Rcbo???

[Kev2632]

Im scratching my head here at this, its probably because of the time off night but i cant get my head round this at all, here in the picture is a contactor for the outside lights, now this is one of many contactors throughout the building. there is contactors at each consumer but there is 1 Photocell controlling everything,so all the contactors was linked out to bring them in at the same time. Now every circuit is on its own RCBO, you will notice that they have joined all the neutrals in a connectore block, wouldnt that affect the RCBOS? as they are all coming from different circuits??

 

[micknew]

Post deleted after reading again.

 

[Spudnik]

Interesting.

Surely it will only be the line's that go through the contactor?

 

[Kev2632]

Yea but what im meaning is you will see how they have all the neutrals joined together for the supplys and the control side of the contactor, but they are off different Circuits, so wont the RCBO trip as all the neutrals are connected together?

 

[Kev2632]

all of the neutrals would be connected together on the neutral bar anyway

So it doesnt matter if other neutrals are joined together with each other then?? where as if it was say like a split load RCD board and the neutrals were all joined together it would trip wouldnt it?

 

[Plonker 3]

all of the neutrals would be connected together on the neutral bar anyway EDIT sorry i thought it was the neutrals coming off the rcbo itself that were connected

Not when RCBOs are used they aren't.

 

[D80]

What is the actual fault/problem?

 

[Kev2632]

Not when RCBOs are used they aren't.

Im just trying to get my head round it grr its late haha, but i keep comparing the RCBO'S to like a split load RCD Board, why is it that you can connect all the neutrals together like that on RCBO's but if i was do something like that with a split RCD board it would trip the RCD because it sharing neutrals from a different RCD's??

 

[Plonker 3]

I think the problem here is that because it is controlled from a photocell everything switches on at the same time, so it is possible that the RCBO isnt sensing a imbalance in the conductors. The only time it would trip a RCBO is if there is something switched on and the other RCBO is receiving the neutral imbalance.

 

[nickblake]

Looking at the Picture there only appears to be 2 wires going into the Contactor what you may have is a single RCBO supplying the contactor and multiple circuits going from the contactor to the lights hence the reason why all the neutrals are joined ,looking at the picture it looks like a 3 phase board with the tripple pole being marked L1L2L3 , looking at the contactor again it looks like just one of the contacts is being used , it may be me as i shouldnt have gone to specsavers , what can be done is a Day light sensor having a low current capacity using a Contactor with a higher current rating , or am i totally looking at the worng pic

 

[Geoffsd]

The final circuit neutrals will have to be separated.

That's why they are connected to the top of the RCBOs and not to a neutral bar.

 

[Kev2632]

I think the problem here is that because it is controlled from a photocell everything switches on at the same time, so it is possible that the RCBO isnt sensing a imbalance in the conductors. The only time it would trip a RCBO is if there is something switched on and the other RCBO is receiving the neutral imbalance.

im having a stupid moment here to myself, sorry im not explaining myself properly

there is no fault with this photo,

All im trying too get my head round is, Why on RCBO can all the neutrals by connected together on the 1 neutral bar? wont the other RCBO see any imbalance from the other ones? because i know on a 240v Split load RCD board you cant share neutrals from other RCD'S so why can you connect all the neutrals together on RCBO'S?

 

[Des 56]

Being old and a little short of eagle eyed,I have difficulty seeing the detail in the picture
i will make a comment though

Are you sure its circuit neutrals that you believe you are seeing connector blocked ?
Its probable the contactors are switching the lives only and what you are seeing is the coil feed and neutrals in and then out to the next contactor, all these fed from one circuit down the line

 

[Kev2632]

Being old and a little short of eagle eyed,I have difficulty seeing the detail in the picture
i will make a comment though

Are you sure its circuit neutrals that you believe you are seeing connector blocked ?
Its probable the contactors are switching the lives only and what you are seeing is the coil feed and neutrals in and then out to the next contactor, all these fed from one circuit down the line

im having a stupid moment here to myself, sorry im not explaining myself properly

there is no fault with this photo,

All im trying too get my head round is, Why on RCBO can all the neutrals by connected together on the 1 neutral bar with there neutral lead? wont the other RCBO see any imbalance from the other ones? because i know on a 240v Split load RCD board you cant share neutrals from other RCD'S so why can you connect all the neutrals together on RCBO'S?

 

[Des 56]

The rcbos are likely to be single pole,the outgoing neutral will be the circuit load side
The feed neutrals of the rcbos are looped at the neutral bar
Where are you thinking that the neutrals are being grouped?

The neutrals have to go through the rcbo to maintain balance
If there are any parrallel paths for that neutral,it will imbalance

 

[Kev2632]

so why can you connect all the neutral leads to just 1 Neutral bar wont the affect the other RCBO's ?

 

[nickblake]

I see that makes sence now ,your flying lead of the neutral is the neutral the circuit neutral is connected to the electronics of the RCBO so balancing out the RCBO exactly as the Live is so realy its live and neutral in through the electronics then out if that make sence

 

[Kev2632]

I see that makes sence now ,your flying lead of the neutral is the neutral the circuit neutral is connected to the electronics of the RCBO so balancing out the RCBO exactly as the Live is so realy its live and neutral in through the electronics then out if that make sence

yea i understand what you mean,so in theory in relation to that photo then, there is no chance of the final circuits (NEUTRALS) being joined together in that connector block then? as there is two different RCBOs supplys there
that would trip it yea?

 

[nickblake]

Correct as before they hit the load side where its balanced it goes through the electronics ,its like a wall between the supply neutral and the load neutral if you connect 2 load neutrals together it will trip just like in dual RCD boards when you have a shared neutral

 

[Kev2632]

so basically your saying the Neutral LEAD is the supply neutral to each circuit then yea? it goes out on the live round the circuit and back through the neutral, through the electronics, and up the neutral lead yea? is that right?