uHeat Banner - Forum Discount Available
This official sponsor may provide discounts for members

Discuss Wagos on Final Ring Circuits in the Electrical Wiring, Theories and Regulations area at ElectriciansForums.net

Reaction score
25
Welcome to ElectriciansForums.net - The American Electrical Advice Forum
Head straight to the main forums to chat by click here:  American Electrical Advice Forum

In a ring if there is a 30A screw terminal junction box in the ring one spur can be taken off this. The j box terminals have three cables in them.

Each cable in a Wago (or an in-Sure) has it own connection slot for each wire. This makes a difference.
Wagos are mini bus bars. If a 32A four connector Wago has a 2.5mm wire in each end, then the brass 'bus bar' inside is obviously a part of the ring that full current can run through.

So, if a four connector Wago is in a junction box on a ring with the ring cables in each end, (must be in each end) then each of the centre two connectors can have a spur off, as both are off the mini bus bar in the Wago that forms a part of the ring. So two spurs off the one Wago, as both are independently off the ring.

What are the views of you guys.
 
Last edited:

Lucien Nunes

-
Mentor
Esteemed
Arms
Reaction score
7,332
It's a cheeky literal interpretation of the regs to bypass their intention. The idea is that with the ring cables in the end ports the Wago internal busbar spine forms part of the ring 'wiring' so the two inner ports are 'separate' locations in the ring, each of which is entitled to feed one spur. In fact if you allow that each piece of the busbar can form part of the ring, it doesn't matter which holes the wires are in, as Tel notes.

But it's a specious argument because the intent of the regulation is not so much about the actual connectors as the tendency for multiple spurs radiating from a point along the cable to concentrate load at that point. Two adjacent traditional round JBs would have the same effect and may be technically compliant but bad practice.
 
Last edited:
Reaction score
25
why can't the RFC wires be in the inner ports and the spur wires in the outer ports?
Thanks.
As I explained, the brass bar insie the Wago forms a bus bar. The ring current will run from one end to the other. Spurs off the two centre connectors are off the ring itself for sure. I gave an e.g., of a four connector, and that would not make much difference which way the wires are in the connector, but would make a difference with a five connector Wago.

With a five, if say the two ring wires were in one end, it is clear that three sockets (spurs) could be off one Wago. That is why I say having the ring cables off the end connections is important - to maintain the integrity of the ring.
 
Last edited:
Reaction score
25
It's a cheeky literal interpretation of the regs to bypass their intention. The idea is that with the ring cables in the end ports the Wago internal busbar spine forms part of the ring 'wiring' so the two inner ports are 'separate' locations in the ring, each of which is entitled to feed one spur. In fact if you allow that each piece of the busbar can form part of the ring, it doesn't matter which holes the wires are in, as Tel notes.

But it's a specious argument because the intent of the regulation is not so much about the actual connectors as the tendency for multiple spurs radiating from a point along the cable to concentrate load at that point. Two adjacent traditional round JBs would have the same effect and may be technically compliant but bad practice.
Thanks.
I would not call it cheeky, just looking at the construction of the Wago. Electrically having two or three sockets, or FCUs off the centre connections of the Wago is electrically sound, electrically it is safe - and it does conform to the literal interpretation. I have no idea what Wago or in-Sure's intentions were.

It is a work around for sure.
 
Last edited:
Reaction score
25
however it's configured, there's the danger of putting too much load on a single point of the ring.
Thanks.
I would not call that danger.
That would be more ring design and balancing with two much load on one leg. But, say one leg of a ring take 75% of the load. by the time it reach 32A (assuming a 32A mcb on the ring), the most used leg will only be drawing 24A, which is within the ~27A of the 2.5mm cable.

Having sockets off a ring in a kitchen with a number of high current drawing appliances off the ring within inches or feet of each other, could be classed bunching on a ring as most of the load is all at one location of the ring. That is an ultra common situation. This can be overcome by a balanced ring, having say leg one feed alternative sockets. There again - design.

Lucien Nunes highlighted putting two 30A J boxes next to each other on a ring with a spur off each, which is the same.
 

