Fire pump (dual use and one standby) soft starter control circuit b

The soft starter control circuit of the fire pump (dual use and one backup) using FSR1000X soft starter is shown in Figure 5-27. When
the transfer switch 1SA is placed in the automatic position, the two-purpose and one standby operation is carried out, and the standby is automatically switched; when the transfer switch 1SA is placed in the manual position, the
individual units are operated manually. When the transfer switch 2SA is set to 1, pump 8 is in standby, pump 1# is in standby, when pump 2# is in standby, pump 2# is in standby
, and when pump 3# is in standby, pump 38 is in standby. After the faulty standby is automatically switched on, the transfer switch 2SA needs to be switched, and then
the power supply of the faulty pump is cut off before maintenance can be carried out.
    In the figure, KY is the control contact of the fire control room; SSI~ss. It is an external fire button.
The delay setting value of the time relay (2KT) is greater than the soft start time of a single unit.