6 terminal junction box

[redman]

hello all,

Ive just read through an asignment that I have to do for college.

It says "draw a wiring diagram & then install a 2 way lighting circuit using a 6 terminal junction box".

Im familiar with this type of circuit, but I have always used a 4 terminal JB.

Is there a particular reason to use a 6 terminal JB, or should I just do it the way I know & leave 2 empty terminals ?

Any ideas,

Cheers

 

[PC Electrics]

4 terminal JB for a two way cct?

In my head you need 6 terminals; live, neutral, earth, switched live, strapper 1, strapper 2. No?

 

[NozSpark]

It takes 5 terminals....

don't take the permanent live/switched live to the switch... just the strappers

 

[NozSpark]

You will have

1. Com (both switches)

2. L1 (Both switches) + permanent live

3. L2 (Both switches) + switched live

4. Neutral

5. Earth

 

[Evans Electric]

I'm sorry Redman but why is a JB involved , number of terminals irrelevent. I've only been in the trade for 100 years and I can't think how to introduce a 6 term JB .

Deke

 

[PC Electrics]

I'm sorry Redman but why is a JB involved , number of terminals irrelevent. I've only been in the trade for 100 years and I can't think how to introduce a 6 term JB .Deke

I would never use a JB for this type of install from fresh, but I can see why a student would need to learn about this method so they can recognise it out in the real world. Plenty of 60s and older houses with lighting circuits based around JBs.

As Noz points out, it can be done with 5 terminals, I just assumed you were meant to use all 6 for the purpose of the assignment.

 

[redman]

I'm sorry Redman but why is a JB involved , number of terminals irrelevent. I've only been in the trade for 100 years and I can't think how to introduce a 6 term JB .Deke

This is what Im unsure about.

Up until now, ive been doing the loop-in ceiling rose method.

Ive done a 1way light circuit through a 4 terminal JB,

I thought to make it a 2way circuit, I could just run the 3 core & earth from the first switch to the second.

 

[PBC_1966]

You can use 6 terminals if you use the traditional 2-way wiring arrangement with everything brought back to the junction box:

1. Supply L, common of first switch.

2. Traveler 1 between switches.

3. Traveler 2 between switches.

4. Common from second switch, L out to light.

5. Supply N, N to light.

6. Earth.

 

[SPECIAL LOCATION]

I'm sorry Redman but why is a JB involved , number of terminals irrelevent. I've only been in the trade for 100 years and I can't think how to introduce a 6 term JB .Deke

Introduce a 6 term J-box... ???? ffs Deke didn't you go to finishing school.. here you go mate:

You invite a friend and your 6-term JB to a diner party you lay on...

As they arrive you would go.. (lets assume Green Hornet is the friend who has come round).

Good evening Mr Hornet this is Mr 6-term J-Box,

and Mr J-box this is Mr Hornet.

that introductions all done now...

Starters is leek and potato soup..

then main course is a choice of meats or fish.

O) :Blushing

Simples! ; \ :^O :^O

 

[Evans Electric]

Introduce a 6 term J-box... ???? ffs Deke didn't you go to finishing school.. here you go mate:You invite a friend and your 6-term JB to a dinner party you lay on...

As they arrive you would go.. (lets assume Green Hornet is the friend who has come round).

Good evening Mr Hornet this is Mr 6-term J-Box,

and Mr J-box this is Mr Hornet.

that introductions all done now...

Starters is leek and potato soup..

then main course is a choice of meats or fish.

O) :Blushing

Simples! ; \ :^O :^O

Wet Fish

Wheres the clapping Smilie gone , I wish certain people would stop messing around with them.

I just don't get the logic of it, why not just do a 2 way circuit .

How about a ring main using 10 4 terminal JBs and some taped up connectors shoved under the floor with the two ends connected to different breakers. :coat

 

[Evans Electric]

Brian says its time for bed.

 

[SPECIAL LOCATION]

You can use 6 terminals if you use the traditional 2-way wiring arrangement with everything brought back to the junction box: 1. Supply L, common of first switch.

2. Traveler 1 between switches.

3. Traveler 2 between switches.

4. Common from second switch, L out to light.

5. Supply N, N to light.

6. Earth.

Concur with PBC here..

