Grundfos SQ Series User manual

SQ, SQE
GRUNDFOS INSTRUCTIONS
Installation and operating instructions

LIMITED WARRANTY
Products manufactured by GRUNDFOS PUMPS CORPORATION (Grundfos) are
warranted to the original user only to be free of defects in material and workmanship
for a period of 24 months from date of installation, but not morethan 30 monthsfrom
date of manufacture. Grundfos' liability under this warranty shall be limited to repair-
ing or replacing at Grundfos' option, without charge, F.O.B. Grundfos' factory or
authorized service station, any product of Grundfos' manufacture. Grundfos will not
be liable for any costs of removal, installation, transportation, or any other charges
which may arise in connection with a warranty claim. Products which are sold but
not manufactured by Grundfos are subject to the warranty provided by the manu-
facturer of said products and not by Grundfos' warranty. Grundfos will not be liable
for damage or wear to products caused by abnormal operating conditions, accident,
abuse, misuse, unauthorized alteration or repair, or if the product was not installed
in accordance with Grundfos' printed installation and operating instructions.
To obtain service under this warranty, the defective product must be returned to the
distributor or dealer of Grundfos' products from which it was purchased together
with proof of purchase and installation date, failure date, and supporting installation
data. Unless otherwise provided, the distributor or dealer will contact Grundfos or
an authorized service station for instructions. Any defective product to be returned
to Grundfos or a service station must be sent freight prepaid; documentation sup-
porting the warranty claim and/or a Return Material Authorization must be included
if so instructed.
GRUNDFOS WILL NOT BE LIABLE FOR ANY INCIDENTAL OR CONSEQUEN-
TIAL DAMAGES, LOSSES, OR EXPENSES ARISING FROM INSTALLATION,
USE, OR ANY OTHER CAUSES. THERE ARE NO EXPRESS OR IMPLIED WAR-
RANTIES, INCLUDING MERCHANTABILITY OR FITNESS FOR A PARTICULAR
PURPOSE, WHICH EXTEND BEYOND THOSE WARRANTIES DESCRIBED OR
REFERRED TO ABOVE.
Some jurisdictions do not allow the exclusion or limitation of incidental or conse-
quential damages and some jurisdictions do not allow limit actions on how long
implied warranties may last. Therefore, the above limitations or exclusions may not
apply to you. This warranty gives you specific legal rights and you may also have
other rights which vary from jurisdiction to jurisdiction.
2

3
SQ, SQE
Installation and operating instructions 4
Notice d’installation et d’entretien 13
Instrucciones de instalación y funcionamiento 24

