Grundfos S2 Series User manual

S pumps, ranges 72-74-78
S2, S3, S4, ST
55-520 kW
Installation and operating instructions
GRUNDFOS INSTRUCTIONS

English (GB)
2
English (GB) Installation and operating instructions
Original installation and operating instructions.
CONTENTS
Page
1. Symbols used in this document
2. General description
This booklet includes instructions for installation, operation and
maintenance of Grundfos submersible sewage and wastewater
S-range pumps with motors of 55 to 520 kW.
Fig. 1 S pump, range 72
1. Symbols used in this document 2
2. General description 2
2.1 Applications 3
2.2 Potentially explosive environments 3
2.3 Operating conditions 4
2.4 Sound pressure level 4
3. Identification 5
3.1 Type key 5
3.2 Nameplates 6
3.3 Approval plates, range 72 6
3.4 Ex certification and classification 6
4. Safety 7
5. Transportation and storage 7
5.1 Lifting the pump 7
5.2 Raising pump to upright position 9
5.3 Storage 10
6. Installation 10
6.1 Installation types 10
6.2 Start and stop levels 12
6.3 Submerged installation on auto-coupling 12
6.4 Column pipe installation 12
6.5 Dry installation 13
7. Motor protection 14
7.1 IO 113 14
7.2 SM 113 14
7.3 Switches and sensors 14
8. Electrical connection 16
8.1 Cross-sections for power cables 16
8.2 Wiring diagram for sensors 17
8.3 Frequency converter operation 17
9. Startup 18
9.1 Checking the direction of rotation 18
10. Maintenance and service 19
10.1 Oil check and oil change 19
10.2 Inspection and adjustment of impeller clearance 20
10.3 Contaminated pumps 22
11. Fault finding chart 23
12. Disposal 23
Warning
Prior to installation, read these installation and
operating instructions. Installation and operation
must comply with local regulations and accepted
codes of good practice.
Warning
If these safety instructions are not observed,
it may result in personal injury.
Warning
These instructions must be observed for
explosion-proof pumps. We recommend that you
also follow these instructions for standard
pumps.
Warning
If these instructions are not observed, it may lead
to electric shock with consequent risk of serious
personal injury or death.
Warning
The surface of the product may be so hot that
it may cause burns or personal injury.
Warning
The sound pressure level is so high that hearing
protection must be used.
Caution
If these safety instructions are not observed,
it may result in malfunction or damage to the
equipment.
Note
Notes or instructions that make the job easier
and ensure safe operation.
TM03 1507 1110
Pos. Description
1 Inlet
2Outlet
3 Power supply cables
4 Control cable
5 Lifting bracket
6 Terminal box
7 Submersible motor
8Pump
17 Air vent valve

English (GB)
3
2.1 Applications
S pumps, range 72, 74 and 78, are designed for the pumping of
sewage and wastewater in a wide range of municipal and
industrial applications.
Depending on the installation type, the pumps can be used for
submerged or dry, horizontal or vertical, installation.
Maximum solids size: 90-145 mm, depending on impeller type.
2.2 Potentially explosive environments
In potentially explosive environments, use only Ex-approved
apparatus. All range-72 pumps are available as Ex versions.
Range 72 Ex pumps can be used in hazardous areas classified
as Zone 1 or Zone 2.
Warning
Special conditions for safe use of S pumps,
range 72 Ex, 74 and 78:
1. Make sure the moisture switches and thermal
switches are connected in two separate circuits
and have separate alarm outputs (motor stop) in
case of high humidity or high temperature in the
motor.
2. Bolts used for replacement must be class A4-80
or A2-80 according EN/ISO 3506-1.
3. The flame path gaps of the motor are specified by
the manufacturer and are narrower than
standard. Please see the manufacturer's
installation, operation and maintenance
document for guidance.
4. During operation, the cooling jacket, when fitted,
must be filled with pumped liquid.
5. The level of pumped liquid must be controlled by
level switches connected to the motor control
circuit. The minimum level depends on the
installation type and is specified in these
installation and operating instructions.
6. Dry-running is not allowed.
7. Make sure the permanently attached cables are
suitably mechanically protected and terminated in
a suitable terminal board.
8. The sewage pumps have an ambient temperature
range of 0-40 °C and a maximum process
temperature 40 °C.
9. The control unit must protect the WIO against the
short circuit current of the supply to which it is
connected. The maximum current from the
control unit must be limited to 350 mA.
10.The maximum submersion depth is 20 m.
Warning
Special conditions for safe use of WIO sensor
1. The control unit must protect the sensor against
the short-circuit current of the current supply to
which it is connected.
2. The sensor must be installed in such a way that
danger of mechanical impact is avoided.
3. The WIO sensor must not be used in oil with a
flash point below 250 °C.
4. The WIO sensor is approved according to
EN/IEC 60079-18:2004. In Ex and IEC Ex
applications, the maximum current supplied to the
sensor must be limited to 350 mA according to
EN/IEC 60079-18:2004.
Installation
type Description Accessories
S
Sewage pump without
cooling jacket for
submerged installation on
auto coupling.
Auto coupling
C
Sewage pump with
cooling jacket for
submerged installation on
auto coupling.
Auto coupling
D
Sewage pump with
cooling jacket for dry
vertical installation.
Base plate for vertical
installation
H
Sewage pump with
cooling jacket for dry
horizontal installation.
Base plate for
horizontal installation
ST
Sewage pump without
cooling jacket for
installation in vertical
column pipe.
Seat ring
Note
Ranges 74 and 78 are not available with Ex
approval.

