General description
SPE is a speed-controlled submersible pump system with a permanent magnet motor. It has a low running cost and can be used in changing operation conditions. The pump is suitable for a number of applications within groundwater pumping, for example the following:
• water supply
• irrigation
• groundwater lowering.
An all-stainless steel construction in three different material grades ensures that the pump can be used for
both clean water as well as corrosive water.
The pump system consists of reliable hydraulics and an energy efficient IPM (Interior Permanent Magnet) type
motor. The magnets are embedded in the rotor. The magnets in MS6000P are further protected as the rotor is
hermetically sealed with a thin layer of metal. The motor design furthermore consists of the following:
• canned stator design
• mechanical shaft seals with Silicon Carbide seal faces
• heavy duty thrust bearings.
The motor is running synchronous and needs a Variable Frequency Drive (VFD), such as the Grundfos CUE, to
control the speed according to need. The CUE includes a wizard to make the setup easy. The CUE has the following predefined control modes:
• constant pressure
• constant flow
• constant level.
The CUE also features protection of the pump installation, including minimizing risk of water hammer and reducing stresses to the submersible motor during start by means of a soft starter function.
ErP ready
The SPE pumps are energy-optimised and comply with the ErP Directive (Commission Regulation (EC) No
547/2012) which is in effect from 1 January 2013. From this date, all pumps are classified and graduated in a new energy efficiency index (MEI).
Minimum efficiency index
Minimum efficiency index (MEI) means the dimensionless scale unit for hydraulic pump efficiency at best efficiency point (BEP), part load (PL, 75 % BEP) and overload (OL, 110 % BEP). The Commission Regulation (EU) sets efficiency requirements to MEI ≥ 0.40 as from 1 January 2015. An indicative benchmark for best-performing water pump available on the market as from 1 January 2013 is determined in the Regulation.
• The benchmark for most efficient water pumps is MEI ≥ 0.70.
• The operation of the pump is efficient and economic as it is controlled by a variable frequency drive which
enables the pump set to match varying performance requirements from the system.
• Information on benchmark efficiency is available at http://europump.eu/efficiencycharts.
Applications
SPE pumps are developed for pumping ground water from boreholes. The pumps are installed in boreholes or wells, submerged below the water level.
For industrial purposes, the pump can be placed for example, in a tank.
The pumps are suitable for the following applications:
• raw-water supply
• irrigation
• groundwater lowering
• pressure boosting
• fountain applications
• mining applications
• offshore applications.
Submersible pumps
Features and benefits
A wide pump range
Grundfos offers energy-efficient submersible SPE pumps ranging from 10 to 280 m3/h. The pump range consists of pump sizes from SPE 17 to SPE 215. Each pump size is available with an optional number of stages to match a given duty point.
High pump efficiency
Often pump efficiency is a neglected factor compared to the price. However, it is important to notice that price
variations are without importance to water supply economics compared to the importance of pump and motor efficiencies.
Example
If pumping 70 m3/h at 100 m head for 10 years a normal pump set consumes approximately 2,775,000 kWh. By changing to an SPE high efficiency pump set the increased efficiency will result in a reduction of 274,200 kWh, corresponding to more than € 27,400 cost saving at a price of 0.10 €/kWh. In variable demand conditions the saving is even higher.
Material and pumped liquids
To ensure the right wear resistance and reduce the risk of corrosion, the pump ranges are available with the following steel variants:
• SPE: EN 1.4301
• SPE N: EN 1.4401
• SPE R: EN 1.4539
See specified material variants in Pump range. For further protection in corrosive environments, a complete range of zinc anodes for cathodic protection is available. See Zinc anodes.
Rubber components
For pumping liquid with risk of chemical residue or liquids above 60 °C, all pumps can be supplied with rubber components made of FKM elastomer.
Low installation costs
Stainless steel sheet metal means low weight. This facilitates the handling of pumps and results in low equipment costs, reduced installation and service time.
Submersible permanent magnet motors
For further information about Grundfos MS6000P submersible motors, see the MS motor literature available
in Grundfos Product Center at https://productselection.grundfos.com.
Features and benefits
Grundfos offers a complete range of 6 inch submersible motors of IPM (Interior Permanent Magnet) design, named MS6000P. These are based on the Grundfos MS6000 motor platform including the mechanical construction, thrust bearings with high thrust capability and shaft seals. The permanent magnet motor is a 4-pole synchronous motor, requiring a variable frequency drive as it cannot be directly connected to the electricity grid, contrary to the asynchronous motor.
The MS6000P permanent magnet motor offers the following advantages:
• 8-10 % higher efficiency compared to an asynchronous motor with the same output power.
• More compact design due to the high energy density of the permanent magnets, thus offering a lighter motor with a higher output.
• Reduced internal temperature in the motor, due to the high efficiency
• Strong permanent magnets. The Grundfos 6 inch version is based on 20 years of operating experience with a similar design.
The MS6000P is available in T60 version only. This means that the motor is able to operate in applications up to 60 °C as long as a standard cooling flow of 0.15 m/s is ensured. In most applications the media temperature is less than 60 °C and the surplus temperature capacity ensures an even more robust motor.
