centrifugal pump startup

Why? Are you planning to destroy your pump ?

This is the normal way to start a standard single stage centrifugal pump. Suction fully open, discharge closed or cracked open. Roughly no load amperage for the motor as stated by others.

If you have the pump operating curve that includes the curve for power consumption you can see the kW or horsepower consumed. It would be at the far left at the zero flow point.

BE CAREFUL !! YOU CAN START A CENTRIGUGAL PUMP WITH DISCHARGE VALVE CLOSED ONLY, AND ONLY IF IT IS A SINGLE STAGE CENTRIFUGAL PUMP. > > MAKE SURE. IN THAT CASE THE PUMP WILL DRAW ONLY THE NO LOAD AMPS AS THERE WILL BE NO FLOW AND HENCE NO LOAD.

AGAIN, IF YOU TRY THIS WITH A MULTI-STAGE CENTRIFUGAL PUMP BE CERTAIN THAT THERE COULD BE SERIOUS DAMAGE TO THE PUMP, VALVES,AND PERSONNEL.

VINOD CHANDRA

The blocked flow pump should consume minimal current, but it heats up as energy of flow changes into heat, thus its better to close sucktion valve during starting up

Rubbish - never ever start a centrifugal pump with a closed suction valve.

This will be the locked rotor current.

Sorry. No cigar. It will be no flow current as in post #2. This is referred to as deadheading the pump. The impeller still spins, but no fluid movement is occurring. This causes very rapid internal heating and soon destruction as Vader hinted.

This is not a good practice.

Lynch

Wrong. No load current.