English (GB)
4
2.3 Operating conditions
pH value
All pumps can be used for pumping liquids with a pH value
between 4 and 10.
Liquid temperature
The allowed temperature is 0-40 °C.
Ambient temperature
The allowed temperature is 0-40 °C.
Density and viscosity of pumped liquid
Density: 1000 kg/m3.
Kinematic viscosity: 1 mm2/s (1 cSt).
2.3.1 Installation depth
The maximum submersion depth is 20 m.
2.3.2 Level of pumped liquid
To avoid air being sucked into the pump and to ensure adequate
cooling of the motor during operation, the following minimum
requirements must be met:
•Installation type S:
For S1 operation (continuous operation), the pump must
always be covered by the pumped liquid to the top of the
motor. See fig. 2. See also section 9.1 Checking the direction
of rotation.
•Installation type C:
The pump housing must always be covered by the pumped
liquid.
Fig. 2 Stop levels
•Installation types D and H:
See section 6.5 Dry installation.
•Installation type ST:
The liquid level must be at least 900-1100 mm above the pump
inlet. See fig. 21.
2.3.3 Pressure version
See section 4. Safety.
2.3.4 Operating mode
The pumps are designed for continuous operation with the
maximum number of starts per hour stated in the table below:
2.3.5 Enclosure class
IEC IP68.
2.4 Sound pressure level
Note
In special situations the temperature of the
pumped liquid may be higher, if the motor is not
fully loaded.
If necessary, contact the nearest Grundfos
company or service workshop.
Warning
Explosion-proof pumps must never pump liquids
with a temperature higher than 40 °C.
Note
In special situations the ambient temperature
may be higher, if the motor is not fully loaded.
If necessary, contact the nearest Grundfos
company or service workshop.
Warning
For explosion-proof pumps, the ambient
temperature on the installation site must be in
the range between 0 and 40 °C.
Note
When pumping liquids with a density and/or a
kinematic viscosity higher than the values stated
above, use motors with correspondingly higher
outputs.
Warning
An Ex motor must always be fully submerged
during operation.
Warning
Install an additional level switch to ensure that
the pump is stopped in case the stop level switch
is not operating.
Warning
Installation type S and C pumps must always be
fully submerged in the pumped liquid to be Ex
protected.
Note
For installation type C pumps, the air vent valve
must always be open, also during operation.
See fig. 1.
Installation types C and S
TM03 1626 0208
Warning
During operation, the cooling jacket must be
filled with pumped liquid to ensure sufficient
cooling. Before the first startup and after long
standstill periods, the air must be evacuated from
the cooling jacket through an air-vent valve.
S pump, range Starts per hour
72 15
74 and 78 10
Warning
Depending of the installation type the sound
pressure level of the pump can be higher than
70 dB (A). Use hearing protection when working
nearby such an installation in operation.
Ex pumps,
installation type S
Installation type C

English (GB)
5
3. Identification
3.1 Type key
All S pumps, ranges 72, 74 and 78, described in this booklet are identified by the type designation stated in the confirmation of order and
other documentation supplied with the pump.
Please note that the pump type described in this booklet is not necessarily available in all variants.
Code Example S 2 .90 .250 .2250 .4 .72 S .C .496 .G .N .D .5 13 .Z
S
ST
Pump type:
Grundfos sewage and wastewater pump
Multi-channel impeller pump installed in a column pipe
2
3
4
Impeller type:
Two-channel
Three-channel
Four-channel
Pump passage:
Maximum solids size [mm]
250
[ ]
Pump discharge, S-type:
Nominal diameter of pump discharge port [mm]
Pump discharge, ST-type:
Nominal diameter of column pipe [mm]
Output power, P2:
P2 = Code number from type designation / 10 [kW]
4
6
8
10
12
14
Number of poles:
4-pole motor
6-pole motor
8-pole motor
10-pole motor
12-pole motor
14-pole motor
72
74
78
Pump range:
Range 72
Range 74
Range 78
S
H
M
L
E
F
Pressure version:
Super high
High
Medium
Low
Extra low
Super low
S
C
D
H
Installation type:
Submerged installation without cooling jacket
Submerged installation with cooling jacket
Dry installation with cooling jacket
Dry horizontal installation with cooling jacket
Impeller diameter (mean):
[mm]
G
Q
Material code for impeller, pump housing and stator housing:
Cast iron impeller, pump housing and stator housing
Stainless steel impeller, DIN W.-Nr. 1.4408
N
Ex
Pump version:
Non-explosion-proof pump
Pump with explosion-proof motor
B
D
Sensor version:
S pump with built-in SM 113 module. PTC sensors are connected directly to IO 113 or other PTC relay.
S pump without built-in SM 113 module
5
6
Frequency:
50 Hz
60 Hz
11
13
18
1G
1B
1D
11
1G
1H
Voltage and connection:
50 Hz
3 x 400 / 690 V Y/D
3 x 415 / 719 V Y/D
3 x 380-400 / 660-690 V Y/D
3 x 380 / 660 V Y/D
3 x 400-415 / 690-719 V Y/D
3 x 380-415 / 660-719 V Y/D
60 Hz:
3 x 575 / (996) V Y/D
3 x 380 / 660 V Y/D
3 x 460 / (797) V Y/D
Z Custom-built products

