I'd be grateful for any help with distributing the loads between the
two RCCBs on my 7th edition consumer unit.

I have:
1 radial upstairs lighting
1 radial downtairs lighting
1 upstairs ring main
1 downstairs ring main
1 kitchen ring main
1 radial oven circuit
1 shower circuit 10kW

On Aug 24, 9:15*am, wrote:
I'd be grateful for any help with distributing the loads between the
two RCCBs on my 7th edition consumer unit.

I have:
1 radial upstairs lighting
1 radial downtairs lighting
1 upstairs ring main
1 downstairs ring main
1 kitchen ring main
1 radial oven circuit
1 shower circuit 10kW

I expect 7th ed. had knife switches, not RCCBs.

On Aug 24, 10:45*am, Phil wrote:
On Aug 24, 9:15*am, wrote:

I'd be grateful for any help with distributing the loads between the
two RCCBs on my 7th edition consumer unit.

I have:
1 radial upstairs lighting
1 radial downtairs lighting
1 upstairs ring main
1 downstairs ring main
1 kitchen ring main
1 radial oven circuit
1 shower circuit 10kW

I expect 7th ed. had knife switches, not RCCBs.

Ah yes Phil I missed the 1 off! Now anything constructive to add?

On 24/08/2011 09:15, wrote:
I'd be grateful for any help with distributing the loads between the
two RCCBs on my 7th edition consumer unit.

What is the maximum current load on the RCDs?

The usual approach with only two RCDs is to mix the downstairs lighting
with upstairs sockets:

I have:

RCD1

1 radial downtairs lighting
1 upstairs ring main

I would put the kitchen ring on this one so that you have a way of
isolating sockets downstairs but still having power available.

1 kitchen ring main

Keep the oven with it

1 radial oven circuit

RCD2

1 radial upstairs lighting
1 downstairs ring main

Which leaves the shower here

1 shower circuit 10kW



--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

On Aug 24, 11:29*am, John Rumm wrote:
On 24/08/2011 09:15, wrote:

I'd be grateful for any help with distributing the loads between the
two RCCBs on my 7th edition consumer unit.

What is the maximum current load on the RCDs?

The usual approach with only two RCDs is to mix the downstairs lighting
with upstairs sockets:

I have:

RCD1

1 radial downtairs lighting
1 upstairs ring main

I would put the kitchen ring on this one so that you have a way of
isolating sockets downstairs but still having power available.

1 kitchen ring main

Keep the oven with it

1 radial oven circuit

RCD2

* 1 radial upstairs lighting
* 1 downstairs ring main

Which leaves the shower here

* 1 shower circuit 10kW

--
Cheers,

John.

/================================================== ===============\
| * * * * *Internode Ltd - *http://www.internode.co.uk* * * * * *|
|-----------------------------------------------------------------|
| * * * *John Rumm - john(at)internode(dot)co(dot)uk * * * * * * *|
\================================================= ================/



Thanks for that John. However I don't think I can put the oven on the
kitchen ring as all the wire sizing guides I have seen require more
than 2.5mm T&EI
Also I'm not sure having the shower and the upstairs lighting on the
same RCCB is wise as if the lighting goes it leaves you in the shower
in the dark.

John Rumm wrote:
On 24/08/2011 09:15, wrote:
I'd be grateful for any help with distributing the loads between the
two RCCBs on my 7th edition consumer unit.

What is the maximum current load on the RCDs?

The usual approach with only two RCDs is to mix the downstairs
lighting with upstairs sockets:

I have:

RCD1

1 radial downtairs lighting
1 upstairs ring main

I would put the kitchen ring on this one so that you have a way of
isolating sockets downstairs but still having power available.

1 kitchen ring main

Keep the oven with it

1 radial oven circuit

RCD2

1 radial upstairs lighting
1 downstairs ring main

Which leaves the shower here

1 shower circuit 10kW


I'd do the same apart from the oven. I would put it with the downstairs ring
and upstairs lights.Although is probably does not matter.

I would put the shower on a different RCD to the boiler (whatever circuit
that is connected to).

--
Adam

wrote:
On Aug 24, 11:29 am, John Rumm wrote:
On 24/08/2011 09:15, wrote:

I'd be grateful for any help with distributing the loads between the
two RCCBs on my 7th edition consumer unit.

