whisky-dave wrote:

John Rumm wrote:

If the voltage sags too far, then you get lower PSCC so can expect
slower operation of protective devices under fault conditions, so
increase electrocution risk, and catastrophic cable failure risk.

But not in under 3 hours.

The 3 hours at 40+ Amps is the "slow" part of the MCB curve, in the
event of a short circuit you want sufficient current to ensure it trips
within the "fast" part of the curve ...