AJJewsbury:
Something must have been lost in the translation.
Testing at 250mA would not be RCD x 5, would it?
That's the point - it seems the standards have changed so that 5x IΔn is no longer the requirement. You might have noticed that all the requirements for a 30mA RCD used for additional protection to have 'an operating time not exceeding 40ms at a residual current of 5 IΔn' vanished completely from the 18th Ed - the requirement is simply for a 30mA RCD now. We seem to be discovering why....
I'm trying to imagine why such a change would have been thought a good idea - after all we certainly have the technology to achieve 40ms at 150mA - maybe it's to allow the RCD to ignore the sort of transients that can lead to 'unwanted tripping' or some such.
AJJewsbury:
Something must have been lost in the translation.
Testing at 250mA would not be RCD x 5, would it?
That's the point - it seems the standards have changed so that 5x IΔn is no longer the requirement. You might have noticed that all the requirements for a 30mA RCD used for additional protection to have 'an operating time not exceeding 40ms at a residual current of 5 IΔn' vanished completely from the 18th Ed - the requirement is simply for a 30mA RCD now. We seem to be discovering why....
I'm trying to imagine why such a change would have been thought a good idea - after all we certainly have the technology to achieve 40ms at 150mA - maybe it's to allow the RCD to ignore the sort of transients that can lead to 'unwanted tripping' or some such.
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