Welwyn W22 resistors

[Alistair D]

I always thought that the rated voltage was partly related to what the resistor could withstand after failure. In the case of a WW resistor the gap between the damaged ends of the winding could be very small and could even be carbonised. Perhaps not so much in the case of vitreous coated resistors but the gap between the windings either side of the burn out will also limit the max voltage that can be applied.

Al