English (GB)
6
3.2 Nameplates
Fig. 3 Pump nameplate
3.3 Approval plates, range 72
Fig. 4 Approval plates of explosion-proof S-pumps, range 72
The approval plate gives the following details:
3.4 Ex certification and classification
The range 72 Ex-pumps have an EC-type Examination Certificate
issued by Baseefa Ltd.
The certified pumps (Ex-pumps) are supplied with an approval
plate fixed in a visible place close to the nameplate.
Figure 4shows the approval plates for range 72 pumps equipped
optionally with the motors classified to T3 or T4 temperature
class.
TM06 1781 2514 - TM06 0370 5313
Pos. Description
1 Type designation
2 Product number
3 Serial number
4 Maximum head [m]
5 Maximum installation depth [m]
6 Number of phases
7 Voltage, delta connection
8 Voltage, star connection
9 Rated power input [kW]
10 Power factor
11 Production code [YYWW]
12 Production number
13 Maximum liquid temperature [°C]
14 Maximum flow rate [l/s]
15 Enclosure class
16 Frequency [Hz]
17 Rated speed
18 Current, delta connection
19 Current, star connection
20 Rated power output P2
21 Insulation class
22 Weight
23 Place of production
1
2
3
4
5
6
7
8
9
10
11
12
23
13
14
15
16
17
18
19
20
21
22
12
22
23
TM06 0916 1214 - TM06 0917 1214
CE CE mark
Baseefa 1180 ATEX-notified body identification number
EU ex symbol
II Equipment group (II = non-mining)
2 Equipment category (high protection)
G Type of explosive atmosphere (G = Gas)
Ex Explosion-proof motor according to European
standard
b Control of ignition sources
c Constructional safety
d Flameproof
IIB Gas group (Ethylene)
T3 Maximum surface temperature of the motor is
200 °C
T4 Maximum surface temperature of the motor is
135 °C
Baseefa Certificate number
Type 72X2254 (example)
No. Serial number
PC Production code (year/week)
72
Direct drive, 50 or 60 Hz CE 1180 II 2 G Ex bcd IIB T4
Frequency converter
drive CE 1180 II 2 G Ex bcd IIB T3

English (GB)
7
4. Safety
For safety reasons, all work in pits must be supervised by a
person outside the pump pit.
Pits for submersible sewage and wastewater pumps contain
sewage and wastewater with toxic and/or disease-causing
substances. Therefore, all persons involved must wear
appropriate personal protective equipment and clothing, and all
work on and near the pump must be carried out under strict
observance of the hygiene regulations in force.
5. Transportation and storage
The pump is supplied from factory on a steel transportation stand
in horizontal position. Pump and stand is protected by a special
cover.
Fig. 5 Covered pump in transportation stand
The pump is equipped with a label indicating the centre of gravity
of the pump including installation/transportation accessories.
See fig. 5. The position of the label varies depending on pump
type and accessories.
Fig. 6 Symbol of centre of gravity
Fig. 7 Transportation stand with cable holders
5.1 Lifting the pump
S pumps, range 78 weigh up to 8100 kg without accessories.
It is therefore very important to use the right lifting equipment.
The pump weight is stated on the pump nameplate.
See section 3.2 Nameplates.
Warning
Pump installation in pits must be carried out by
specially trained persons.
Work in or near pits must be carried out
according to local regulations.
Warning
It must be possible to lock the main power switch
in position 0. Type and requirements as specified
in EN 60204-1, 5.3.2.
Warning
Persons must not enter the installation area
when the atmosphere is explosive.
Warning
Never work under a pump when it is hanging
from crane!
Warning
Before attempting to lift the pump, make sure the
rated capacity of the lifting equipment (lifting
chain etc.) is adequate for the lifting work.
The rated capacity of the lifting equipment is
stated on the equipment nameplate. The weight
of the pump is stated on the pump nameplate.
Warning
For some installation types, the surface
temperature may be up to 90 °C.
Warning
The surface temperature of the cables may
exceed 70 °C.
TM03 3069 4809
Note
We recommend that you keep the transportation
stand in storage for later use.
TM04 6728 0810TM03 3365 4809
Note
The weight is stated with 10 m cables.
Note
The weights of installation type S and C pumps
include the weight of the guide claw.
The weight of installation type H pumps includes
the weight of the horizontal base stand.