What is the maximum current load on the RCDs?

The usual approach with only two RCDs is to mix the downstairs
lighting with upstairs sockets:

I have:

RCD1

1 radial downtairs lighting
1 upstairs ring main

I would put the kitchen ring on this one so that you have a way of
isolating sockets downstairs but still having power available.

1 kitchen ring main

Keep the oven with it

1 radial oven circuit

RCD2

1 radial upstairs lighting
1 downstairs ring main

Which leaves the shower here

1 shower circuit 10kW

--
Cheers,

John.

/================================================== ===============\
Internode Ltd - http://www.internode.co.uk |
-----------------------------------------------------------------|
John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/



Thanks for that John. However I don't think I can put the oven on the
kitchen ring as all the wire sizing guides I have seen require more
than 2.5mm T&EI

I believe he meant put to the oven MCB on the same RCD side as the kitchen
ring.

Also I'm not sure having the shower and the upstairs lighting on the
same RCCB is wise as if the lighting goes it leaves you in the shower
in the dark.

It does not matter. If the RCD for the lights trip whilst you are in the
shower then you are going to be in the dark in the shower! One way leaves
the water running the other stops the water!


--

Adam

On 24/08/2011 11:43, wrote:
On Aug 24, 11:29 am, John wrote:
On 24/08/2011 09:15, wrote:

I'd be grateful for any help with distributing the loads between the
two RCCBs on my 7th edition consumer unit.

What is the maximum current load on the RCDs?

The usual approach with only two RCDs is to mix the downstairs lighting
with upstairs sockets:

I have:

RCD1

1 radial downtairs lighting
1 upstairs ring main

I would put the kitchen ring on this one so that you have a way of
isolating sockets downstairs but still having power available.

1 kitchen ring main

Keep the oven with it

1 radial oven circuit

RCD2

1 radial upstairs lighting
1 downstairs ring main

Which leaves the shower here

1 shower circuit 10kW


Thanks for that John. However I don't think I can put the oven on the
kitchen ring as all the wire sizing guides I have seen require more
than 2.5mm T&EI

I was not suggesting changing the wiring - just placing your oven
circuit on the same partition of the CU as the kitchen ring.

Also I'm not sure having the shower and the upstairs lighting on the
same RCCB is wise as if the lighting goes it leaves you in the shower
in the dark.


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

On Wed, 24 Aug 2011 01:15:39 -0700 (PDT),
wrote:

I'd be grateful for any help with distributing the loads between the
two RCCBs on my 7th edition consumer unit.

I have:
1 radial upstairs lighting
1 radial downtairs lighting
1 upstairs ring main
1 downstairs ring main
1 kitchen ring main
1 radial oven circuit
1 shower circuit 10kW

I am not an electrician but have just had a new consumer unit
installed by an electrician.

The way we did it was to have an individual RCBO for every circuit.
That means a trip on one circuit will only affect that circuit.
http://www.screwfix.com/p/crabtree-6...rve-rcbo/75542

Scott wrote:

I am not an electrician but have just had a new consumer unit
installed by an electrician.

The way we did it was to have an individual RCBO for every circuit.
That means a trip on one circuit will only affect that circuit.

But at a cost. How much did that set you back?


--
Adam

On Wed, 24 Aug 2011 20:07:18 +0100, "ARWadsworth"
wrote:

Scott wrote:

I am not an electrician but have just had a new consumer unit
installed by an electrician.

The way we did it was to have an individual RCBO for every circuit.
That means a trip on one circuit will only affect that circuit.

But at a cost. How much did that set you back?

£590 (for nine RCBOs).

Scott wrote:
On Wed, 24 Aug 2011 20:07:18 +0100, "ARWadsworth"
wrote:

Scott wrote:

I am not an electrician but have just had a new consumer unit
installed by an electrician.

The way we did it was to have an individual RCBO for every circuit.
That means a trip on one circuit will only affect that circuit.

But at a cost. How much did that set you back?

£590 (for nine RCBOs).

That's not a bad price. What make was it?

--
Adam

On Wed, 24 Aug 2011 21:34:01 +0100, "ARWadsworth"
wrote:

Scott wrote:
On Wed, 24 Aug 2011 20:07:18 +0100, "ARWadsworth"
wrote:

Scott wrote:

I am not an electrician but have just had a new consumer unit
installed by an electrician.

