Grundfos Pump 45S75-15

Verify minimum number of starts per year

Check maximum number of starts per hour and per day (for reference only)

Has the pump been run at least once this year to prevent issues from prolonged inactivity?

Motor Protection — Required Settings of Motor-Protective Circuit Breaker

Ensure the motor-protective circuit breaker is set to the rated maximum current of the motor.

Start the pump and let it run for half an hour at normal performance.

Slowly grade down the scale indicator until the motor trip point is reached.

Is the setting within the permissible range (not exceeding the rated maximum current of the motor)?

For motors wound for star-delta starting, ensure the motor-protective circuit breaker is set to rated maximum current × 0.58.

Is the startup time for star-delta starting or autotransformer starting within 2 seconds?

Ensure power supply cannot be accidentally switched on

Measure the voltage between the phases using a voltmeter

Is the voltage within the specified range when the motor is loaded?

Stop the pump if there are large variations in voltage

Measure the amps of each phase while the pump is operating

Ensure the pump is connected to protective earth

Switch off the power supply before starting any work on the product

Ensure the power supply cannot be accidentally switched on

Is the pump submerged in the liquid to be pumped?

Set the outlet valve to approximately 1/3 of its maximum volume of water

Check the direction of rotation as described in the section on Connection of three-phase motors

Are there impurities in the water?

Open the valve gradually as the water becomes clearer

Check the level of motor liquid

Is the motor liquid level sufficient?

Refill motor liquid using tap water if necessary

Is the motor delivered from stock?

Is the motor liquid level checked during service?

Position the submersible motor so the filling screw is at the highest point of the motor

Remove the screw from the filling hole