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Table 41.1 Assumed Touch Voltage
Former Community Member
I am a bit confused by this. Why do the disconnection times in Table 41.1 appear to be based on a touch voltage of 100 volts rather than a touch voltage of 125 volts?
For example, 110% of 230= 253 volts. Assuming L and PE are of the same size and material, indirect contact touch voltage is 126.5 volts. Would 0.33 seconds not appear more realistic?
"Sluggishly? With proper loop impedance an MCB will directly unlatch and open in 1.5 cycles. An RCD on the other hand must rely on unlatching a magnet, which then triggers a larger opening mechanism. Rather complex. It can jam. Any electronics can fail."
H.R.C. fuses can clear a fault in less than half a cycle.
When I test 30mA R.C.D.s at 5 X I delta n, I usually get an operating time of between 15 and 22 mS. Well within the 40mS most people expect.
"Sluggishly? With proper loop impedance an MCB will directly unlatch and open in 1.5 cycles. An RCD on the other hand must rely on unlatching a magnet, which then triggers a larger opening mechanism. Rather complex. It can jam. Any electronics can fail."
H.R.C. fuses can clear a fault in less than half a cycle.
When I test 30mA R.C.D.s at 5 X I delta n, I usually get an operating time of between 15 and 22 mS. Well within the 40mS most people expect.
