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ProMbrooke:
Thats where CPCs come in, in that they would cause the fuse or MCB to open in 0.2 seconds or less.
Doesn't that happen anyway ... in TN systems where the loop impedance ensures operation in 0.1 s?
The issue being, that, in TN-S systems (no RCD), you're limited in circuit length with Type C mcb's.
Also, interested where 25 V comes into the equation here? To do that, you've got to oversize the cpc, not undersize it ... and even then, may not be possible in TN-S due to the effect of the distributor's cpc ?
ProMbrooke:
Thats where CPCs come in, in that they would cause the fuse or MCB to open in 0.2 seconds or less.
Doesn't that happen anyway ... in TN systems where the loop impedance ensures operation in 0.1 s?
The issue being, that, in TN-S systems (no RCD), you're limited in circuit length with Type C mcb's.
Also, interested where 25 V comes into the equation here? To do that, you've got to oversize the cpc, not undersize it ... and even then, may not be possible in TN-S due to the effect of the distributor's cpc ?
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