Lucien Nunes

-
Mentor
Esteemed
Arms
Reaction score
7,332
Exactly, so my point is that one does not need to go to extreme lengths to justfy where you are connecting the spurs if you are designing appropriately. There is nothing better or worse about the Wago example vs. the two JB's example. It's just a matter of whether you want to argue over the definition of a cable and whether the innards of a Wago qualify as one. The argument has nothing to do with either electrical safety or compliance with the intended meaning of the regulations.
 
Reaction score
25
It's just a matter of whether you want to argue over the definition of a cable and whether the innards of a Wago qualify as one.
Thanks.
Looking at the innards of a Wago block the brass bus bar clearly makes up a part of the ring if using say the five connector Wago with the ring wires at each end. There is no argument on that - it just does. The brass inside is more substantial than the cable, capable of taking a heavier load.

John Ward's vid on Wagos, heavily overloading them until they melted, was clear in that the cable melted before the Wago. Even using the no-name cheapo Chinese brand.

The regs were written with screwed terminal j boxes and sockets in mind, as that is what was there. It looks like technology has overtaken the regs. BTW, in Germany they sell sockets with Wago connectors on the back, eliminating screwed connectors.
 

Lucien Nunes

-
Mentor
Esteemed
Arms
Reaction score
7,332
I'm not sure if we are at cross purposes. Any terminal or junction box should be suitable for the rated current and the number of cables connected. That is a separate consideration to whether more than one spur should be fed from a single point in the ring.

The brass inside is more substantial than the cable, capable of taking a heavier load.
The relationship is not quite that simple, since the bulk resistance of the metal is not the main source of heat dissipation. That occurs chiefly at the point of contact between cable and connector, where the current density is highest. The main difference that the CSA of the structural parts of a bussed connector makes, is in the thermal resistance to ambient they provide to the points of high current density.

The regs were written with screwed terminal j boxes and sockets in mind,

When the regs were written, rings were normally wired in 7/.029. One can make a connection of lower resistance between two spurs and a through-run of 7/.029 in a 30A marshmallow, than one can between two spurs and a through-run of 2.5 in a 5-hole 222. The advantage of the Wago is that the contact resistance is consistently low across time, temperature and cable types, not that it is insignificant altogether. I am a great fan of Wagos having been using them since the 1980s, but they don't have magical powers.
 

Pete999

-
Esteemed
Arms
Reaction score
16,635
Thanks.
Looking at the innards of a Wago block the brass bus bar clearly makes up a part of the ring if using say the five connector Wago with the ring wires at each end. There is no argument on that - it just does. The brass inside is more substantial than the cable, capable of taking a heavier load.

John Ward's vid on Wagos, heavily overloading them until they melted, was clear in that the cable melted before the Wago. Even using the no-name cheapo Chinese brand.

The regs were written with screwed terminal j boxes and sockets in mind, as that is what was there. It looks like technology has overtaken the regs. BTW, in Germany they sell sockets with Wago connectors on the back, eliminating screwed connectors.
Just design the circuit/layout correctly in the first place, do away with JBs of any description MF or not, a decent circuit design beats the need for any joints, good planning beats Migraines caused by worrying if you have done it correctly in the first place, JBs are good for afterthoughts and nothing much else. Tin hat firmly on head.
 
Reaction score
25
Thanks.
In a new circuit what you wrote was the way to go. But it is the additions along the way that entail junctions, spurs, etc.

An e.g., my place. I have: w/machine, d/washer, boiler, fridge, boiler, TV amplifier & Modem, all on their own 2.5mm radial circuits with their own RCBOs. The ring circuit feeds the TV, laptop, 800w toaster and cooker hood. Minimal load. Divide and rule.

Looking at the Wagos, if I wanted to take a two spurs off say one of the kitchen sockets - out of convenience, the Wagos would do it at the rear of a 35mm deep backbox. Electrically safe? No doubt. To the regs, I would say yes. Others may disagree, that is the aim of this thread, to make awareness getting differing views. BTW, I have no intention of adding spurs.
 

Reply to Wagos on Final Ring Circuits in the Electrical Wiring, Theories and Regulations area at ElectriciansForums.net

Latest Posts

Top