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 ,,,

 

[Badged01]

The mystery solved ........

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

and yes most definately .......

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

- - - Updated - - -

And further intrigue to the plot ........

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 ,,,

 

[ipf]

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 ,,,

Then they should have binned it and installed 3ph and N...but we might as well have a **** up.

 

[GLENNSPARK]

OK.

so i distinctly remember asking if a phase rotation had been carried out here

as
it is:

black --l1 fuse
red-- l2 fuse
blue--l3 fuse

and theres no identification rings then its a contravention of 514.3

 

[telectrix]

saturn's got all the rings: jupiter's got all the moons:and i ate all the pies. so there.

 

[Badged01]

......... and theres no identification rings then its a contravention of 514.3

A man after my own heart, quoting regs pulls the chicks ......

 

[R G]

Then they should have binned it and installed 3ph and N...but we might as well have a **** up.

Probably didn't want any disturbance to the lighting and power with the machines starting

 

[netblindpaul]

PV won't comply after he installs it either by the description here.

 

[jon jordan]

looks like a diy job to me the 3phase
BUT i wont be using the 3ph db
i shall be using the single phase board i will be making it a 6 way instead if the 3 way installed via 10 mm feed

1x 32 ring
1 x 6 amp lights
1 x 20amp to paint booth
3 x 16amps for pv

 

[netblindpaul]

See what I mean!

 

[Badged01]

See what I mean!

Nope, but Im sure you can enlighten us .......

 

[netblindpaul]

It seems 3ph PV system is being connected to 3x16A mcb's in a 1ph DB, which is not at the origin of the installation, thus downstream of some protective devices, thus negating the function of said protective devices, with regard to ADS and relying upon the PV inverter to undertake the disconnection.

What else do you want?

Do you think it's OK to skew the supply by 48A of PV? infeeeding to a single phase.
Will the DNO OK this, will it be OK, is it OK, what more.

I despair, I really do.

I really will not comment any more on this thread, so don't even bother to try to get me to.

 

[Badged01]

It took some teasing out but we eventually got there ..... now even I'm enlightened