RCBO energy consumption

[John-SJW]

RCBOs consume between 1.5 and 2.5 watts for each pole - according to Wylex. Have a CU with largish bank of DP RCBOs then the annual cost of just having RCBOs is substantial. It is not just a few quid a year in electricity costs to have them. My question is:

Do RCBOs still consume electricity when switched off?

 

[newfutile]

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.

 

[John-SJW]

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.

 

[John-SJW]

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.

 

[pc1966]

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.

 

[timhoward]

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.

 

[davesparks]

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.

 

[timhoward]

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.

 

[John-SJW]

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.

 

[ipf]

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........

 

[timhoward]

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...

 

[ipf]

I've just had to replace a Miliwauke drill, so I'm on the deep fried spam for the rest of the month...

'What made Milwaukee famous.....has made a loser out of me ?

 

[ipf]

'What made Milwaukee famous.....has made a loser out of me ?

Better be careful, off thread a bit, although that song is about a kind of consumption.

 

[littlespark]

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.

Oh don’t….

You’re giving me student night flash backs…

 

[DPG]

I really do love how John tries to twist wording to make his incorrect comments appear to be factual. Fascinating. I'm not sure why though. Is there a point to doing this?

 

[mainline]

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.