1
Why must the pump unit be installed below the dynamic water table?
2
Why is correct sizing of the submersible pump important?
3
The 3” SQ pump is obviously ideal for new boreholes but where can it also be used?
4
Why is it important to protect the pump from over- and under voltage?
5
How long did it take to replace the pump with a Grundfos SQ?
6
Where is domestic groundwater extraction typically relevant?
7
How many times higher than nominal speed does the motor current reach during the first milliseconds?
8
How does the integrated dry-running protection work?
9
Which of these isn’t a key dry-run protection benefit for the installer?
10
What is the most commonly used starting method for motors in 4” conventional pumps?
Test results
Q: Why must the pump unit be installed below the dynamic water table?
A: So you are sure to minimise your power bill.
Q: Why must the pump unit be installed below the dynamic water table?
A: To avoid the risk of dry-running during operation.
Q: Why must the pump unit be installed below the dynamic water table?
A: To maintain a stable pressure in the system.
Q: Why is correct sizing of the submersible pump important?
A: Because an undersized pump will not be able to deliver the required flow and pressure and an oversized pump reduces energy efficiency, which increases operational costs.
Q: Why is correct sizing of the submersible pump important?
A: Because too small a pump will pump the well dry.
Q: Why is correct sizing of the submersible pump important?
A: Because too big a pump will ruin the taps due to too high pressure.
Q: The 3” SQ pump is obviously ideal for new boreholes but where can it also be used?
A: In wells with water temperature up to 60° C.
Q: The 3” SQ pump is obviously ideal for new boreholes but where can it also be used?
A: In installations that require constant pressure.
Q: The 3” SQ pump is obviously ideal for new boreholes but where can it also be used?
A: In original 4” boreholes where sediments over the years have narrowed the hole.
Q: Why is it important to protect the pump from over- and under voltage?
A: Because large variations in power supply will damage the motor over time.
Q: Why is it important to protect the pump from over- and under voltage?
A: To avoid burning the house fuses.
Q: Why is it important to protect the pump from over- and under voltage?
A: To minimise the power consumption.
Q: How long did it take to replace the pump with a Grundfos SQ?
A: 30 minutes
Q: How long did it take to replace the pump with a Grundfos SQ?
A: 60 minutes
Q: How long did it take to replace the pump with a Grundfos SQ?
A: 90 minutes
Q: Where is domestic groundwater extraction typically relevant?
A: In big cities.
Q: Where is domestic groundwater extraction typically relevant?
A: In remote areas where it is too costly to extend the municipal water supply to just a few houses.
Q: Where is domestic groundwater extraction typically relevant?
A: In smaller and medium sized towns.
Q: How many times higher than nominal speed does the motor current reach during the first milliseconds?
A: Four times higher
Q: How many times higher than nominal speed does the motor current reach during the first milliseconds?
A: Six times higher
Q: How many times higher than nominal speed does the motor current reach during the first milliseconds?
A: Seven times higher
Q: How does the integrated dry-running protection work?
A: It automatically restarts 3 minutes after shut down.
Q: How does the integrated dry-running protection work?
A: It prevents sand from damaging the pump.
Q: How does the integrated dry-running protection work?
A: It automatically shuts down the pump if water shortage is detected.
Q: Which of these isn’t a key dry-run protection benefit for the installer?
A: He can avoid costly callbacks
Q: Which of these isn’t a key dry-run protection benefit for the installer?
A: He doesn’t have to worry about additional components
Q: Which of these isn’t a key dry-run protection benefit for the installer?
A: He doesn’t have to worry about water bursts
Q: What is the most commonly used starting method for motors in 4” conventional pumps?
A: Direct on line
Q: What is the most commonly used starting method for motors in 4” conventional pumps?
A: Star delta starters
Q: What is the most commonly used starting method for motors in 4” conventional pumps?
A: Auto transformer