un fused spur, the additional points could lead to the load being too high for the spurred cable. With an existing spur, for example, all additional loads should be via one FCU.
 
Last edited:
If you put individual FCU's for each point on an un fused spur, the additional points could lead to the load being too high for the spurred cable. With an existing spur, for example, all additional loads should be via one FCU.
I believe John said switches, not FCUs


Hang on a minute! I can't believe I'm defending the Wago busbar advocate! ?
 
I believe John said switches, not FCUs
No difference, it's still load.

Bit of confusion spotted. It's the english. I've misconstrued 'at any point' as 'at any individual point', leading to thinking each fused unit being individual and local to the points.
Sorry.....but would maybe be better as 'the same 13A fuse at all points'.

The opening question was solved. As long as the spur is protected by a 13A fuse, at any point along it, then all is well. You can have as many switches on the spur as you like then.

Bus bars?
 
Last edited:
No difference, it's still load
A switch is not a load. John, being John, is arguing that the line to the load can be switched by any number of switches. Not that there would be any point to that, of course.
I think that's what John, being John, is saying...?
 
A switch is not a load. John, being John, is arguing that the line to the load can be switched by any number of switches. Not that there would be any point to that, of course.
I think that's what John, being John, is saying...?
No, but it's purpose is to switch load. ?

I'm losing meself here. Look on U tube....someone'll prove something or other with a video.?
 
A switch is not a load. John, being John, is arguing that the line to the load can be switched by any number of switches. Not that there would be any point to that, of course.
I think that's what John, being John, is saying...?
The spur line to the load can have multiple switches, however you correctly gleened this would be pointless.

You are right in correcting others in that a switch is not a load.
 
The spur line to the load can have multiple switches, however you correctly gleened this would be pointless.

You are right in correcting others in that a switch is not a load.
'Others'?
 

Reply to 20A switch & 13A skt off ring in the Electrical Forum area at ElectriciansForums.net

OFFICIAL SPONSORS

Electrical Goods - Electrical Tools - Brand Names Electrician Courses Green Electrical Goods PCB Way Electrical Goods - Electrical Tools - Brand Names Pushfit Wire Connectors Electric Underfloor Heating Electrician Courses
These Official Forum Sponsors May Provide Discounts to Regular Forum Members - If you would like to sponsor us then CLICK HERE and post a thread with who you are, and we'll send you some stats etc

Electrical Forum

Welcome to the Electrical Forum at ElectriciansForums.net. The friendliest electrical forum online. General electrical questions and answers can be found in the electrical forum.
This website was designed, optimised and is hosted by Untold Media. Operating under the name Untold Media since 2001.
Back
Top
AdBlock Detected

We get it, advertisements are annoying!

Sure, ad-blocking software does a great job at blocking ads, but it also blocks useful features of our website. For the best site experience please disable your AdBlocker.

I've Disabled AdBlock