Coby:
If you simply read the 16th Edition you pick up the principle that I explained to you above.
When you read the Definitions section you become aware that there is still a problem with EEBADS, getting caught with a hazardous live conductor in one hand and an earthed conductive part in the other!
The authors were aware that RCD's were to expensive to insist on at the time, but they knew that EEBADS + RCD's was the answer to the problem. That explains why they used the definitions that they did, assuming that you would be smart enough to understand the basic principle described above!
EEBADS has absolutely nothing to do with RCD operation.
Consider a lawnmower outdoors in the garden, and you've cut through the lead.
Where is your equipotential bonding then?
Also, ADS doesn't operate either - because the cable and lawnmower were both Class II.
Which is why we do require RCDs for additional protection.
It's also worth considering the fact we are not really discussing BS 7671 here, but IEC 61140 (BS EN 61140) - which is the over-arching standard. This standard acknowledges there is context required for each of the protective measures (and limitations). What's achieved is considered to be what is reasonably practicable (or reduce risks to an as low as reasonably practicable level), not absolute protection.
Incidentally, there are limitations to the effectiveness of RCD protection as well.
Coby:
If you simply read the 16th Edition you pick up the principle that I explained to you above.
When you read the Definitions section you become aware that there is still a problem with EEBADS, getting caught with a hazardous live conductor in one hand and an earthed conductive part in the other!
The authors were aware that RCD's were to expensive to insist on at the time, but they knew that EEBADS + RCD's was the answer to the problem. That explains why they used the definitions that they did, assuming that you would be smart enough to understand the basic principle described above!
EEBADS has absolutely nothing to do with RCD operation.
Consider a lawnmower outdoors in the garden, and you've cut through the lead.
Where is your equipotential bonding then?
Also, ADS doesn't operate either - because the cable and lawnmower were both Class II.
Which is why we do require RCDs for additional protection.
It's also worth considering the fact we are not really discussing BS 7671 here, but IEC 61140 (BS EN 61140) - which is the over-arching standard. This standard acknowledges there is context required for each of the protective measures (and limitations). What's achieved is considered to be what is reasonably practicable (or reduce risks to an as low as reasonably practicable level), not absolute protection.
Incidentally, there are limitations to the effectiveness of RCD protection as well.
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