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You should size your mcb to the correct one to protect the circuit, or am I missing your point?


Let’s say a standard new board with maybe 10 rcbo’s (not thinking AFDD yet) Nothing extreme load like a weed farm, but normal…. How much heat generated? How much power consumption? And would say a half module blank between each one would help?
A 1.00mm LED lighting circuit can use a 3A MCB, as the current draw will not get near to 3A. My LED lighting circuit draws 1.3 A max - I used an amp clamp with all lights on. Using a 6A mcb would reduce the possibility of a warmish MCB/RCBO and still protect the cable, one of its two prime functions. I always try to fit MCB/RCBO/fuses as low a value as possible, to give added protection in fault conditions on connected appliances.

The specs for MCB and RCBO energy consumption were posted by Aron B. Good idea, I did think of spacing out RCBOs to dissipate heat, if there is enough space in the CU. Unfortunately I have no surplus ways.
 
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The specs for MCB and RCBO energy consumption were posted by Aron B. Good idea, I did think of spacing out RCBOs to dissipate heat, if there is enough space in the CU. Unfortunately I have no surplus ways.
It would just be the mcb dissipating the heat better. The heat will still be produced. You might be thankful for a bit of heat next month...
 
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I heard about people using bitcoin mining rigs as a source of heating. I'm not sure about now

It would just be the mcb dissipating the heat better. The heat will still be produced. You might be thankful for a bit of heat next month...
Heat I have purchased . But heat when I do not need heat. :)
 
You should size your mcb to the correct one to protect the circuit, or am I missing your point?


Let’s say a standard new board with maybe 10 rcbo’s (not thinking AFDD yet) Nothing extreme load like a weed farm, but normal…. How much heat generated? How much power consumption? And would say a half module blank between each one would help?
I've no doubt that blanks may help to dissipate some heat, but I don't think I will be fitting a CU with twice the ways just to get some space between them, I shall stick to what I've been doing for years with no problems.

And as for sizing, I shall stick to Regulation 433.1.1
 
Heat I have purchased . But heat when I do not need heat. :)
If it's a concern, oversize all the cables.

Edit: oh I forgot you won't do that, as in another thread you argue for smaller ones.
 
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Do RCBOs still consume electricity when switched off?
I suspect I may regret this, but I will attemt to answer your original question..

From a scan of published block schematics of RCBO's, and John Wards teardown of a compact Hager (below), power for the electronics appears to come from 'switched live' - ie is disconnected when breaker 'off'.
My conclusion is that the answer to your question is "no".

I want to know how they work.
Might help if you have 21 minutes to spare! (the viewers comments are also useful)
 
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I suspect I may regret this, but I will attemt to answer your original question..

From a scan of published block schematics of RCBO's, and John Wards teardown of a compact Hager (below), power for the electronics appears to come from 'switched live' - ie is disconnected when breaker 'off'.
My conclusion is that the answer to your question is "no".

I want to know how they work.
Might help if you have the time!
I did conclude that. I also did post the same John Ward vid. ;)

Great vid by John Ward. Big Clive tears a Hager down that had fried. Worth looking at.
 
Unless they have changed the design, the Wylex ones are not completely off when open. I remember IR testing the busbar of my own board and found they have a hundred or kOhm still. However, I don't know if that is the main powering sources or not (i.e. if switching on changes it).

The Harger RCCB I have tried seem to IR open on both sides, so I guess they use a capacitive divider. That should be more energy-efficient than just a resistive divider but I don't have a spare Wylex RCBO to test those theories out.
 
I've only skim read this thread, but it looks as though this video might be relevant:
(they also measure some RCBOs, neons, and USB sockets from memory)

 
I always try to fit MCB/RCBO/fuses as low a value as possible, to give added protection in fault conditions on connected appliances.
But at #49 you say "Which brings me to the point of using the highest mcb rating you can to reduce the bi-metal strip bending consuming energy and getting warm"

In Other posts, you complain about loss, but you say you use the smallest cable you can get away with.

Small/Large Thick/thin which is it because you seem very confused.
 
But at #49 you say "Which brings me to the point of using the highest mcb rating you can to reduce the bi-metal strip bending consuming energy and getting warm"

In Other posts, you complain about loss, but you say you use the smallest cable you can get away with.