English (GB)
8
Pump type
Net weight [kg]
SCDH
Range 72
S2.90.250.2250.4.72S 1770 1950 1955 2250
S2.100.250.2250.4.72H 1760 1945 1955 2240
S2.100.250.1750.4.72H 1760 1945 1955 2240
S2.100.300.2250.4.72M 1840 2020 2010 2300
S2.100.300.1750.4.72M 1840 2020 2010 2300
S3.110.300.1800.6.72H 1965 2160 2150 2440
S3.110.300.1600.8.72H 1965 2165 2155 2445
S3.120.500.1800.6.72M 2335 2520 2360 2700
S3.120.500.1600.8.72M 2330 2530 2370 2700
S3.120.500.1250.8.72M 2330 2530 2370 2700
S3.135.500.1800.6.72L 2340 2525 2360 2700
S3.135.500.1600.8.72L 2335 2535 2375 2705
S3.135.500.1250.8.72L 2335 2535 2375 2705
S3.135.600.1600.8.72E 2710 2910 2690 3020
S3.135.600.1300.10.72E 2730 2930 2710 3040
S3.135.600.1100.10.72E 2720 2920 2700 3030
S3.135.600.900.10.72E 2710 2910 2690 3020
Range74 CDH
S2.90.300.2500.4.74S 2800 2800 3000
S2.90.300.3150.4.74S 3500 3500 3700
S2.100.300.2500.4.74H 2800 2800 3000
S2.100.300.3150.4.74H 3500 3500 3700
S3.110.300.2000.6.74H 3000 3000 3200
S3.110.300.2500.6.74H 3100 3100 3400
S3.110.300.3150.6.74H 3900 3900 4100
S3.120.300.2000.6.74M 3300 3200 3400
S3.120.300.2500.6.74M 3500 3300 3500
S3.120.300.3150.6.74M 4300 4100 4300
S3.135.500.2000.6.74L 3300 3300 3500
S3.135.500.2500.6.74L 3500 3400 3700
S3.135.500.3150.6.74L 4200 4200 4400
S3.135.600.2000.8.74E 3900 3700 4000
S3.135.600.2500.8.74E 4600 4400 4700
Range78 CDH
S3.115.500.3150.8.78H 5600 5500 6000
S3.115.500.3500.8.78H 6000 5800 6300
S3.115.500.4000.8.78H 6100 5900 6400
S3.115.500.4500.8.78H 6200 6000 6500
S3.115.500.5000.8.78H 6200 6100 6600
S3.115.500.5200.8.78H 6400 6200 6700
S3.130.500.2500.10.78M 5200 5100 5600
S3.130.500.3150.8.78M 5500 5400 5900
S3.130.500.3150.10.78M 5800 5600 6100
S3.130.500.3500.8.78M 5900 5800 6300
S3.130.500.3500.10.78M 6100 5900 6400
S3.130.500.4000.8.78M 6000 5900 6400
S3.130.500.4000.10.78M 6100 6000 6500
S3.130.500.4500.8.78M 6100 6000 6500
S3.130.500.5000.8.78M 6200 6100 6600
S3.130.500.5200.8.78M 6300 6200 6700
S3.145.500.1600.10.78L 5000 4900 5300
S3.145.500.2000.10.78L 5100 5000 5500
S3.145.500.2500.10.78L 5400 5300 5800
S3.145.500.3150.8.78L 5700 5600 6100
S3.145.500.3150.10.78L 5900 5800 6300
S3.145.500.3500.8.78L 6000 5900 6400
S3.145.500.3500.10.78L 6200 6100 6600
S3.145.500.4000.8.78L 6100 6000 6500
S3.145.500.5000.8.78L 6300 6200 6700
S3.145.500.5200.8.78L 6400 6300 6800
S4.135.600.1300.12.78E 5700 5700 6300
S4.135.600.1600.12.78E 5900 5900 6500
S4.135.600.2000.10.78E 5800 5800 6400
S4.135.600.2500.10.78E 6000 6000 6600
S4.135.600.3150.8.78E 6300 6300 6900
S4.135.600.3150.10.78E 6600 6600 7100
S4.135.600.3500.8.78E 6700 6700 7300
S4.135.600.4000.8.78E 6800 6800 7300
S4.135.600.4500.8.78E 6900 6900 7500
S4.135.600.5000.8.78E 7000 7000 7500
S4.135.600.5200.8.78E 7100 7100 7700
S4.155.800.2500.10.78F 6600 6500 7200
S4.155.800.3150.10.78F 7100 7000 7700
S4.155.800.3500.10.78F 7400 7300 8000
S4.155.800.4000.10.78F 7500 7400 8100
S4.155.800.1600.12.78F 6500 6400 7100
S4.155.800.2000.12.78F 7100 7000 7700
S4.155.800.2500.12.78F 7300 7200 8000
S4.155.800.1100.14.78F 6300 6200 6900
S4.155.800.1300.14.78F 6500 6400 7100
S4.155.800.1600.14.78F 7000 6900 7600
ST pumps Weight [kg]
Range 74
ST3.135.1200.2000.8.74E 2800
ST3.135.1200.2500.8.74E 3400
Range 78
ST4.135.1400.3150.8.78E 4700
ST4.135.1400.3500.8.78E 5000
ST4.135.1400.4000.8.78E 5100
ST4.135.1400.4500.8.78E 5200
ST4.135.1400.5000.8.78E 5300
ST4.135.1400.5200.8.78E 5400
ST4.135.1400.5200.8.78E 5400
ST4.135.1400.2000.10.78E 4200
ST4.135.1400.2500.10.78E 4400
ST4.135.1400.3150.10.78E 4900
ST4.135.1400.1300.12.78E 4100
ST4.135.1400.1600.12.78E 4300
ST4.155.1600.2500.10.78F 4700
ST4.155.1600.3150.10.78F 5200
ST4.155.1600.3500.10.78F 5500
ST4.155.1600.4000.10.78F 5500
ST4.155.1600.1600.12.78F 4600
ST4.155.1600.2000.12.78F 5200
ST4.155.1600.2500.12.78F 5400
ST4.155.1600.1100.14.78F 4400
ST4.155.1600.1300.14.78F 4600
ST4.155.1600.1600.14.78F 5100
Pump type
Net weight [kg]
SCDH