For particularly demanding applications in corrosive media MS6000P is available in stainless steel quality 1.4539, called R version. Typical applications are the following:
• Mining dewatering
• Fish farming
• Offshore industrial applications
Stator
Grundfos MS6000P consists of a hermetically sealed stator withstanding external pressure up to 30 bar. It is a 4-pole construction with insulation class F winding material. All surfaces in contact with the pump media are mad of stainless steel. The following material grades are available:
• EN1.4301 for non-demanding installations (approved for drinking water).
• EN1.4539 for installations with high chloride content.
The stator is filled with an epoxy filler and wound for high robustness using grade two, over coated enamel winding wire.
Shaft and rotor
The NEMA splined shaft extension is friction welded to a stainless steel shaft. Stainless steel radial bearing bushes on the shaft form the rotating part of the radial bearings.
Stationary part of the radial bearing is a carbon or graphite bush. The rotor pack consists of indexed segments with integrated (buried) rare earth magnets placed as a 4-pole construction. This makes the motor an IPM type. The rotor pack is hermetically sealed by a metal cladding welded onto the shaft. This ensures a long life time and prevents corrosion of the magnets. The bottom of the shaft has the rotating part of the thrust bearing mounted and the entire shaft is gun drilled in order to ensure lubrication of the mechanical shaft seal and the radial bearings. Due to the use of permanent magnets no heat is generated in the rotor pack and subsequently the temperature rise in the motor liquid will decrease drastically. This benefits the life time of the construction and ensures more robust lubrication film in the radial and thrust bearing.
Thrust bearing
Grundfos MS6000P uses identical thrust bearing to the MS6000 series consisting of a ceramic rotating disc running against tilting pads and carbon or graphite shoes on the stationary part.
Shaft seal system
Grundfos MS6000P has a rubber sand slinger covering the top of a stainless steel shaft sealing house. When the shaft starts rotating, settled sand is removed from the shaft seal area due to the centrifugal force.
Inside the shaft seal house, a lip seal is placed above a mechanical shaft seal with SIC/SIC faces placed in NBR rubber elastomers. The shaft seal construction enables drinking water approval of the finished product.
The shaft seal is according to EN 12756.
Lightning protection
Use extra lightning protection or surge arrestor for the electrical panels in relation to the SPE system.
Grundfos variable frequency drive for SPE
To operate the SPE pump, a variable frequency drive is required. Grundfos offers the CUE for this purpose.
For use in solar application, Grundfos an RSI is recommended. For further information about Grundfos RSI and Solar, see the literature available in Grundfos Product Center at https://product-selection.grundfos.com.
CUE variable frequency drive
Grundfos CUE is a series of external variable frequency drives designed for speed control of a wide range of Grundfos pumps, including SPE.
When a CUE is installed, the motor does not require further overload protection. Pt100 or Pt1000 together with MCB 114 sensor input module can provide overheating protection of the motor
windings, if needed.
CUE offers quick and easy setup and commissioning compared to a standard variable frequency drive as the startup guide is designed specifically for Grundfos pumps, including SPE.
Functions
CUE has a wide range of pump-specific functions. For groundwater applications, the following are especially relevant:
• constant pressure
• constant level
• constant flow rate.
CUE features
• startup guide
• easy setup
• check of the direction of rotation
• duty and standby operation
• dry-running protection
• low-flow stop function.
The CUE startup guide is automatically activated at the first startup. Here, a number of parameters are set automatically based on the pump type. Other parameters are set manually based oin the data indicated on the motor and pump nameplates. The startup guide can be repeated, if necessary. Due to the startup guide, the installer can quickly set central parameters and put CUE into operation.
Sensors
The following sensors can be used in connection with CUE:
• pressure sensors, up to 25 bar
• temperature sensors
• differential-pressure sensors
• differential-temperature sensors
• flowmeters
• potentiometer box for external setpoint setting.
All sensors are with 4-20 mA output signal.
SPE and sine-wave filter
Grundfos SPE pump systems, consisting of one SP, one MS6000P and one CUE, meet the VFD and motor input requirements in the table below. When application and grid requirements are fulfilled, a sine-wave filter is not required.
Sine-wave filter
If the above VFD requirements are not met, the use of output sine-wave filters is required for SPE pumps.
The purpose of the output filters is the following:
• protect the motor from overvoltage and increased operating temperature.
• reduce voltage stress on the motor windings and stress on the motor insulation system
• decrease acoustic noise from the motor that is driven by a variable frequency drive.
Sine-wave filters have a particularly high degree of filtering, resulting in high reduction of motor insulation stress and elimination of switching acoustic noise from the motor. The motor losses are reduced as the motor is fed with a sine-wave voltage and the filter eliminates the pulse reflections in the motor cable.
Sine wave filter selection
Filters used with SPE must be selected according to motor current and filter rating at 100 Hz (3000 RPM).
The range of Grundfos SPE 60 is as below
SPE 95-1
SPE 95-2
SPE 95-3
SPE 95-4
SPE 95-5
SPE 95-6
SPE 95-7
SPE 95-8
SPE 95-9