Small/Large Thick/thin which is it because you seem very confused.
Given chance he would argue with himself and I'm sure he did in a thread a little while ago
 
That Efixx video was useful, even at double the originally measured cost it seems the RCBO is only using around £1/year so less than depreciation if you assume a 10 year period for them and as-new cost of around £20 (and given the cost of AFDD well below their depreciation cost).

What was also said at the end of the video was about much higher usage on "stand by" like the speaker with Alexa, managing to simultaneously steal your money and privacy!

From memory by VM router/modem takes about 6W so is more like £20 per year and way more than my CU.
 
Will we all be going back to speccing' split boards now as more energy efficient in line with Appendix 17 of BBB?
 
But at #49 you say "Which brings me to the point of using the highest mcb rating you can to reduce the bi-metal strip bending consuming energy and getting warm"

In Other posts, you complain about loss, but you say you use the smallest cable you can get away with.

Small/Large Thick/thin which is it because you seem very confused.
You have poor comprehension. Read what I wrote again. It was clear enough.
 
I've only skim read this thread, but it looks as though this video might be relevant:
(they also measure some RCBOs, neons, and USB sockets from memory)

Excellent vid. Even Big Clive commented in comments section. They pointed to another vid at Lewden testing AFDDs. AFDDs combine four fault protectors in one unit. The longevity of AFDDs maybe in question they have complex electric boards inside, unles you pay a fortune for the top quality makes. But you can get around the AFDD regs by installing a ring final circuits supplying sockets, with 4mm cable and a 40A RCBO/MCB.
 
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But you can get around the AFDD regs by installing a ring final circuits supplying sockets, with 4mm cable and a 40A RCBO/MCB.

No you can't, for installations where AFDDs are required they are to be installed for all circuits supplying socket outlets rated at 32A or less. It is the rating of the socket outlet which is 32A or less, not the rating of the circuit.
 
But you can get around the AFDD regs by installing a ring final circuits supplying sockets, with 4mm cable and a 40A RCBO/MCB.
Additionally, a ring final circuit is defined in t'regs as having a 30 or 32 amp protective device:

433.1.204
Accessories to BS1363 may be supplied through a ring final circuit, with or without unfused spurs protected by a 30A or 32A protective device complying with BS88 / BS3036/ BS EN 60898 / BS EN 61009 etc.

If we went back to 14th edition things were a bit different then.
 
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That Efixx video was useful, even at double the originally measured cost it seems the RCBO is only using around £1/year so less than depreciation if you assume a 10 year period for them and as-new cost of around £20 (and given the cost of AFDD well below their depreciation cost).

What was also said at the end of the video was about much higher usage on "stand by" like the speaker with Alexa, managing to simultaneously steal your money and privacy!

From memory by VM router/modem takes about 6W so is more like £20 per year and way more than my CU.
52p per ann. to run a neon light, which will be approaching a £1 now energy has risen. Have three and £3 per ann. With all the rest of the standing losses in the hosue and in the CU you can pay for a night out. Add all this up over a whole nation and maybe a fossil fuel power station feeds it.
 
52p per ann. to run a neon light, which will be approaching a £1 now energy has risen. Have three and £3 per ann. With all the rest of the standing losses in the house and in the CU you can pay for a night out.
Either you have a massive CU full of circuits, or you live somewhere incredibly cheap!

Even up here in Dundee, which is hardly known for affluence, I won't get much of a night out on the £5 of my flat's always-on RCBOs.
 
I recently measured Arc Fault Detection Device and RCBO’s for stand by current , each one measured less than 3 mA . this was switched on with no load on the device(s).

these were all MCG devices.
 
A ring final circuit is defined in t'regs as having a 30 or 32 amp protective device:

433.1.204
Accessories to BS1363 may be supplied through a ring final circuit, with or without unfused spurs protected by a 30A or 32A protective device complying with BS88 / BS3036/ BS EN 60898 / BS EN 61009 etc.

If we went back to 14th edition things were a bit different then.
On a ring final circuit the cable current rating cannot be less than 2/3 (67%) of the MCB/RCBO rating. So, keeping this ratio, scaling up, a 40A RCBO/MCB, needs a cable current rating of 26.8A min, so 4mm cable is suitable as it is rated safely at 32A current capacity. So, installing a 4mm cable final ring circuit supplying socket-outlets, protected by a 40A RCBO/MCB is fine.