English (GB)
9
All lifting equipment must be rated for the purpose and checked
for damage before any attempt to lift the pump. The lifting
equipment rating must under no circumstances be exceeded.
The pump weight is stated on the pump nameplate.
Fig. 8 Lifting points on pump, range 72
Fig. 9 Lifting points on pump, range 74 and 78
5.2 Raising pump to upright position
Fig. 10 Raising the pump to upright position, step 1
Fig. 11 Raising the pump to upright position, step 2
Fig. 12 Raising the pump to upright position, step 3
Note
The weights are net weights including the
accessories mounted from factory.
Warning
Always lift the pump by the marked lifting points
or by means of a fork-lift truck.
To make the use of a fork-lift truck when moving
a pump safer, the approximate centre of gravity is
marked with a label attached to the
transportation stand. Make sure the centre of
gravity is between the fork-lift arms when lifting
the pump.
Never lift the pump by the power supply cables.
It may result in electric short-circuit and risk of
electric shock when the pump is connected to the
mains. The cables and cable entry may be
damaged, leading to loss of watertightness and
consequent severe damage to the motor.
TM03 4459 0208TM04 6068 4809
Warning
If during transportation, assembly or dismantling
the pump is tilted more than 10 ° in any direction
from its normal position (EN 809, 5.2.1.4), the
pump may lose its stability. Secure the pump by
means of chains or place it in horizontal position.
Warning
Make sure that the lifting brackets are tightened
before attempting to lift the pump. Tighten if
necessary. Carelessness during lifting or
transportation may cause injury to personnel or
damage to the pump.
TM03 3034 0208TM03 3035 0208TM03 3036 0208

English (GB)
10
5.3 Storage
For long periods of storage the pump must be protected against
moisture and heat.
Storage temperature: -20-55 °C. Maximum 70 °C for short
periods not exceeding 24 hours (EN 60204-1, 4.5).
After a long period of storage, inspect the pump before putting it
into operation. Make sure that the impeller can rotate freely.
Pay special attention to the condition of the shaft seals, O-rings
and the cable entry.
6. Installation
The extra nameplate supplied with the pump should be fixed at
the installation site.
All safety regulations must be observed at the installation site, for
instance the use of blowers for fresh-air supply to the pit.
Prior to installation, check the oil level in the oil chamber, see
section 10.1 Oil check and oil change.
6.1 Installation types
S pumps, ranges 72, 74 and 78 are designed for various
installation types.
Figures 13 to 20 show the possible installation types.
Installation types C and S
Submerged installation on auto-coupling.
Fig. 13 Permanent installation in pit
The pump can easily be pulled out and lowered into the pit by
means of the guide rails. The stop level is lower for type C than
for type S. See fig. 13.
Fig. 14 Upper guide rail bracket
Fig. 15 Intermediate guide rail bracket; required if guide rails
are more than 6 m long
Correct pedestal height for installation on auto-coupling is
important in order to obtain the best efficiency for the pump.
Fig. 16 Auto-coupling base installation on pedestal
Caution
Do not remove the protection hose from the free
end of the supply or sensor cables until the
electrical connection is to be made.
Whether insulated or not, the free cable end must
never be exposed to moisture or water.
Non-compliance with this may cause damage to
the motor.
Caution
If the pump is being stored for more than two
months, the impeller must be turned by hand at
least every two months to prevent the lower
mechanical seal faces from seizing up. If not, the
shaft seal may be damaged when the pump is
started. If the impeller cannot be turned by hand,
contact an authorized service workshop.
Caution
Make sure the cooling jacket is empty before
storing the pump.
Warning
During installation always support the pump by
means of lifting chains or place it in horizontal
position to secure stability.
Warning
Before beginning the installation, switch off the
power supply and lock the main power switch in
position 0.
Any external voltage connected to the pump
must be switched off before working on the
pump.
Warning
Do not put your hands or any tool into the pump
suction or discharge port after the pump has
been connected to the power supply, unless the
main power switch has been locked in the 0-
position.
Make sure that the power supply cannot be
accidentally switched on.
Warning
We recommend that you always use Grundfos
accessories to avoid malfunctions due to
incorrect installation.
TM03 1626 0208TM03 3066 0206TM03 3068 0206TM03 2018 0208
Installation type S
Stop levels
Installation type C

