One use and one standby constant pressure water supply frequency conversion speed control circuit b

The soft start control circuit of the fire pump (one in use and one in standby) using FSR1000X soft starter is shown in Figure 5-26. When the transfer
switch 1SA is placed in the automatic position, one of the two fire pumps is running and the other is in standby. The two pumps are standby for each other
. After an operation failure, the standby pump is automatically put into operation immediately. When 1SA is placed in the manual position, both pumps can be operated manually and independently. The time relay
(KT) delay setting value is greater than the soft start time of a single unit.
    In the figure, 1 and 2 are bypass relay terminals ; 3 and 4 are fault output terminals; 7 is instantaneous stop input terminal; 8 is soft stop
input terminal; 9 is soft start input terminal; 10 is common contact input terminal (COM ); Il is the ground terminal (PE);
12 and 13 are the control power input terminals .