Three phase

[tony112]

Can any1 please tell me where I can see pics of a three phase board up close to see how they are connected up etc? It's for a course for designing instructional material but I cant find a single decent pic. Maybe some1 could do a decent drawing showing lights motors and busbar connections if poss. Thankyou for any help. Much appreciated.

 

[ban-all-sheds]

Try the makers of 3-phase boards?

 

[plugwash]

Can any1 please tell me where I can see pics of a three phase board up close to see how they are connected up etc? It's for a course for designing instructional material but I cant find a single decent pic. Maybe some1 could do a decent drawing showing lights motors and busbar connections if poss. Thankyou for any help. Much appreciated.

something like this?



a 3 phase DB and a domestic CU are really quite similar. you still have a neutral bar a main incomer and mcbs the only real differences are in size ,layout, the provision needed for the extra two phases and the bang when you get it wrong.

 

[Big_Spark]

Plug..that's un untidy board!! hnehehe, anyway it's wrong as it is the OLD colour system, if he is doing instructional material it should be in the new colour scheme. Sorry to pick holes..

 

[kai]

It's a mixture of systems, there is a blue NEUTRAL cable with Black Tape wrapped around it at the bottom right terminal block!

 

[andy]

It's a mixture of systems, there is a blue NEUTRAL cable with Black Tape wrapped around it at the bottom right terminal block!

so we have 2 blues in there, 1 on a phase and 1 at neutral... how dangerous...

 

[plugwash]

strangely i don't see anything that would go with that blue neutral. IE no brown lives or yellow earths (a yellow earth would mean a 3 core SWA being used for single phase)

still the basic layout is clear enough in that image

 

[andy]

strangely i don't see anything that would go with that blue neutral. IE no brown lives or yellow earths (a yellow earth would mean a 3 core SWA being used for single phase)

still the basic layout is clear enough in that image

i cant see any brown lives either... looks like someon is takin the shared neutral to the extreme

and whilst were on about 3 phase boards, why is the neutral not switched thru the isolator unlike a single phase board?

 

[plugwash]

afaict on 3 phase TN systems you don't have to isolate the neutral (on single phase i don't think you have to if the isolator is only for use by skilled persons)

some brands of 3 phase board can be fitted with either a 3 pole or a 4 pole incomer kit others only have space for a 3 pole incomer.

 

[ryanj]

Mmm. Wiki-image.

 

[Big_Spark]

The board is a mess. You have TPN Incomer using the old colour sode system.

Not only does it mix the colour systems with no clear indication, potentially causing dangerous confusion, it also has a PURE Yellow conductor as the Incoming CPC, even though there is clearly a PURE Yellow conductor used for the L2 Yellow Phase Incomer.

Further, if you look carefully at the Neutral Bar Extension (Top right of picture) there is clearly another Yellow Conductor in this terminal bar.

Whoever made this board off needs to attend college as that Board is an amateurish mess.

 

[andy]

The board is a mess. You have TPN Incomer using the old colour sode system.

Not only does it mix the colour systems with no clear indication, potentially causing dangerous confusion, it also has a PURE Yellow conductor as the Incoming CPC, even though there is clearly a PURE Yellow conductor used for the L2 Yellow Phase Incomer.

Further, if you look carefully at the Neutral Bar Extension (Top right of picture) there is clearly another Yellow Conductor in this terminal bar.

Whoever made this board off needs to attend college as that Board is an amateurish mess.

even my 3 phase board i wired the other day is better than that! looks bit untidy inside, but at the same time its safer than that. all colours are correctly marked etc

 

[plugwash]

The board is a mess. You have TPN Incomer using the old colour sode system.

Not only does it mix the colour systems with no clear indication, potentially causing dangerous confusion, it also has a PURE Yellow conductor as the Incoming CPC, even though there is clearly a PURE Yellow conductor used for the L2 Yellow Phase Incomer.

Further, if you look carefully at the Neutral Bar Extension (Top right of picture) there is clearly another Yellow Conductor in this terminal bar.

Whoever made this board off needs to attend college as that Board is an amateurish mess.

that bar on the top right seems like an earth bar to me it seems like a board that has a neutral bar and an earth bar on each side

It looks to me like the whole board is old colours and that the blue neutral and yellow earth are the result of using 3 core SWA for single phase

 

[Big_Spark]

that bar on the top right seems like an earth bar to me it seems like a board that has a neutral bar and an earth bar on each side

You are correct, I enlarged the image and what I though initially was a Neutral Bar link is in fact a Link to the metal structure of the enclosure.

It looks to me like the whole board is old colours and that the blue neutral and yellow earth are the result of using 3 core SWA for single phase

Plug, think about what your actually looking at, The SWA maywell be a 4 Core, hence the R/Y/B/Black, but that does not explian the Yellow core that seems to be providing the Main Earth Connection to the Terminal Bar.

If you want an example of how not to terminate a DB then this is it. Many of the cores are too short, there is no clear identification for Neutral and Earth cores of particular circuits, why are the individual cores of given circuits not indicated as such by the use of cable ties to bunch them together?

 

[Steve]

lets have a pic of a properly terminated 3 phase board then.