English (GB)
11
The correct pedestal heights (A) for installation on auto-coupling
appear from the following table.
Fig. 17 Lowering of pump onto auto-coupling
Installation type D
Permanent vertical dry installation.
Fig. 18 Permanent vertical dry installation
The dry-installed pumps are bolted to the suction and discharge
pipes by means of flange connections. See dimensions in
product-specific drawings.
Installation type H
Permanent horizontal dry installation.
Fig. 19 Permanent horizontal dry installation
Installation type ST
Installation in vertical column pipe
Fig. 20 Submerged installation in vertical column pipe
Pump type Required pedestal height (A)
[mm]
Range 72
S2.90.250.xxxx.x.x 375
S2.100.250.xxxx.x.x 375
S2.100.300.xxxx.x.x 400
S3.110.300.xxxx.x.x 400
S3.120.500.xxxx.x.x 425
S3.135.500.xxxx.x.x 425
S3.140.600.xxxx.x.x 425
Range 74
S2.90.xx.xxx.xxxx.x.x 400
S2.100.xxx.xxx.xxxx.x.x 400
S3.110.xxx.xxx.xxxx.x.x 400
S3.120.xxx.xxx.xxxx.x.x 425
S3.135.xxx.xxx.xxxx.x.x 425
Range 78
Pressure class E, L, M, H 425
Pressure class F 0
TM03 3067 0208
Required tilt
angle when
pump is lowered
on auto coupling:
5 ° ± 5 °
TM03 1629 0208TM03 1498 4809TM04 6899 1110

English (GB)
12
6.2 Start and stop levels
The start and stop levels are specified during the design stage.
Always check that the start/stop levels function and possibly alter
them when commissioning the pump in order to ensure good
operation.
The stop level should be as low as possible, so that the flow
velocity in the pit increases towards the end of the working cycle.
In pumping stations with several different stop levels, such as in
frequency-controlled installations, it is important to program the
control sequence to pump down to the lowest stop level at least
once per day to clean out the bottom. Limits for the stop level are
set by the motor submergence required to ensure cooling, by the
onset of pump cavitation or by the level where air is sucked into
the pump inlet. The lowest level cannot always be foreseen, but
must be confirmed through trials during pumping station
commissioning.
Further details regarding stop and start levels for submerged or
dry installation appear under sections 6.3 Submerged installation
on auto-coupling and 6.5 Dry installation.
6.3 Submerged installation on auto-coupling
Pumps for permanent installation can be installed on a stationary
auto-coupling and operated completely or partially submerged in
the pumped liquid.
Before installing the auto-coupling base unit ensure the quality
and strength of the concrete foundation. Table A below shows the
pull-out strength required for expansion bolts of the auto-
coupling. To ensure adequate pull-out strength we recommend
that you weld the threaded bushings to the steel reinforcement in
the concrete.
1. Drill mounting holes for the guide rail bracket on the inside of
the pit and fasten the guide rail bracket provisionally with two
screws.
2. Place the auto-coupling base unit on the bottom of the pit.
Use a plumb line to establish the correct positioning.
Fasten the auto-coupling with expansion bolts. If the bottom of
the pit is uneven, the auto-coupling base unit must be
supported so that it is level when being fastened.
3. Assemble the discharge pipe in accordance with the generally
accepted procedures and without exposing the pipe to
distortion or tension. No loads from the pipework weight must
be carried by the auto-coupling.
4. Fit the guide rails. An intermediate guide rail bracket is
required if guide rails are more than 6 m long. Place the guide
rails on the auto coupling, then place the guide rail bracket on
the guide rails and fasten the guide rail bracket to the wall.
Tighten the expansion bolts.
5. Clean out debris from the pit before lowering the pump into
the pit.
6. Before lowering the pump into the wet pit, check the cables
visually for cuts or ruptures which may have been caused by
rough handling during transportation or installation.
7. Slide the guide claw of the pump between the guide rails and
lower the pump into the pit by means of a certified chain
secured to the lifting bracket of the pump. When the pump
reaches the auto-coupling base unit, the pump will
automatically connect tightly.
8. Hang up the end of the chain on a suitable hook at the top of
the pit and in such a way that the chain cannot come into
contact with the pump.
9. Adjust the length of the motor cables but remember to have
enough cable length to be able to make service on the pump.
Make sure that the cables are not sharply bent or pinched.
Fix the cables at the top of the pit in such a way that no extra
cable slides into the pit.
10. Connect the motor cables and the sensor cable.
Table A
Please note that the strengths given are without safety factor.
Required safety factor may depend on the materials and the
method used for anchoring.
6.4 Column pipe installation
Pumps for column pipe installation are installed permanently in a
column pipe. Grundfos does not normally supply the column pipe.
Dimensioning of the column pipes is suggested in the pump
specific dimensional drawings.
1. Fit the seat ring to the bottom of the column pipe.
2. Clean out debris from the pit.
3. Before lowering the pump into the column pipe, check the
cables visually for cuts or ruptures which may have been
caused by rough handling during transportation or installation.
4. Lower the pump into the column pipe by means of a certified
chain secured to the lifting bracket of the pump. The pump will
sit against the conical surface of the seat ring. Normally the
friction between the conical surfaces will prevent the pump
from rotating. As an extra precaution there are three guide
pins on the seat ring which will limit the possible rotation to
maximum 60 °.
5. Hang up the end of the chain above or at the top of the
column pipe in such a way that the chain cannot come into
contact with the pump.
6. Adjust the length of the cables but remember to have enough
cable length to be able to service the pump. Make sure that
the cables are not sharply bent or pinched. Fix the cables in
such a way that there is no extra slack in the column pipe.
With long columns it may be necessary to arrange cable
support for the cable inside the column pipe. If necessary,
please contact Grundfos.
7. Connect the motor cables and the sensor cable.
Fig. 21 Column pipe installation pump type ST
Note
For auto-coupling installations (types S and C),
the guide claw is mounted on the discharge
flange from factory.
Caution
Avoid pipe tension at flanges and bolts.
Caution
The free end of the cables must not be
submerged, as water may penetrate through the
cables into the motor.
Auto-coupling
base unit Expansion bolts Pull-out strength
[kN]
DN 250 4 x M24 25
DN 300 4 x M24 40
DN 500 6 x M30 40
DN 600 6 x M30 40
DN 800 6 x M30 25
TM04 6908 1110
72 and 74: 900 mm
78: 1100 mm
All: 400 mm

