Everything About Grundfos SQ and SQE Pumps

Providing water to a country house, cottage, or summer cottage is an urgent and priority task today. One of the solutions is the autonomous water supply using borehole pumps. For this purpose, Grundfos offers borehole pumps of the SQ and SQE series. SQ and SQE pumps have a wide range of capacities and heads, allowing the owner to select the equipment that is ideally suited to individual requirements.

Grundfos SQ pumps

SQ pumps are designed to operate in automated water supply systems in cyclic or intermittent operation. The equipment also allows continuous operation for a long time. Continuous loading is possible due to the cooling of the rotating units with the pumped liquid and the structural features of the engine of the unit. It is equipped with permanent magnets, which guarantee the feeding efficiency and stable retention of the calculated height of the water column.

Main SQ characteristics

Based on the functionality, the scope of application of the SQ series pumps is quite wide:

• water intake of surface water and wells;
• water sampling in the course of implementing the tasks of environmental programs.

In everyday life, Grundfos pumping equipment is used when arranging an autonomous water supply system in a cottage house due to the absence of centralized water networks in the village. Besides, SQ pump equipment can be used for the irrigation of agricultural land.

Features of Grundfos SQ pumps

Grundfos SQ pumps are equipped with the following devices and gadgets:

• mechanism that excludes the rotation of impellers without liquid (it protects the equipment from dry running and includes an automatic restart system);
• device for the soft start of a permanent magnet electric motor;
• multi-stage assembly of the pumping part (wheels without rigid fixation ensure high flow rate);
• electromechanical devices that protect against voltage surges, engine overheating.

The Grundfos SQ pump is used for non-corrosive liquids that do not contain fractions of solids or fibers. The maximum permissible concentration of sand is 50 grams per ton of water. Exceeding the threshold negatively affects the durability of polymer wheels and quickly leads to breakdowns. The maximum temperature for the pumped-over liquid is +35 ° С. It is necessary to mention that SQ pumps are operated both vertically and horizontally.

Grundfos SQE Pumps

The multistage pump Grundfos SQE visually and structurally almost completely repeats the SQ. The extensive line of SQE centrifugal units duplicates the configuration, dimensions, and technical parameters of its predecessors. These pumps are used mainly in wells with a minimum diameter of 76 mm. The Grundfos concept of the SQE variable speed pump demonstrates the manufacturer’s commitment to making pumping equipment installation and performance management as easy as possible.

Control Features

With SQE pumps you receive the following control features:

• operational monitoring of the technical condition of the pump without raising it to the surface;
• regulation of the unit productivity depending on the statistical water level in the well and the dynamics of water replenishment;
• maintaining a constant pressure in the water supply network;
• programming of high-speed modes of engine operation;
• maintaining a given water level in tanks;
• remote control of the pump via a mobile application.

SQE Main Characteristics

The connection of electrical cables and polyethylene pipes to the units is carried out without the use of special tools. Characteristics of the power supply network – 240 V (+ 6% / – 10%), 50/60 Hz. Its capabilities must meet the rated power consumption, depending on the pump model, in the range from 0.7 to 1.85 kW. A Grundfos SQE submersible pump installs with a control unit. All pumps are equipped with a cable in a waterproof sheath of the appropriate length based on the parameters of the equipment.

Benefits of Grundfos SQE

• High efficiency and low power consumption. It is achieved through the presence of an innovative permanent magnet electric motor.
• Soft start. Eliminates premature engine failure, which often occurs as a result of a sharp increase in speed.
• Dry run protection. If there is a lack of water, the device automatically turns off. If liquid appears, the system will automatically start after 5 minutes.
• Constant pressure. The engine speed is adjustable from 65 to 100%, which allows you to select the desired operating mode.
• Ascent protection. The upper thrust bearing eliminates any possibility of displacement of the impeller along the shaft axis.
• Comprehensive pump protection system. It minimizes any negative consequences that often occur during the operation of the device.

Differences Between the Grundfos SQ & SQE

The main difference between SQ and SQE – in the automation of SQE models. They are equipped with a frequency converter. Its task is to maintain a given pressure indicator of the working medium in the water supply network. The functionality of the device is provided by MSE electric motor, which, by increasing or decreasing the number of rotations per unit of time, provides the required pressure parameters. This approach makes SQE pumps suitable attractive for stand-alone systems in which the hot water supply circuit is connected with the operation of flow-through gas water heaters (boilers).

A storage tank with an EDPM synthetic rubber membrane is needed to reduce the number of pump starts per day, and a regulator to limit the upper-pressure threshold in the system.

Common Features of SQ & SQE Pumps

Soft start

The soft start of the Grundfos SQ and SQE increases durability and eliminates the risk of overload when starting the pump. Thus, pipes are less susceptible to water hammer during starts and stops. As a result of the lack of starting current, the electric motor does not undergo significant heating, which in turn does not impose a limitation on the number of starts per hour and allows the use of a membrane tank with a smaller volume, and also makes it possible to use a generator and stabilizer. All this allows you to achieve maximum reliability with lower equipment costs.

Overvoltage protection

For suburban electric networks, power outages and the presence of voltage surges that threaten the normal operation of the pump are characteristic. The SQ/SQE pump motor has a unique operating voltage range of 150V to 315V while maintaining near-nominal performance. If the specified range limits are exceeded, the motor electronics switches off the pump, and then, as soon as the permissible operating voltage is established, the pump automatically turns on and continues to work in nominal mode.

Built-in overheat protection

The pump electric motor will be reliably protected from overheating for many years of operation. Grundfos SQ/SQE pumps have an integrated temperature sensor. If the maximum allowable temperature is reached, the pump will turn off itself. Restarting occurs automatically after the temperature drops below the set value.

Absolute tightness

The design of the Grundfos SQ/SQE pump is properly developed to ensure complete tightness of the control electronics built into the electric motor.

High wear resistance

Grundfos uses high-strength composite materials and high-quality stainless steel to manufacture the SQ/SQE series pumps. The design uses durable tungsten carbide bearings.

Overload protection

A blocked impeller or shaft puts an increased load on the pump, causing increased current consumption. The protection built into the motor compensates increased current consumption by reducing the shaft speed. When the speed drops below 65% of the rated speed, the pump is automatically turned off. This ensures reliable pump overload protection.

Dry run protection

The motor of the Grundfos SQ/SQE pump automatically turns off when there is a lack of water in the well. This prevents damage to the pump itself. After 5 minutes the pump will try to restart automatically.

Simple Installation

Grundfos pumps SQ/SQE series are compact. The diameter is 74mm and the pump can be used in wells with a diameter of 3 inches, which in turn saves on drilling costs. Besides, the low weight of the pump facilitates the process of installing and equipping the well, while no special devices (crane beams, blocks, etc.) are required to lower the pump into the well. A qualified technician does not require a lot of time to perform the installation of the pump.