4
CONTENTS Page
1. General description 4
1.1 Applications 4
2. Preinstallation 4
2.1 Well preparation 4
2.2 Make sure you have the right pump 4
2.3 Pumped liquid requirements 4
2.4 Liquid temperatures/cooling 4
2.5 Motor preparation 5
2.6 Refilling of motor liquid 5
3. Installation positions 5
3.1 Positional requirements 5
4. Electrical connection 6
4.1 General 6
4.2 Motor protection 6
4.3 Connection of motor 6
5. Cable sizing 7
6. Splicing the cable 7
7. Fitting the cable guard 7
8. Piping 7
9. Installing the pump 8
9.1 Installation depth 8
10. Generator operation 8
11. Starting the pump for the first time 8
11.1 Motor cooling and other considerations 8
11.2 Impurities in the water 9
11.3 Minimum flow rate 9
11.4 Built-in functions 9
11.5 Resetting the pump 9
11.6 MS 3 motors 9
11.7 MSE 3 motors 9
11.8 Maintenance and service 9
12. Assembly of pump and motor 9
13. Troubleshooting 10
13.1 Instruments not allowed 11
14. Checking of motor and cable 11
15. Environment 11
16. Technical data 12
17. Disposal 12
1. General description
The SQ/SQE is a 3 inch diameter deep well sub-
mersible pump mainly designed for the pumping of
raw water in domestic water supply.
This manual is designed to assist in the proper set-
up, installation and operation of these pumps.
1.1 Applications
Typical applications:
• residential housing
• small waterworks
• pressure boosting
• liquid transfer in tanks
• irrigation systems.
WARNING: This pump has not been investigated for
use in swimming pool or marine areas.
2. Preinstallation
2.1 Well preparation
If the pump is to be installed in a new well, the well
should be fully developed and bailed or blown free of
cuttings and sand.
The construction of the Grundfos SQ/SQE submersi-
bles makes them resistant to abrasion; however, no
pump made of any material can forever withstand the
destructive wear that occurs when constantly pump-
ing sandy water.
If this pump is used to replace an oil-filled submers-
ible or oil-lubricated line-shaft turbine in an existing
well, the well must be blown or bailed clear of oil.
2.2 Make sure you have the right pump
Determine the maximum depth of the well and the
drawdown level at the maximum pump capacity.
Pump selection and setting depth should be made
based on this data.
2.3 Pumped liquid requirements
Submersible well pumps are designed for pumping
clear, cold water; free of air or gases. Decreased
pump performance and life expectancy can occur if
the water is not clear, cold or contains air or gases.
A check should be made to ensure that the installa-
tion depth of the pump will always be at least three
feet below the maximum drawdown level of the well.
The bottom of the motor should never be installed
lower than the top of the well screen or within five
feet of the well bottom.
CAUTION: This pump has been approved for pump-
ing maximum 86°F water only.
2.4 Liquid temperatures/cooling
Figure 1 shows an SQ/SQE pump installed in a well.
With the pump operating, figure 1 illustrates the fol-
lowing:
• Well diameter
• Pump diameter
• Temperature of pumped liquid
• Flow past the motor to the pump suction strainer.
Note: The well diameter must be at least 3 inches.
If there is a risk that the motor will be covered with
sediment, it is recommended the pump be placed in
a flow sleeve. The motor should always be installed
above the well screen.
WARNING:
Prior to installation, read these installation
and operating instructions. Installation and
operation must comply with local regula-
tions and accepted codes of good prac-
tice.

5
Fig. 1 Pump installed in well
2.5 Motor preparation
Grundfos MS 3 and MSE 3 submersible motors have
water-lubricated slide bearings. No additional lubri-
cation is required.
The submersible motors are factory-filled with a spe-
cial Grundfos motor liquid, type SML 2 or SML 3,
which will protect the motor liquid down to 4°F
(–20°C) and prevent the growth of bacteria. The
level of motor liquid is important for the operating life
of the bearings and consequently the life of the
motor.
2.6 Refilling of motor liquid
If for any reason the motor liquid has been drained or
lost, the motor must be refilled with Grundfos motor
liquid SML 2 or SML 3.
To refill the motor, proceed as follows:
1. Remove the cable guard and separate the pump
end from the motor.
2. Place the motor in vertical position with an incli-
nation of approximately 10°.
3. Remove the filling plug using a screwdriver or a
similar tool.
4. Inject motor liquid into the motor with a filling
syringe or similar tool, see fig. 2.
5. To allow possible air to escape, move the motor
from side to side and turn the shaft.
6. Replace the filling plug and make sure it is tight.
7. Assemble pump end and motor.
8. Fit the cable guard.
The pump is now ready for installation.
Fig. 2 Injecting motor liquid
3. Installation positions
3.1 Positional requirements
The pump is suitable for vertical as well as horizontal
installation, however, the pump shaft must never fall
below the horizontal plane, see fig. 3.
If the pump is to be installed horizontally, e.g. in a
tank, and there is a risk that the pump might be
covered by mud, it must be installed in a flow sleeve.
Fig. 3 Pump position
TM01 0518 1297
Well
diameter
Pump
diameter
Liquid
temperature,
max. 86°F
TM02 9606 3504TM01 1375 4397
10
Allowed
Not allowed