English (GB)
13
6.5 Dry installation
Pumps in dry installation are installed permanently in a pump
room.
The pump motor is enclosed and watertight and will not be
damaged if the installation site is flooded with water.
1. Mark and drill mounting holes in the concrete foundation.
2. Fit the base stand on the concrete with expansion bolts.
3. Check that the base stand is horizontal.
4. Fasten the pump to the base stand.
In order to facilitate service on the pump, we recommend that you
fit isolating valves on either side of the pump.
5. Fit the suction and discharge pipes and isolating valves, if
used, and ensure that the pump is not stressed by the
pipework.
6. Adjust the length of the motor cables but remember to have
enough cable length to be able to service the pump.
Make sure that the cables are not sharply bent or pinched.
7. Connect the motor cables and the sensor cables according
the wiring diagrams.
The suction and discharge pipes are bolted to the pump by
means of flange connections.
Stop levels
The stop level setting for dry-installed pumps depends on the
suction pipe inlet height, shape and flow velocity. Set the stop
level approx. one inlet pipe diameter above the suction pipe inlet.
The final stop level should be confirmed through test runs during
pumping station commission.
Start levels
In pumping stations with dry-installed pumps, set the starting
levels above the pump housing in order to ensure that the cooling
jacket is filled up before the pump starts pumping. For vertical
pumps, this height may be considerable and should be set with a
margin according to fig. 22.
Fig. 22 Vertical, dry installation (D)
Horizontal pumps do not normally require special considerations
for the start levels, if the suction pipe is designed to prevent air
pockets from forming, see fig. 23.
Fig. 23 Horizontal, dry installation (H)
Legend to figures 23 and 24:
Sis the minimum stop level. The minimum distance S above the
suction pipe is required to avoid the formation of vortices at the
suction pipe and thus to avoid air getting sucked into the pump.
Air in the pumped liquid may cause vibrations, cavitation and loss
of pump performance.
Gis the minimum start level of a dry-installed, vertical pump if no
other actions are taken to ensure that the pump housing is filled
with pumped liquid when the pump is started. Other actions could
be to use a vacuum pump to suck liquid into the pump housing
(requires isolating valve on the pressure side) or (after the first
startup) a non-return valve in the discharge pipe which prevents
the draining of the pump housing between running periods.
Note
For vertical, dry installations, type D, the pump
needs to be installed on a permanent concrete
foundation.
Note
For horizontal, dry installations, type H, the pump
is mounted on a base stand from factory.
Note
We recommend that you use a reducer between
the suction pipe and the pump in dry
installations. In horizontal installations the
reducer must be of the eccentric type and must
be installed so that the straight edge is pointing
upwards. In this way, the accumulation of air in
the suction pipe is avoided and the risk of
disturbance of operation is eliminated.
See fig. 23.
Note
Make sure that the pipework is installed without
the use of undue force. No loads from the
pipework weight must be carried by the pump.
We recommend that you use loose flanges to
ease the installation and to avoid pipe tension at
flanges and bolts.
Note
Do not use elastic elements or bellows in the
pipework; these elements should never be used
as a means to align the pipework.
TM05 8187 2013TM04 6901 1110
Minimum stop level S = D1
Minimum distance between bottom of pit
and lowest part of suction pipe F = 0.5 x D1
Minimum start level G = Dp
G
S
D
F
Dp
1
Reduction
elbow
Eccentric reducer

