With the P632, four independent parameter subsets may be pre-set. The user may switch between parameter subsets during operation without interrupting the protection function.

The control path determining the active parameter subset (function setting or binary signal input) may be selected via the function setting PSS: Control via USER or via the external signal PSS: Control via user EXT. Correspondingly, the parameter subset is selected either in accordance with the pre-set function setting PSS: Param.subs.sel. USER or in accordance with external signals. Which parameter subset is actually active at a particular time may be determined by scanning the logic state signals PSS: Actual param. subset or PSS: PS 1 active.

If the binary signal inputs are to be used for parameter subset selection, then the P632 first checks to determine whether at least two binary inputs are configured for parameter subset selection. If this is not the case, then the parameter subset selected via the function setting will be active. The P632 also checks whether the signals present at the binary signal inputs allow an unambiguous parameter subset selection. This is only true when only one binary signal input is set to a logic level of “1”. If more than one signal input is set to a logic level of “1”, then the parameter subset previously selected remains active. Should a dead interval occur while switching between parameter subsets (this is the case if all binary signal inputs have a logic level of “0”), then the stored hold time is started. While this timer stage is running, the previously selected parameter subset remains active. As soon as a signal input has a logic level of “1”, the associated parameter subset becomes active. If, after the stored time has elapsed, there is still no signal input with a logic level of “1”, the parameter subset selected via the function parameter becomes active.

If, after the supply voltage is turned on, no logic level of “1” is present at any of the binary signal inputs selected for the parameter subset selection, then the parameter subset selected via the function parameter will become active once the stored time has elapsed. The previous parameter subset remains active while the stored hold timer stage is running.

Parameter subset selection may also occur during a starting condition. When subset selection is handled via binary signal inputs, a maximum inherent delay of approximately 100 ms must be taken into account.

Settings for which only one address is given in the following sections are equally effective for all four parameter subsets.