The overfluxing value (V/f) is monitored to determine whether it exceeds the set threshold. When the overfluxing value exceeds this threshold the P632 will determine the tripping time according to the overfluxing magnitude value and the set characteristic.

The variable-time tripping characteristic is set by defining 12 pairs of overfluxing values and their associated tripping time values. Intermediate values are obtained by interpolation. The setting of the characteristic is checked for plausibility with regard to a monotonically decreasing characteristic. With values of V/f > 1.6 the tripping time is limited to the value set for V/f = 1.6. The tripping characteristic with default setting values is displayed in Fig. 3-148.

After a starting, the elapsed starting time is accumulated in a buffer. When the starting drops out, the buffer memory is discharged. The discharge gradient is defined by the set cooling time. When the starting recurs the buffer memory is again accumulated with starting time values. If the accumulated starting time reaches the tripping time value determined by the P632 then the trip signal will be issued. The buffer memory content during an interrupted starting is shown in Fig. 3-149. In case A, the tripping time determined by the P632 is not reached by the accumulated starting time. In case B, on the other hand, a trip signal is issued.