Although in the real world I would never do it this way..

I guess college is wanting you to bring four cables back to one J-Box

so just repeating PBC's solution with different wording..

e.g.

cable 1 T&E supply

cable 2 T&E to load (light)

cable 3 3core+E to switch 1

cable 4 3core+E to switch 2

Terminal 1 -- Cable1(Brown) & Cable3(Brown) {permanent Live}

Terminal 2 -- Cable3(Black sleeved Brown) & Cable 4(Black sleeved brown) {strapper}

Terminal 3 -- Cable3(Grey sleeved Brown) & Cable 4(Grey sleeved brown) {strapper}

Terminal 4 -- Cable4(Brown) & Cable2(Brown) {Switched Live}

Terminal 5 -- Cable1(Blue) & Cable2(Blue) {Neutral}

Terminal 6 -- Cable1,2,3 & 4 CPC's {Earth}

But make sure your J-Box is accessible if you ever do anything this way in the real world.

:coffee

 

[PBC_1966]

I just don't get the logic of it

It could save some lengthy cable runs in some cases. For example, imagine that the light is near the source of power and the two switches are in opposite directions from that point and a considerable distance away.

 

[SPECIAL LOCATION]

Wet FishWheres the clapping Smilie gone , I wish certain people would stop messing around with them.

Brian has been using his clone brothers to round em up..

:Applaud :Applaud:Applaud:Applaud:Applaud

:Applaud :Applaud:Applaud:Applaud:Applaud

:Applaud :Applaud:Applaud:Applaud:Applaud

:Applaud :Applaud:Applaud:Applaud:Applaud

X(

 

[redman]

You can use 6 terminals if you use the traditional 2-way wiring arrangement with everything brought back to the junction box: 1. Supply L, common of first switch.

2. Traveler 1 between switches.

3. Traveler 2 between switches.

4. Common from second switch, L out to light.

5. Supply N, N to light.

6. Earth.

Nice one mate,

Think Ive got it now.

 

[SPECIAL LOCATION]

It could save some lengthy cable runs in some cases. For example, imagine that the light is near the source of power and the two switches are in opposite directions from that point and a considerable distance away.

:Applaud

could also have possible uses between floors if direct routes between switches not feasble....

I suppose with copper prices rising there may be some financial argument to boxing on occasion?

:|

 

[PBC_1966]

I thought to make it a 2way circuit, I could just run the 3 core & earth from the first switch to the second.

You can. If you start with a simple 1-way switch loop, you can run 3-core to the second switch position to convert to 2-way. There are then two different ways you can make the connections at the first switch box:

Method #1. Put the two conductors from the loop into L1 & L2, then use the 3-core to connect the switches together L1 to L1, L2 to L2, and COM to COM.

Method #2. Put one side of the switch loop to COM at the original switch location, connect the other side of the loop through to COM at the second switch, and use the remaining two cores of the 3-core cable to link L1 to L1 and L2 to L2.

But when you have two (or more) switch locations plus the light, there are numerous ways in which to wire them, depending upon the relative positions, ease of pulling cables, etc.

For example, if the best overall cable run is source -> switch 1 -> switch 2 -> light, there's no need to take the permanent L feed beyond switch 1, so you can use a 3-core between the switches which has N plus the two travelers.

 

[PBC_1966]

Here are some very quickly drawn and crude diagrams illustrating some of the possible methods.

1 - Central junction box using 6 terminals

2 - Central junction box using 5 terminals

3 - 3-core cable between switches, method #1.

4 - 3-core cable between switches, method #2.

5 - Linear cable run with switches between supply & light.

Earths omitted in all cases for clarity & diagrams use "old" colors - Translate to new as required.

 

[Apache]

PBC they are nice diagrams. Could I suggest you add them to the downloads area so they don't get lost!

 

[SPECIAL LOCATION]

PBC they are nice diagrams. Could I suggest you add them to the downloads area so they don't get lost!

They are good drawings....

But also amend then to current colours codes...

Brown/Black/Grey

NOT

Red/Yellow/Blue

:Blushingray