For a standard domestic Install, split board with 2x Type AC main switches.
No PV or Car Chargers should this be a C3 or C2?
Thanks in advance
For a standard domestic Install, split board with 2x Type AC main switches.
No PV or Car Chargers should this be a C3 or C2?
Thanks in advance
Yesterday's announcement from the Government: https://www.gov.uk/government/news/government-to-go-further-and-faster-in-becoming-energy-secure
If plug-in PV is being pushed as a way forward, and these are to have a UK standard plug (although BS 1363-1:2023 Clause 5 states that the UK plug shall not be used for connecting generators) then certainly in rented homes, and in flats (rented or otherwise), for the installation to be considered safe, surely:
1. RCDs (RCCBs and RCBOs) for socket-outlet circuits (and upstream distribution circuits if applicable) would have to be at least Type A (because of the way inverters operate, but also for the existing PV inverter standard BS EN 62109-1, this is stated as a requirement for 'pluggable type A' equipment (i.e.. with a standard plug) to be compatible with Type A RCDs; and
2. RCDs (RCCBs and RCBOs) for socket-outlet circuits (and upstream distribution circuits if applicable) would have to be bidirectional (Regulation 530.3.201 introduced in Amendment 3); and
3. RCDs (RCCBs and RCBOs) for socket-outlet circuits would have to disconnect all live conductors (see Regulation 551.7.1)?
product standard for balcony solar could mandate an RCD plug for example.
Agreed
product standard for balcony solar could mandate an RCD plug for example.
I think that's missed the point ... the RCD protecting other socket-outlets could be:
1. Blinded if it's Type AC
2. Permanently damaged by the presence of a source of energy on its load terminals if unidirectional.
THe danger is then a fault on other appliances connected in the same circuit. In the case of item 2 above, this will persist even after the plug-in generator is unplugged ... so I'm not sure how this could be addressed by the product or its instructions for use?
The average consumer will have no idea what sort of RCDs they have.
Neither will yer average politician.
They will be happy until something does happen, it's put forward that the RCD didn't operate and that might have saved a life ... and then all hell will break loose; and it will, of course, be our fault !
Given that in-service RCDs have a general failure rate something in the order of 7% ... aren't we in that situation anyway?
Likewise when the householder admits they haven't pressed the T button in the last 6 months...
- Andy.
Given that in-service RCDs have a general failure rate something in the order of 7% ...
Are we sure this statistic still current? Yes, I'm aware that, what is now quite a long time ago, there was a study that indicated that statistic ... but there have been a number of developments in product standards for RCDs over the past 25-30 years.
In fact, this site proposes 97 % reliable, with an improvement if the devices are tested regularly: https://www.electricalsafetyfirst.org.uk/guidance/safety-around-the-home/rcds-explained/
Compare that with certain unidirectional devices that are known to fail 100 % of the time if they are operated (including by pressing the test button) with a 230 V source connected to the load terminals ...
aren't we in that situation anyway?
So, no I don't think we are.
In fact, this site proposes 97 % reliable, with an improvement if the devices are tested
I really struggle with that. I suppose that it means that if RCDs are tested and are found to fail, they are replaced, which apparently improves the reliability overall.
3% failure rate. What would you accept for the brakes on your car, for example?
What would you accept for the brakes on your car, for example?
Surely there are far more [orders of magnitude more] injuries and deaths due to RTAs than electricity-related incidents?
Need I say more?
In fact, this site proposes 97 % reliable,
OK maybe 3% rather rather than 7% .. but the same point remains I think - we're already in a situation where an RCD may well not save a life when it was expected to. Someone may be called up to explain. The explanation may be entirely reasonable - nothing's 100% perfect - we do the best we can with the technology available and the limits of acceptable costs - the victim was part of the unfortunate 5% or so of the population that isn't fully protected by electrical theory, etc.
Ultimately is it worth upgrading probably millions of RCDs at a national cost of hundreds of millions if not billions of pounds, to achieve, not perfection, but merely something slightly less imperfect? Or would the money be better spent on some better returning safety measures?
- Andy.
Surely there are far more [orders of magnitude more] injuries and deaths due to RTAs than electricity-related incidents?
OK, bad analogy.
How about seatbelts? In the vast majority of journeys, they provide no restraint because none is required.
Is there any evidence that RCDs have saved lives over the past 40 - 50 years? Even if electrical fatalities have reduced, it could be for other reasons, so difficult to prove.
Compare that with certain unidirectional devices that are known to fail 100 % of the time if they are operated (including by pressing the test button) with a 230 V source connected to the load terminals ...
Just for clarity, the RCD part of a unidirectional RCBO may fail in such circumstances but will the mcb characteristic remain available?
Compare that with certain unidirectional devices that are known to fail 100 % of the time if they are operated (including by pressing the test button) with a 230 V source connected to the load terminals ...
Just for clarity, the RCD part of a unidirectional RCBO may fail in such circumstances but will the mcb characteristic remain available?
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