Grundfos SQ, SQE Manual

Product introduction

Electric shock
Death or serious personal injury

• The pump must not be used when people are in the water.

Fill the page with nameplate data before installing the product.

Applications

The SQ and SQE pumps are designed for pumping thin, clean, non-aggressive, non-explosive liquids, not containing solid particles or fibres.
Typical applications:

• Groundwater supply for
  • private housing
  • households
  • small waterworks - irrigation systems.
• Liquid transfer in tanks.
• Pressure boosting.

Generator operation

It is safe to operate the SQ/SQE with a generator.
The pump can safely be operated with a generator that is sized 50% above the P₁ (input power) values of the pump.

Installation requirements

Installation depths

Maximum installation depth below the static water level is 150 metres.
See the section on pipework connections.
Minimum installation depth below the dynamic water level:

• Vertical installation: During start-up and operation, the pump must always be completely submerged in water.
• Horizontal installation: The pump must be installed and run at least 0.5 metres below the dynamic water level.
• Fit a flow sleeve if there is a risk that the pump will be covered by mud.
  Installation depth
  

Dynamic water level must be above the pump.

Positional requirements

Make sure that the pump does not fall below the horizontal plane.

Positional requirements of the pump

Well preparation

If the pump is to be installed in a well, clear any sand and oil from it, as no pump can withstand constantly pumping sandy water.

Pumped liquid requirements

The maximum sand content of the water must not exceed 50 g/m³. A larger sand content will result in pump lifetime reduction and in blockage.
Before pumping liquids with higher viscosity than water, contact Grundfos.
pH values: 5-9.
Liquid temperature:
The temperature of the pumped liquid must not exceed 35°C.
If the actual temperature of the pumped liquid exceeds the specified value or the operating conditions otherwise fall outside the specified conditions, the pump may stop. Contact Grundfos.

Liquid temperatures and cooling

SQ/SQE pump in a borehole
Install the motor above the well screen. If a flow sleeve is used, the pump can be installed freely in the borehole.

Make sure the temperature of the pumped liquid does not exceed 35°C for sufficient motor cooling.

The borehole diameter must be at least 76 mm.
Install the motor above the well screen. If a flow sleeve is used, the pump can be installed freely in the borehole.
Do not run the pump against a closed valve for more than 5 minutes as there is no cooling flow which results in motor and pump overheat.

Selection of diaphragm tank, precharge pressure setting and pressure switch

Pressurised system

Death or serious personal injury

• The installation must be designed for the maximum pump pressure.
  The pump has a built-in soft starter providing 2 seconds run-up time. Therefore the pressure at the pressure switch and diaphragm tank during start is lower than the pump cut-in pressure set on the pressure switch. This lower pressure is called minimum pressure (P_min = B + C).
  Diaphragm tank and pressure switch
  

Make sure that the selected pump can deliver a pressure higher than P_cut-out + A.

Well system pressure overload

To prevent overpressure, install a pressure relief valve downstream of the well head. The setpoint of the pressure relief valve must be at least 30 psi above the pressure setting.
If a relief valve is installed, make sure it is connected to an appropiate drainage point.
Using P_min and Q_max, the minimum diaphragm tank size, precharge pressure and pressure switch settings can be found in the guideline table below:
Example
P_min = 35 m head, Q_max = 2.5 m³/h.
On the basis of this information, the following values can be found in the table:
Minimum diaphragm tank size = 33 litres.

1 m head = 0.098 bar.

Installing the product

Electric shock
Death or serious personal injury

• Before starting work on the pump, make sure that the power supply has been switched off and that it cannot be accidentally switched on.
• The pump must be earthed.
• The pump must be connected to an external mains switch with a minimum contact gap of 3 mm in all poles.
• If the motor cable is damaged, it must be replaced by Grundfos, an authorised Grundfos service workshop or similarly qualified persons to avoid a hazard.

The supply voltage, rated maximum current and power factor (PF) appear from the motor nameplate.
The required voltage for Grundfos submersible motors, measured at the motor terminals, is -10% to +6% of the nominal voltage during continuous operation including variation in the supply voltage and losses in cables.

Electric shock
Death or serious personal injury

• If the pump is connected to an electric installation where an earth-leakage circuit breaker (ELCB) is used as an additional protection, this circuit breaker must trip out when earth fault currents with DC content (pulsating DC) occur.

The earth leakage circuit breaker must be marked with the following symbol: .

Electric shock
Death or serious personal injury

• Do not lower or lift the pump by means of the motor cable.

Toxic material

Death or serious personal injury

• Thoroughly clean the pump before pumping drinking water.
• Do not use the pump for drinking water if the internal parts have been in contact with particles or substances not suitable for water intended for human consumption.

The electrical connection must be carried out by an authorised electrician in accordance with local regulations.

The pump must be installed according to national water regulations and standards.

The pump must never be connected to a capacitor or to another type of control box than CU 302.
The pump must never be connected to an external frequency converter.
Fix the separate nameplate supplied with the pump close to the installation site.

