3 phase question

[jon jordan]

hi guys
can someone explain to me this
a 3 phase supply to bungalow ok
one phase to house ok live
neutral& earth in henley blocks in meter box

neutral to 3phase meter from henley block

we have l1 l2 l3 lives to tpn 100amp switch fuse ( no neutral )
earth connection via earth block

from there we have a 16mm 4 core swa ( black ,red ,blue & yellow)
black --l1 fuse
red-- l2 fuse
blue--l3 fuse
yellow -- earth to henley block

thus feeds a 3phase board in workshop
No neutral to it.

1..???? is why is there no neutral to it
its not connected to earth
swa at cu is bonded at the armourings back to earth connection in board
and not at tpn ( discrimination)

2..??? why does all the 3phase equipment still work without a neutral

i am having to update a single phase cu to a 6 way to accomodate a solar pv 9.9kw system
luckily its got a 10.mm feed to it.

thanks
jon

 

[MDJ]

I expect they connected the Neutral straight to the dbs and not through the switch fuse.

 

[GLENNSPARK]

hi guys
can someone explain to me this
a 3 phase supply to bungalow ok
one phase to house ok live
neutral& earth in henley blocks in meter box

neutral to 3phase meter from henley block

we have l1 l2 l3 lives to tpn 100amp switch fuse ( no neutral )
earth connection via earth block

from there we have a 16mm 4 core swa ( black ,red ,blue & yellow)
black --l1 fuse
red-- l2 fuse
blue--l3 fuse
yellow -- earth to henley block

thus feeds a 3phase board in workshop
No neutral to it.

1..???? is why is there no neutral to it
its not connected to earth
swa at cu is bonded at the armourings back to earth connection in board
and not at tpn ( discrimination)

2..??? why does all the 3phase equipment still work without a neutral

i am having to update a single phase cu to a 6 way to accomodate a solar pv 9.9kw system
luckily its got a 10.mm feed to it.

thanks
jon

ballanced loads mate...motors.

however...just looking at what you have decribed as L1 L2 & L3...

since when has L1 been black?

 

[jon jordan]

no neutral connected in db though

 

[Knobhead]

A 3Ph machine doesn't need a neutral.

 

[MDJ]

no neutral connected in db though

the neutral is in the house db, I suspect the workshop doesn't need one as the kit doesn't need a neutral

 

[GLENNSPARK]

it should be

red=L1

Yellow=L2

Blue=L3

so something not right here...unless its just a case of someone not following the colours...or a phase reversal at the intake...

have you done a phase rotation on it?

 

[R G]

Looks like the 3 phase supply was installed just for 3 phase machines/motors ,( no neutral required on 3 phase motors )

The 4 core swa is not wired correctly , but I suspect it tallies at both ends also,,

 

[jon jordan]

how do i upload pics from i phone to here

 

[jon jordan]

arhh ok
equipment is laiths n drill presses
so these dont need a neutral
thanks that would explain y no neutral to cu then

live & learn

 

[Badged01]

You got there in the end ......

 

[Knobhead]

Thank god someone has learnt something today.

 

[jon jordan]

i needed a 3 circuits for solar pv
so i couldnt use the 3ph board as no neutral supplied
inside cu was a bit messy lol
thanks for replys guys understand it better now

 

[wozz]

Any lights in the workshop?

 

[Badged01]

You beat me to it! Was just about to ask how sockets/lights work there?

 

[wozz]

You beat me to it! Was just about to ask how sockets/lights work there?

Just keeping you on your toes :wink_smile:

 

[Badged01]

Just keeping you on your toes :wink_smile:

I need it or I can get carried away with my own importance. I've often been accused of being a legend in my own lunch hour!

 

[jon jordan]

theres a sub feed from house cu to a workshop single phase to power lights sockets
ta
jon

- - - Updated - - -

theres a sub feed from house cu to a workshop single phase to power lights sockets
ta
jon

 

[ipf]

Seems somebody went about the initial job in a strange sort of way....

 

[R G]

It looks like there was an original single phase supply , and then had 3 phase installed at a latter date, you see this a lot ,,,