Once a submersible pump has been installed under ground, nothing is more important than reliable operation as service is both troublesome and costly.    

In this tutorial we will take a closer look at the most important features and benefits of the SQ/SQE pump to show you just how robust and well-prepared for under ground operation the pump is.

Let’s begin by looking at the SQ/SQE pump’s built-in protection functionalities. These include protection from: Over- and under voltage Dry-running Overload Let’s go through them one by one to find out in more detail how they help ensure reliable performance – both during water shortage or fluctuating power supply.

Large variations in power supply like under-voltage and over-voltage will damage a conventional AC motor over time. The robust SQ/SQE has a very wide supply voltage range, which in itself reduces the risk of overheating the motor.

Should the voltage move outside the interval between 150 V and 315 V the pump will automatically stop to protect the motor. When the voltage is once again within the acceptable limits, the pump will restart.

The illustration compares the voltage range of a conventional pump with the SQ/SQE pump’s range. A narrow range is likely to cause frequent, inconvenient stops or damage the pump.  

Dry-running may cause a pump to break down – especially if it is operated in an area with low yielding wells. The integrated dry-running protection in the SQ/SQE pump automatically shuts down the pump if water shortage is detected.

After 5 minutes the pump will attempt a restart. If there is still no water, it will stop again and attempt a new restart 5 minutes on. This cycle will continue until water is again detected in the pump.

Now, let’s turn to the problem with overload. Pumps are typically exposed to excessive load when the power consumption increases – for instance during start-up when the pump is running at high speed.

Thanks to the built-in soft start functionality, the SQ/SQE pump limits the current draw from the mains to prevent damaging overload of the electrical installation. The diagram illustrates the difference in current draw between a conventional pump and an SQ/SQE pump during start-up.  

But the advantages of the soft-start functionality do not stop here. A soft start of the pump also: Reduces the occurrence of water hammer in the pipes And minimises pump wear during start-up. Both of these benefits prolong the life of the SQ/SQE pump.

So, the line of built-in protection functionalities is long and means that you need no additional protection equipment to ensure reliable operation under ground when you chose the SQ/SQE pump for your groundwater application.

The pump is easy to install thanks to its light weight and does not require an external starter box.