Supply voltage
1 × 200-240 V -10% / +6%, 50/60 Hz, PE.
The current consumption can only be measured by with a true RMS instrument. If other instruments are used, the value measured will differ from the actual value.
On SQ/SQE pumps, a leakage current of 3.5 mA at 230 V, 50 Hz, can typically be measured. The leakage current is proportional to the supply voltage.
The SQE pump can be connected to a control box, type CU 302.

Preparation

Grundfos MS 3 and MSE 3 submersible motors have water-lubricated slide bearings. No additional lubrication is required.
The submersible motors are factory-filled with a special Grundfos motor liquid (type SML 3), which is frost-proof down to -20°C and preserved to prevent the growth of bacteria.

Motor liquid refill
The level of motor liquid is decisive for the operating life of the bearings and consequently the life of the motor.
If for any reason the motor liquid has been drained or lost, the motor must be refilled with motor liquid.

Use Grundfos motor liquid SML 3.
To refill the motor, proceed as follows:

1. Remove the cable guard and separate the pumppart from the motor.
   Refilling of motor liquid
   
2. Place the motor in vertical position with aninclination of approx. 10°. If placed in a vice, see the section on Assembly of pump part and motor.
3. Remove the filling plug using a screwdriver or asimilar tool.
4. Inject motor liquid into the motor with a fillingsyringe or with a similar tool.
5. To allow possible air to escape, move the motorfrom side to side.
6. Refit the filling plug and make sure it is tight.
7. Assemble the pump part and the motor. See thesection on Assembly of pump part and motor.
8. Refit the cable guard.

Cable sizing
Before installing the pump, make sure to use the right cable size for the submersible drop cable.
The cross-section of the submersible drop cable must be large enough to meet the voltage requirements.

Maximum cable length calculation
Use the following equation ¹⁾:

1) Power factor (PF) of the motor unit is 1.

Explanation of the equation

Maximum motor current
The maximum motor current depends on the motor properties and electrical installation. According to IEC 60364-5-52:2009, the installation and cable must be dimensioned for a current that is higher than the maximum motor current.

Maximum recommended voltage drop

• According to IEC 60364-5-52:2009 for installation in domestic applications, the maximum recommended voltage drop is 5% for cable lengths up to 100 m.
• For installation in industrial applications and in regions where the IEC standard is not applicable, local regulations may require that a different maximum value for voltage drop must be used for the calculation of the maximum cable length.

Specific resistance of the drop cables
The specific resistance of the drop cables supplied by Grundfos for SQ and SQE pumps is 0.02 Ω mm²/m.

Maximum cable lengths for Grundfos MSF 3 motors
Calculation of maximum cable length for the different motor sizes is based on a voltage drop of 5% and a supply voltage of 240 V.
If the calculation above cannot be used, go to Grundfos Product Center for sizing.

Motor protection

The motor incorporates thermal overload protection and requires no additional motor protection.

Connection of motor

The motor can be connected directly to the mains.
Start/stop of the pump typically done via a pressure switch.

The pressure switch must be rated for the maximum amps of the specific pump size.

Connection of motor

Fitting the cable guard

To fit the cable guard, proceed as follows:

1. Make sure that the submersible drop cable lies flatin the cable guard.
2. Place the cable guard in the groove in the cableplug. The two flaps of the cable guard must engage with the upper edge of the pump sleeve.
   Placement of the cable guard in the cable plug
   
3. Fasten the cable guard to the pump suctionstrainer with the two self-tapping screws supplied.
   Fastening of the cable guard to the pump suction strainer
   

Fitting the submersible drop cable

Connect the submersible drop cable and the motor cable with a type KM Grundfos cable termination kit. Connect the submersible drop cable and the motor cable with a type KM Grundfos cable termination kit.

For larger cross-sections, contact Grundfos.

Pipework connection

Pressurised system

Death or serious personal injury

• Make sure that the pipework has an adequate pressure rating.

Before determining the installation depth of the pump, take the expansion of plastic pipes into consideration.
When the riser pipe is fitted, use a chain pipe wrench. The pump must be gripped by the pump discharge chamber.

Gripping the pump
When connecting plastic pipes, use a compression coupling between the pump and the first pipe section.
Where flanged pipes are used, in case of flanged pipes, use slotted flanges so they can take the submersible drop cable.
The figure Pipework connection below shows a pump installation.

Pipework connection

Cable clips
Cable clips must be fitted every 3 metres.
When connecting plastic pipes, fit the cable clips loosely as plastic pipes expand when loaded.
Where flanged pipes are used, fit the cable clips above and below each joint.

When lowering the pump into the borehole
Secure the pump with an unloaded straining wire.
Loosen the straining wire so that it becomes unloaded and lock it to the borehole seal with wire locks.

The straining wire must not be used for pulling the pump with riser pipe out of the borehole.

Start-up

Do not start the pump until it is completely submerged in the liquid.
Start the pump and do not stop it until the pumped liquid is completely clean, otherwise the pump parts and the non-return valve may clog.

Minimum flow rate

Make sure that the flow rate is least 50 l/h to have proper motor cooling.

The pump dry-running protection is effective only within the recommended duty range of the pump.