The reg relating to AFDDs says:
421.1.7:
"AC final circuits supplying socket-outlets with a rated current not exceeding 32 A"

That where an AFDD comes into the frame such as in a block of flats 6 floors or higher, care home, etc. So an AFDD needs to be fitted on radial or ring final circuits that have socket-outlets 32A protected and less. That is clear. The passage is clear that a ring final circuit above 32A does not need an AFDD.
 
Either you have a massive CU full of circuits, or you live somewhere incredibly cheap!

Even up here in Dundee, which is hardly known for affluence, I won't get much of a night out on the £5 of my flat's always-on RCBOs.
I mention all the devices in the house and inside the CU.
 
The reg relating to AFDDs says:
421.1.7:
"AC final circuits supplying socket-outlets with a rated current not exceeding 32 A"

That where an AFDD comes into the frame such as in a block of flats 6 floors or higher, care home, etc. So an AFDD needs to be fitted on radial or ring final circuits that have socket-outlets 32A protected and less. That is clear. The passage is clear that a ring final circuit above 32A does not need an AFDD.
Wrong. Those sockets are rated at 13A so they need protection as <= 32A.
 
I won't get much of a night out on the £5 of my flat's always-on RCBOs.
You just have no idea how to party. Battered Sausage and chips (£3.10), some gin and tonic flavour jelly from morrisons (£0.89), washed down with some 4Trade White Spirit from City Plumbing (£1.46)...ooops I went 45p over budget.
 
The reg relating to AFDDs says:
421.1.7:
"AC final circuits supplying socket-outlets with a rated current not exceeding 32 A"

So an AFDD needs to be fitted on radial or ring final circuits that have socket-outlets 32A protected and less.

It is not 32A protection, it is socket outlets rated at 32A or less.

It is describing the current rating of the socket outlet, not the rating of the protective device. You are misunderstanding the regulation as it is written.

If the regulation had included comma's like this:

AC final circuits, supplying socket-outlets, with a rated current not exceeding 32 A

then it would have the meaning you describe, but it does not.
 
On a ring final circuit the cable current rating cannot be less than 2/3 (67%) of the MCB/RCBO rating
I think that text was last seen in A.33 in the 14th edition. So while true once, I don't think it still is (unfortunately). By 16th edition it's explicitly 30 /32 A protective devices.
 
It is not 32A protection, it is socket outlets rated at 32A or less.

It is describing the current rating of the socket outlet, not the rating of the protective device. You are misunderstanding the regulation as it is written.
I think you have it Dave.
 
You just have no idea how to party. Battered Sausage and chips (£3.10), some gin and tonic flavour jelly from morrisons (£0.89), washed down with some 4Trade White Spirit from City Plumbing (£1.46)...ooops I went 45p over budget.
Let you off for less than 10%, then......with the money saved on the 'neon' lights.
I knew there'd be some tight sods reading this thread........😉
 
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Let you off for less than 10%, then......with the money saved on the 'neon' lights.
I knew there'd be some tight sods reading this thread........😉
I've just had to replace a Miliwauke drill, so I'm on the deep fried spam for the rest of the month...
 
Excellent vid. Even Big Clive commented in comments section. They pointed to another vid at Lewden testing AFDDs. AFDDs combine four fault protectors in one unit. The longevity of AFDDs maybe in question they have complex electric boards inside, unles you pay a fortune for the top quality makes. But you can get around the AFDD regs by installing a ring final circuits supplying sockets, with 4mm cable and a 40A RCBO/MCB.
You remind me of someone ????

I used to visit a friend who lived way out in the country, the fella you remind me of used to sit on a wall as you entered the village, he always had a piece of straw in his mouth.
Now what did the locals call him, damn I can't remember, but it will come to me.
 
It is not 32A protection, it is socket outlets rated at 32A or less.

It is describing the current rating of the socket outlet, not the rating of the protective device. You are misunderstanding the regulation as it is written.

If the regulation had included comma's like this:

AC final circuits, supplying socket-outlets, with a rated current not exceeding 32 A

then it would have the meaning you describe, but it does not.
Why bother educating him.
 
The loonies are here in force again. Amusing indeed.
That is one hell of an admission surprised it took you so long recognise it, I can only assume you have been reading back through your innane past posts
 
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