PUMP SUMP CONFIGURATION

Pump sumps are designed to receive liquids and be intermittently drained. The sump size depends on the capacity Q and permissible start-up frequency Z of the pump set The electric motor.
The start up frequencies of any dry motors are as follows :

Motor rating Start up frequency
Up to 7.5 kW max. 15/h
Up to 30 kW max. 12/h
Above 30 kW max. 10/h
Start up frequency is calculated using :

The maximum start up frequency occurs when Qm = 2 x Qzu, when the capacity Qm is twice the incoming flow Qzu. The max. start up frequency is there fore :

With the dry liquids, solids must be prevented from being deposited and collecting in dead zones and on the floor. 450 walls, or better still 600 walls, help prevent this (see fig.1)