The way we did it was to have an individual RCBO for every circuit.
That means a trip on one circuit will only affect that circuit.

But at a cost. How much did that set you back?

£590 (for nine RCBOs).

That's not a bad price. What make was it?

Crabtree. The price covered parts and labour. AIUI you would require
eight RCBOs so yours could be slightly cheaper.

Once the electrician got over his initial surprise (I nearly said
shock!) he agreed it was the 'way to go'. I just like the idea that
if the washing machine goes faulty it won't cause the computer to
crash.

On Aug 24, 9:40*pm, Scott wrote:
On Wed, 24 Aug 2011 21:34:01 +0100, "ARWadsworth"



wrote:
Scott wrote:
On Wed, 24 Aug 2011 20:07:18 +0100, "ARWadsworth"
wrote:

Scott wrote:

I am not an electrician but have just had a new consumer unit
installed by an electrician.

The way we did it was to have an individual RCBO for every circuit.
That means a trip on one circuit will only affect that circuit.

But at a cost. How much did that set you back?

£590 (for nine RCBOs).

That's not a bad price. What make was it?

Crabtree. *The price covered parts and labour. *AIUI you would require
eight RCBOs so yours could be slightly cheaper.

Once the electrician got over his initial surprise (I nearly said
shock!) he agreed it was the 'way to go'. *I just like the idea that
if the washing machine goes faulty it won't cause the computer to
crash.

I agree that it's nice to have that protection individually for each
circuit but cost wise it's not comparable.
My 17th ed. consumer unit with two RCCB and 10 MCB cost about £60!

On Aug 25, 8:43*am, wrote:
On Aug 24, 9:40*pm, Scott wrote:









On Wed, 24 Aug 2011 21:34:01 +0100, "ARWadsworth"

wrote:
Scott wrote:
On Wed, 24 Aug 2011 20:07:18 +0100, "ARWadsworth"
wrote:

Scott wrote:

I am not an electrician but have just had a new consumer unit
installed by an electrician.

The way we did it was to have an individual RCBO for every circuit..
That means a trip on one circuit will only affect that circuit.

But at a cost. How much did that set you back?

£590 (for nine RCBOs).

That's not a bad price. What make was it?

Crabtree. *The price covered parts and labour. *AIUI you would require
eight RCBOs so yours could be slightly cheaper.

Once the electrician got over his initial surprise (I nearly said
shock!) he agreed it was the 'way to go'. *I just like the idea that
if the washing machine goes faulty it won't cause the computer to
crash.

I agree that it's nice to have that protection individually for each
circuit but cost wise it's not comparable.
My 17th ed. consumer unit with two RCCB and 10 MCB cost about £60!

We were thinking about RCBO(s) to protect the fridge and freezer from
defrosting if a trip happened while we were away.

But the cost of the RCBO(s) was more than the value of food in the
fridge, and comparable to the value of food in the (upright) freezer.
Considering it had never been a problem before, this seemed rather an
expensive "insurance policy" for such a low risk and low value event.

To cover the potential lack of light when a light blows, an MCB and/or
RCD trips, or there's a power cut, or I intentionally switch off the
circuit(s), I added emergency lights in the hall.

Cheers,
David.

The way we did it was to have an individual RCBO for every circuit.
That means a trip on one circuit will only affect that circuit.


Once the electrician got over his initial surprise (I nearly said
shock!) he agreed it was the 'way to go'. I just like the idea that
if the washing machine goes faulty it won't cause the computer to
crash.

My neighbour lost the contents of his freezer and a pondful of coy carp when
a light bulb blew in an outside light while he was away on holiday.
--
Chris R

wrote:
On Aug 24, 9:40 pm, Scott wrote:
On Wed, 24 Aug 2011 21:34:01 +0100, "ARWadsworth"



wrote:
Scott wrote:
On Wed, 24 Aug 2011 20:07:18 +0100, "ARWadsworth"
wrote:

Scott wrote:

I am not an electrician but have just had a new consumer unit
installed by an electrician.

The way we did it was to have an individual RCBO for every
circuit. That means a trip on one circuit will only affect that
circuit.

But at a cost. How much did that set you back?

£590 (for nine RCBOs).