6
4. Electrical connection
4.1 General
The electrical connection should be carried out by
an authorized electrician in accordance with local
regulations.
The supply voltage, rated maximum current and
power factor (PF) appear on the motor nameplate.
The required voltage for Grundfos submersible MS 3
and MSE 3 motors, measured at the motor terminals,
is –10%/+6% of the nominal voltage during continu-
ous operation (including variation in the supply volt-
age and losses in cables).
If the pump is connected to an installation where a
Ground Fault circuit breaker (GFI) is used as addi-
tional protection, this circuit breaker must trip out
when ground fault currents with DC content
(pulsating DC) occur.
Supply voltage
1 x 100-115 V or 1 x 200-240 V, 50/60 Hz.
The current consumption can only be measured
accurately by means of a true RMS instrument.
If other instruments are used, the value measured
will differ from the actual value.
The SQE pumps can be connected to a CU 300 or
CU 301 control box.
4.2 Motor protection
The motor has built-in automatic thermal overload
protection and requires no additional motor protec-
tion.
4.3 Connection of motor
The motor can be connected directly to the main
circuit breaker.
Start/stop of the pump will typically be done via a
pressure switch, see figs. 4 and 5.
Note: The pressure switch must be rated for the
maximum amps of the specific pump.
Fig. 4 Wiring diagram for 2-wire Grundfos
motors (200-240 V)
Fig. 5 Wiring diagram for single-phase Grundfos
motors (100-115 V)
WARNING:
Before starting work on the pump, make
sure that the electricity supply has been
switched off and that it cannot be acciden-
tally switched on.
This pump is permanent wiring connection
only.
Reduced risk of electric shock during
operation of this pump requires the provi-
sion of acceptable grounding.
The grounding connection must be made
by a copper conductor, at least the size of
the circuit conductors supplying the pump.
The pump must be connected to an exter-
nal mains switch.
The pump must never be connected to a
capacitor or to another type of control box
than CU 300 or CU 301.
The pump must never be connected to an
external frequency converter.
WARNING:
Reduced risk of electric shock during
operation of this pump requires the provi-
sion of acceptable grounding. If the means
of connection to the supply connected box
is other than grounded metal conduit,
ground the pump back to the service by
connecting a copper conductor, at least
the size of the circuit conductors supplying
the pump.
TM02 8736 0804TM02 8736 0804
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Quickdisconnection
Pressure
switch Black
Black
Green
Pump and motor
L1
L2
G
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L
N
G
Quick disconnection
Pressure
switch Black
White or grey
Green
Pump and motor

7
5. Cable sizing
Single-phase 60 Hz maximum cable length motor service to entrance:
Note: The values apply to 230 V, 60 Hz, and conform to the requirements stated in the National Electrical
Code Book.
Note: Recommended maximum cable length between the SQE and the CU 300 or CU 301 control box = 650 ft.
6. Splicing the cable
Splice the drop cable with the motor cable.
The splice must be made carefully.
It is recommended to use a third-party-approved
watertight junction box or splice connection.
7. Fitting the cable guard
To fit the cable guard, proceed as follows:
1. Make sure that the motor lead lies flat in the
cable guard.
2. Place the cable guard in the groove in the cable
plug. The two flaps must engage with the upper
edge of the pump sleeve, see fig. 6.
Fig. 6 Placing the cable guard
3. Fasten the cable guard to the pump suction
strainer with the two self-tapping screws sup-
plied, see fig. 7.
Fig. 7 Fitting the cable guard to the pump
suction strainer
8. Piping
• The pump should only be gripped by the two flats
at the top of the pump, see fig. 8.
• The pump can be installed vertically or horizon-
tally. During operation, the pump must always be
completely submerged in water.
• When plastic pipe is used, a stainless-steel safety
wire is recommended for lowering and lifting the
pump. Fasten the wire to the eyelet on the pump,
see fig. 9.
• The threaded joints must be well cut and fit
together tightly to ensure that they do not work
loose.
Fig. 8 Gripping the pump
Motor rating Maximum lengths of copper wire in feet (9% voltage drop)
Volts hp amps 14 AWG 12 AWG 10 AWG 8 AWG 6 AWG 4 AWG 2 AWG
115 0.5 12 140 220 360 550 880 1390 2260
230 0.5 5.2 640 1000 1660 2250 4060 – –
230 0.75 8.4 400 620 1030 1580 2510 3970 –
230 1.0 11.2 300 460 770 1190 1890 2980 4850
230 1.5 12 280 430 720 1110 1760 2780 4530
TM02 9613 3504
TM01 4427 0299TM02 8739 0804

