Maximise water and energy savings
Grundfos delivers a complete range of solutions for the pressure and flow requirements of drip and micro-spray applications. Drip irrigation is extremely efficient and flexible, because water and nutrients are applied directly to the root zone with minimal runoff and evaporation. Designed with a soaker hose either buried or lying flat near the plants, drip irrigation systems ensure uniform delivery while helping to reduce waste and runoff.
We can also integrate chemical injection equipment, like our advanced digital dosing pumps, into your system to ensure crops receive a uniform application of nutrients. Our full range of offerings is designed for maximum energy efficiency.
Get answers to your questions about this application
We have gathered frequently asked questions and their answers in one place. See the most frequently asked questions below or go to the Grundfos FAQ for a complete list of answers to your questions about our products.
What types of media can I pump with a submersible pump?
Pure, low-viscosity, non-explosive media without solid matter or long fibrers.
If a liquid with a density differing from that of water is to be pumped, the motor power required due to the change in hydraulic power should be taken into account.
When pumping fluids more aggressive than drinking water, the special material construction pump versions such SP N, SP R and SPNE should be used.Read more
Is it possible for submersible motor pumps to run dry?
Dry running of Wastewater Pumps can damage the mechanical seal and the motor. For this reason, the float switches should be arranged so that the fill level in the shaft does not fall below the minimum level required to operate the pump. (See also ‘What minimum fill level is required to properly operate the pump?’). The actual conditions prevailing in the application in question must therefore always be reconciled with the information provided in the operating instructions or the datasheet before initial start-up of the pump.
On submersible well pumps, it is possible for a submersible pump to run dry. This caused by over pumping the well where the depth to water level drops while the pump is running. Until the water level in the well reaches down to the pump intake screen. Often submersible pumps pump more water then recovers into the well. Lowering the pump further down the well is the most common solution. Adjusting tank size and demand cycles also helps.
How do I set the motor protection on a submersible pump?
Setting the motor protection on a submersible pump
The overcurrent release integrated into the motor-protection switch must trip on cold start in less than 10 seconds at five times the maximum motor current stamped on the rating plate.
In order to provide the best possible protection to the submersible motor, the motor-protective switch should be set in accordance with the following guidelines:
1. Set overcurrent release to the stamped maximum motor current.
2. Let the pump run for half an hour at normal power.
3. Set the overcurrent release successively lower until the trip point is reached.
4. After that, set the overcurrent release 5% above this trip point.
If the tripping characteristic of the motor-protection switch does not fulfil these requirements, the motor warranty is void. The maximum adjustment value of the overcurrent release must not exceed the maximum motor current stamped on the rating plate. For motors wound for star-delta start-up, proceed as follows when setting the motor-protection switch, but note that the protective switch setting must not exceed a maximum value of:
Protective switch setting = stamped max. current x 0.58.
The maximum permissible start-up time for star-delta starters or for motor switches with autotransformers is 2 seconds.
Grundfos offers different devices for motor protection like the MP204 module, for further information, refer to CAPS.Read more
Can the pump be operated using a frequency converter?
Grundfos offers numerous speed-controlled pumps that are referred to as ‘E-pumps’ and which come equipped with Grundfos MGE motors with an integrated frequency converter. The manufacturing costs and material inputs are lower compared to pump solutions with external frequency converters. In addition, technical issues that may arise in connection with external frequency converters are avoided.
Finally, MGE motors have numerous additional features and advantages. In the event that no E-pump is available for a specific application, it is generally possible to operate the three-phase industrial motors offered by Grundfos via an external frequency converter. The technical information set out in the operating instructions and datasheet should be referred to in each individual case.
All Grundfos submersible well motors can be operated using a frequency converter. However, the setup can vary from one type of submersible pump to another.
SQE, all sizes uses a built-in frequency converter working with CU301 Controller.
SP, all sizes, uses an external frequency converter, sold separately.
SPE, all sizes, requires an external frequency converter to start the motor, sold separately.