I know it's not true but based on that reg alone it states :
Basic Protection
Persons and livestock shall be protected against dangers that may arise from contact with live parts of the installation.
This protection can be achieved by one of the following methods:
Preventing a current...
Can the above method alone be classed as basic protection according to 131.2.1 it can. Based on that regulation you can leave live terminals exposed if supplied by a 30mA RCD
A lot of these mock exam questions are not specific about armoured or non armoured multicore cables, flat twin or not etc, the correct table to use can be a bit of trial and error until you get the correct answer for Volt drop for example.
Why does this regulation refer you to regulation 415.1 rather than just stating 30mA RCD, this is one bit about the regs that confuses me, sometimes it's direct and consise, and other times it refers to another reg. why?
Ohhh I see so by minimum they are talking what's the minimum that will do the job, the wording is bad it should say calculate the minimum required capacity live conductor current for the circuit.
Good stuff find device rating divide by factors, look up increased calculated current against correct table and check install method column choose nearest highest value. Then worry about volt drop
28. Which one of the following is not considered when calculating the minimum current carrying capacity of live
conductors of a cable?
a Ambient temperature.
b Grouping.
c Type of protective device.
d The maximum permitted volt drop.
Is as though they're trying to be clever would be better to ask what other methods could be included, but the way I read it is you have an RCD at the board and they are now asking how do you create fault protection for your circuit, which you have no idea about location of or what it's for
A good memory trick for exam conditions for coordination
Ib In Iz
(Alphabet) the earlier letters are always lower in value than the earlier ones, saves remembering
Ib < In
In < Iz
Ib < Iz
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