8
9. Installing the pump
9.1 Installation depth
The dynamic water level should always be above
the pump, see fig. 9.
A = Dynamic water level
B = Static water level
C = Minimum 3 inch well diameter
D = Drawdown
E = Installation depth below static water level.
Maximum 500 feet.
Fig. 9 Installation depth
Procedure
To install the pump, proceed as follows:
1. Attach the enclosed data plate sticker at the well
head.
2. Check the well for proper clearance. The well
must be at least 3 inches in diameter.
It is a good idea to check the well for clearance
using a plumb ring (2.95 ø x 10 in.).
3. Attach the first section of riser pipe to the pump.
4. Lower the pump into the well. Make sure the
motor cable is not damaged when the pump is
lifted or lowered into the well, especially in 3 inch
wells.
Note: Do not lower or lift the pump using the
motor cable.
5. When the pump has been installed to the
required depth, the installation should be finished
by means of a well seal.
Note that the dynamic water level should always
be above the pump.
6. Loosen the safety wire so that it becomes
unloaded and lock it to the well seal using a cable
clamp.
7. Complete the electrical connections.
Note: The pump must never be connected to a
capacitor or to another type of control box than
CU 300 or CU 301.
Installation depths
Maximum installation depth:
500 feet below the static water level.
Minimum installation depth:
1.75 feet 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 at least 1.75 feet below
the dynamic water level.
If there is a risk that the pump might be covered by
mud, the pump must always be placed in a flow
sleeve.
Note: Do not lower or lift the pump using the motor
cable.
10. Generator operation
It is safe to operate the SQ/SQE with a generator.
The generator must be sized 50% above the P1
(input power) values of the pump. See the following
table.
11. Starting the pump for the first time
When the pump has been connected correctly, the
pump should be started with the discharge valve
closed approximately one third.
Due to the soft start feature, the pump takes approxi-
mately 2 seconds to develop full pressure.
11.1 Motor cooling and
other considerations
• Make sure the well is capable of yielding a mini-
mum quantity of water corresponding to the pump
capacity.
• Do not start the pump until it is completely sub-
merged in the liquid.
• As the valve is being opened, the drawdown
should be checked to ensure that the pump
always remains submerged.
TM02 8740 0804
AB
D
C
E
Motor
[hp]
Min.
generator size
[W]
Recommended
generator
output [W]
0.5 1200 1500
0.75 1900 2500
1.0 2600 3200
1.5 2800 3500

9
• To ensure the necessary cooling of the motor, the
pump should never be set so low that it gives no
water.
If the flow rate suddenly falls, the reason might be
that the pump is pumping more water than the well
can yield. The pump must immediately be stopped
and the fault corrected.
11.2 Impurities in the water
If there are impurities in the water, the valve should
be opened gradually as the water becomes clearer.
The pump should not be stopped until the water is
clean, otherwise the pump parts and the check valve
may become clogged.
When the water is clean, the valve should be fully
opened.
11.3 Minimum flow rate
To ensure the necessary cooling of the motor, the
pump flow rate should never be set to a value lower
than 0.2 gpm.
If the flow rate suddenly falls, the reason might be
that the pump is pumping more water than the well
can yield. The pump must immediately be stopped
and the fault corrected.
WARNING: The pump's dry-running protection is
effective only within the recommended duty range of
the pump.
Note: Do not let the pump run against a closed dis-
charge valve for more than 5 minutes. When the dis-
charge valve is closed, there is no cooling flow and
there is a risk of overheating in motor and pump.
11.4 Built-in functions
The motor incorporates an electronic unit which
functions as follows:
• In case of overload, the built-in overload protec-
tion will stop the pump for 5 minutes. After that
period, the pump will attempt to restart.
• If the pump has been stopped as a result of dry
running, it will start automatically after 5 minutes.
• If the pump is restarted and the well has not
recovered, the pump will stop after 30 seconds.
11.5 Resetting the pump
Switch off the electricity supply for 1 minute.
11.6 MS 3 motors
Note: All MS 3 motors are factory-set to detect dry-
running conditions.
Check that the combination of pump and motor cor-
responds to the data on page 35.
11.7 MSE 3 motors
Note: All MSE 3 motors are factory-set to detect dry-
running conditions. However, if the maximum pump
speed setting is changed, the dry-running stop value
must also be changed. Please refer to either the
CU 300 or CU 301 I&O for instructions on this proce-
dure.
11.8 Maintenance and service
The pumps are normally maintenance-free.
Deposits and wear may occur.
For that purpose, service kits and service tools are
available from Grundfos.
The pumps can be serviced at a Grundfos service
center.
12. Assembly of pump and motor
To assemble pump end and motor, proceed as
follows:
1. Place the motor horizontally in a vice and tighten
it, see fig. 11.
2. Pull the pump shaft out to the position shown in
fig. 10.
Fig. 10 Pump shaft position
3. Grease the motor shaft end with the grease
supplied with the motor.
4. Screw the pump end on the motor (55 Nm).
Note: The pump shaft must engage with the
motor shaft.
A spanner may be used on the clamping faces of
the pump end, see fig. 11.
5. Fit the cable guard as described in section 7.
Fig. 11 Pump in vice
0.5 hp: L = 4.7".
0.75 hp: L = 4.0".
1.0 hp: L = 2.6".
1.5 hp: L = 2.6".
When pump end and motor have been assembled
correctly, there must be no clearance between pump
end and motor.
To disassemble, reverse procedure.
TM02 8425 5203
TM01 2854 3804
L
Use pump vice here
6.14"