Built-in protection

In case of overload, the built-in overload protection stops the pump for 5 minutes, then it restarts.
If the pump stopped because of dry running, it starts automatically after 5 minutes.
If the pump is restarted and the borehole is empty, the pump stops after 30 seconds.
To reset the pump, switch of the power supply for 1 minute.
The motor is protected in case of:

• dry running
• voltage surges (up to 6000 V) In areas with high lightning intensity, external lightning protection is required.
• overvoltage
• undervoltage
• overload
• overtemperature.

SQE pumps, MSE 3 motors
Via the CU 302, the dry-running stop limit of the MSE 3 motors can be adjusted to match the actual application.

Maintenance and service

Service kits, service tools and the Grundfos Service Manual are available on request from Grundfos.
The pumps can be serviced at a Grundfos service centre.

Contaminated pumps

Toxic or radio active liquid

Death or serious personal injury

• If a pump has been used for a liquid which is injurious to health or toxic, the pump will be classified as contaminated.

Before servicing the pump make sure to notify the personnel about the pumped liquid.
If Grundfos is requested to service the pump, Grundfos must be contacted with details about the pumped liquid, etc. before the pump is returned for service. Otherwise, Grundfos can refuse to accept the pump for service.

Assembly of pump part and motor

1. Place the motor horizontally in a vice and tightenit. Make sure that the vice clamps on the hatched area of the motor. See the figure Assembly of pump part and motor below.
2. Pull the pump shaft out to the position shown infigure Position of pump shaft.
   Position of pump shaft
   
3. Grease the motor shaft end with the greasesupplied with the motor.
4. Screw the pump part on the motor (55 Nm).

The pump shaft must engage with the motor shaft. Use a spanner on the clamping faces of the pump part.

Assembly of pump part and motor, showing available area for clamping

Make sure there is no clearance between the pump part and the motor.

Removal of non-return valve

1. Cut off the legs of the valve guide using sidecutting pliers or a similar tool.
   
2. Turn the pump upside down.
3. Check that all loose parts fall out of the pump.
   The non-return valve can be fitted in a Grundfos service workshop.

Fitting the cable plug to the motor

Electric shock
Death or serious personal injury

• Do not remove the motor plug.
• The cable with plug must be fitted or removed by an authorised Grundfos service workshop or a similarly qualified person.

To fit the cable plug, proceed as follows:

1. Make sure of the proper type, cross section andlength of the cable.
2. Make sure that the cable plug is greased correctly.
3. Make sure the power supply is properly earthed.
4. Make sure the motor socket is clean and dry, andthat the loose gasket has been fitted.
5. Press the cable plug onto the motor socket.
   Fitting the cable plug onto the motor socket
   
6. Fit and tighten the four screws (3.5 Nm).
   Make sure there is no clearance between the motor and the cable plug.

Storage

Storage temperature: -20°C to +60°C.

Frost protection

Make sure that the pump is stored in a frost free location and that the motor liquid is frost proof.
Do not store the pump without motor liquid in it.

Fault finding

Electric shock
Death or serious personal injury

• Before starting any work on the product, make sure that the power supply has been switched off and that it cannot be accidentally switched on.

The pump does not run

The pump runs but gives no water

The pump runs at reduced capacity

Frequent starts and stops

Megging

Do not meg an installation incorporating this product as the built-in electronics may be damaged.
Megging

Tests not allowed

Do not use insulation or high voltage testers.


Use a true RMS instrument.

Checking the power supply

Electric shock
Death or serious personal injury

• Before starting any work on the product, make sure that the power supply has been switched off and that it cannot be accidentally switched on.

1. Supply voltage
   Measure the voltage (RMS) between phase and neutral. Connect the voltmeter to the terminals at the connection.
   The voltage should be 1 × 200-240 V -10% / +6%, 50/60 Hz, PE, when the motor is loaded. Large variations in supply voltage indicate poor power supply, and the pump should be stopped until the defect has been remedied.
   

   Pos.	Description
   1	L
   2	N
   3	PE

2. Current consumption
   Measure the current (RMS) while the pump is operating at a constant discharge head (if possible, at the capacity where the motor is most heavily loaded). For maximum current, see nameplate.
   

Technical data

Supply voltage
1 × 200-240 V -10% / +6%, 50/60 Hz, PE.
Operation via generator: As a minimum, the generator output must be equal to the motor P1 [kW] + 50%.

Starting current
The motor starting current is equal to the highest value stated on the motor nameplate.

Power factor
PF = 1.

Motor liquid
Type SML 3.

Motor cable
1.5 m, 3 × 1.5 mm², PE.

Liquid temperature
Maximum 35°C.

Pump outlet size
SQ 1, SQ 2, SQ 3: Rp 1 1/4.
SQ 5, SQ 7: Rp 1 1/2.

Pump diameter
74 mm.

Borehole diameter
Minimum 76 mm.

Installation depth
Maximum 150 m below static water level.

Net weight
Maximum 6.5 kg.

Sound pressure level

The sound pressure level of the pump is lower than the limiting values stated in the EC Council Directive 2006/42/EC relating to machinery.

Nameplates to be filled in