That's not a bad price. What make was it?

Crabtree. The price covered parts and labour. AIUI you would require
eight RCBOs so yours could be slightly cheaper.

Once the electrician got over his initial surprise (I nearly said
shock!) he agreed it was the 'way to go'. I just like the idea that
if the washing machine goes faulty it won't cause the computer to
crash.

I agree that it's nice to have that protection individually for each
circuit but cost wise it's not comparable.
My 17th ed. consumer unit with two RCCB and 10 MCB cost about £60!

There is the inbetween option. RCBOs for a couple of circuits and the two
RCDs for the rest of the circuits. Probably adds £50 to the installation. I
use such setups when there are dedicated outdoor circuits.

--
Adam

On 25/08/2011 17:53, ARWadsworth wrote:
wrote:
On Aug 24, 9:40 pm, wrote:
On Wed, 24 Aug 2011 21:34:01 +0100, "ARWadsworth"



wrote:
wrote:
On Wed, 24 Aug 2011 20:07:18 +0100, "ARWadsworth"
wrote:

wrote:

I am not an electrician but have just had a new consumer unit
installed by an electrician.

The way we did it was to have an individual RCBO for every
circuit. That means a trip on one circuit will only affect that
circuit.

But at a cost. How much did that set you back?

£590 (for nine RCBOs).

That's not a bad price. What make was it?

Crabtree. The price covered parts and labour. AIUI you would require
eight RCBOs so yours could be slightly cheaper.

Once the electrician got over his initial surprise (I nearly said
shock!) he agreed it was the 'way to go'. I just like the idea that
if the washing machine goes faulty it won't cause the computer to
crash.

I agree that it's nice to have that protection individually for each
circuit but cost wise it's not comparable.
My 17th ed. consumer unit with two RCCB and 10 MCB cost about £60!

There is the inbetween option. RCBOs for a couple of circuits and the two
RCDs for the rest of the circuits. Probably adds £50 to the installation. I
use such setups when there are dedicated outdoor circuits.

Yup, I was about to suggest the middle ground option... There are a
bunch of circuits that are highly unlikely to present trip hazards, and
others that are far moire likely. The unlikely ones can be distributed
about the pair of RCDs on the nominal "17th edition" (i.e. cheap 'n'
basic) CU, and then any likely problem circuits given RCBOs.


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

On 25/08/2011 13:27, Chris R wrote:
The way we did it was to have an individual RCBO for every circuit.
That means a trip on one circuit will only affect that circuit.


Once the electrician got over his initial surprise (I nearly said
shock!) he agreed it was the 'way to go'. I just like the idea that
if the washing machine goes faulty it won't cause the computer to
crash.

My neighbour lost the contents of his freezer and a pondful of coy carp when
a light bulb blew in an outside light while he was away on holiday.

Nicely illustrating why having outdoor circuits protected by the same
RCD as anything in the house is not a good policy.

--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

Scott wrote:
On Thu, 25 Aug 2011 00:43:50 -0700 (PDT),
wrote:

On Aug 24, 9:40 pm, Scott wrote:
On Wed, 24 Aug 2011 21:34:01 +0100, "ARWadsworth"



wrote:
Scott wrote:
On Wed, 24 Aug 2011 20:07:18 +0100, "ARWadsworth"
wrote:

Scott wrote:

I am not an electrician but have just had a new consumer unit
installed by an electrician.

The way we did it was to have an individual RCBO for every
circuit. That means a trip on one circuit will only affect that
circuit.

But at a cost. How much did that set you back?

£590 (for nine RCBOs).

That's not a bad price. What make was it?

Crabtree. The price covered parts and labour. AIUI you would require
eight RCBOs so yours could be slightly cheaper.

Once the electrician got over his initial surprise (I nearly said
shock!) he agreed it was the 'way to go'. I just like the idea that
if the washing machine goes faulty it won't cause the computer to
crash.

I agree that it's nice to have that protection individually for each
circuit but cost wise it's not comparable.
My 17th ed. consumer unit with two RCCB and 10 MCB cost about £60!

How long will it last? Say 20 years. £30 per year. 60p per week.
Quarter of a pint of beer. I bet you spend far more than that on
other non-essentials.

I would be cheaper had you DIYed it:-)

--
Adam