10
13. Troubleshooting
Fault Cause Remedy
1. The pump does
not run. a) The fuses are blown. Replace the blown fuses. If the new fuses blow too, check the electrical installation
and the drop cable.
b) The GFI circuit breaker has tripped. Reset the circuit breaker.
c) No electricity supply. Contact the electricity provider.
d) The motor protection has cut off the
electricity supply due to overload. Check for motor/pump blockage.
e) The drop cable is defective. Repair or replace the pump/cable.
f) Overvoltage has occurred. Check the electricity supply.
2. The pump runs but
gives no water. a) The discharge valve is closed. Open the valve.
b) No water or too low water level in
well. Increase the installation depth of the pump, throttle the pump or replace it with a smaller
capacity model.
c) The check valve is stuck in its
closed position. Pull the pump and clean or replace the valve.
d) The suction strainer is closed. Pull the pump and clean the strainer.
e) The pump is defective. Repair or replace the pump.
3. The pump runs at
reduced capacity. a) The drawdown is larger than antici- pated. Increase the installation depth of the pump, throttle the pump or replace it with a smaller
capacity model.
b) The valves in the discharge pipe are
partly closed/blocked. Check and clean or replace the valves as necessary.
c) The discharge pipe is partly choked
by impurities (iron bacteria). Clean or replace the discharge pipe.
d) The check valve of the pump is
blocked. Pull the pump and clean or replace the valve.
e) The pump and the riser pipe are
partly choked by impurities
(iron bacteria).
Pull the pump. Check and clean or replace
the pump, if necessary. Clean the pipes.
f) The pump is defective. Repair or replace the pump.
g) Hole in discharge pipe. Check and repair the piping.
h) The riser pipe is defective. Replace the riser pipe.
i) Undervoltage has occurred. Check the electricity supply.
4. Frequent starts
and stops. a) The differential of the pressure switch between the start and stop
pressures is too small.
Increase the differential. However, the stop
pressure must not exceed the operating
pressure of the pressure tank and the start
pressure should be high enough to ensure
sufficient water supply.
b) The water level electrodes or level
switches in the reservoir have not
been installed correctly.
Adjust the intervals of the electrodes/level
switches to ensure suitable time between
the cutting-in and cutting-out of the pump.
See installation and operating instructions
for the automatic devices used. If the inter-
vals between start/stop cannot be changed
via the automatics, the pump capacity may
be reduced by throttling the discharge
valve.
c) The check valve is leaking or stuck
half-open. Pull the pump and clean or replace the check valve.
d) The supply voltage is unstable. Check the electricity supply.
e) The motor temperature is too high. Check the water temperature.