English (GB)
14
7. Motor protection
Motor protection devices
The motors have three thermal protectors connected in series
and two moisture switches connected in series. Protectors and
switches are connected in two separate circuits. The thermal
protectors are of the reversible type, and the moisture switches
are of the irreversible type. The thermal protection circuit
(conductors 1 and 3) and the moisture protection circuit
(conductors 2 and 3) have separate outputs to enable separate
alarms if motor is overheated or affected by moisture.
All other sensor connections are either led out of the motor
(sensor version D) via conductors 4 to 9, see fig. 26, or
connected to the sensor board (sensor version B) and led out of
the motor via conductors 4 and 5.
7.1 IO 113
IO 113 forms interface between a Grundfos sewage and
wastewater pump with analog and digital sensors and the pump
controller. The most important sensor data are indicated on the
front panel.
One pump can be connected to an IO 113 module.
Together with the sensors, IO 113 forms a galvanic separation
between the motor voltage in the pump and the controller
connected.
IO 113 can do the following as standard:
• Protect the pump against overheating.
• Monitor the status of these items:
- motor winding temperature
- leakage (WIO)
- moisture in pump.
• Measure the stator insulations resistance.
See section 7.1.2 Measurement of insulation resistance.
• Stop the pump in case of alarm.
• Remotely monitor the pump via RS-485 communication
(Modbus or GENIbus).
• Control pump via a frequency converter.
When IO 113 is combined with SM 113, it is also possible to
monitor the bearing temperature and rotor speed when the motor
is switched off.
7.1.1 Galvanic separation
Double-insulated sensors for all measurements ensure the
electrical safety. Furthermore, there is a galvanic separation
inside IO 113.
7.1.2 Measurement of insulation resistance
IO 113 measures the insulation resistance between a stator
winding and earth:
• Resistance above 10 MΩ= ok.
• Resistance between 10 MΩand 1 MΩ= warning.
• Resistance below 1 MΩ= alarm.
7.2 SM 113
SM 113 is designed and used for the collection and transfer of
additional sensor data. SM 113 works together with IO 113 (with
communication module, product number 98097390) as shown in
the figure below.
Fig. 24 IO 113 and SM 113
SM 113 can collect data from these devices:
• Current sensors, 4-20 mA*
• Pt100**/ Pt1000*** thermal sensors.
* Vibration sensor, water-in-oil or water-in-air sensor
(WIO or WIA)
** Maximum three Pt100 sensors
*** Maximum four Pt1000 sensors
7.3 Switches and sensors
A pump includes the following switches and sensors:
• three thermal switches in the stator windings
• thermal protectors
• a moisture switch in the top cover
• a moisture switch in the stator housing
• a Pt100 in the stator winding (analog)
• a Pt100 in the upper bearing (analog)
• a Pt100 in the lower bearing (analog)
• a WIO (water-in-oil) sensor in the oil chamber (analog).
Fig. 25 Sensor cable seen towards the pump
TM05 1966 4111 - TM03 4083 1606
Warning
Dry-running is not allowed!
Install an additional level switch to ensure that
the pump is stopped in case the primary stop
level switch is not operating.
TM03 2802 4805
PET1 T2 G1 A1 G2 A2 K1 K2 R1 R2
D1 D2 D3 D4 D5 D6 D7 D8
P1 P2 P3 P4 P5
AYB
I1 I2 I3
ON DIP
12345678910
11 12
1234567891011121314
Power line
communication
using Grundfos
GENIbus protocol
IO 113 SM 113
Sensor inputs
12
3
4
5
6
7
8
9
Yellow/green

English (GB)
15
Fig. 26 Sensor connections, SM 113 outside motor
7.3.1 Thermal switches
The thermal protection against overheating is achieved with
bimetallic switches as standard or thermistors as optional.
The three thermal switches that are hardwired from the pump to
the IO 113 unit (or similar controller) will open if the stator
windings become too hot. The thermal switches are of the
reversible type and will close again when the motor has cooled
down.
This generates both a hardware and software alarm in the IO 113,
and the alarm relay will open.
7.3.2 Pt100
S pumps, ranges 72, 74 and 78 are equipped with Pt100 sensors
in the stator windings, in the upper bearing bracket and in the
lower bearing bracket.
Pt100 makes an analog measurement from 0-180 °C.
The value is measured by the SM 113 and transferred to the
IO 113 through serial communication.
7.3.3 WIO (water-in-oil) sensor
The oil chamber is filled with oil acting as lubricant and coolant for
both mechanical seals.
The WIO sensor measures the water content in the oil chamber:
• 0-20 % water in the oil = no reaction
• water content outside measuring range = warning
• oil level too low = alarm.
Technical data
The sensor is approved as CE 0344 II 2 GD Ex mb II T4,II 2 D
Ex mD 21 T135 °C IP68 according to EN 60079-0:2006,
EN 60079-18:2004, EN 61241-0:2006 and EN 61241-18:2004.
7.3.4 Moisture switch
The pump has two moisture switches, one in the top cover and
one in the stator housing. The moisture switches are of the
irreversible type and must be replaced if activated.
The moisture switches are hardwired from the pump to the IO 113
(or similar controller). They will open if moisture is detected and
thus break an electric circuit.
This will generate both a hardware and software alarm in the
IO 113, and the alarm relay will open.
TM04 6067 4809
Warning
The installer/user must install an automatic
circuit breaker, e.g. IO 113, which disconnects the
power supply in case the thermal switches or the
moisture switches are not operating.
IO 113 must not be installed in potentially
explosive environments.
IO 113 SM 113
S
Analog and digital
outputs
PL3
L2
L1
Power
side
Signal
side
WIO sensor
"mb" approval
"d" enclosure
Symbol Description
T Thermal switch
M Moisture switch
S Sensor input
SM 113 Sensor board
IO 113 IO 113 with internal alarm
relay (250 VAC)
"d" Flameproof enclosure
Note: Range 72 only
"mb" Protection according to
EN/IEC 60079-18:2004
Pump range
Alarm temperatures
Winding
temperature
[°C]
Upper
bearing
[°C]
Lower
bearing
[°C]
72 150 120 100
74 150 120 120
78 150 120 120
Warning
In case of overheating caused by wear, lack of
lubricant etc., the Pt100 sensors will trip an alarm
and cut off the power supply at a preset
temperature.
Maximum acceptable alarm temperature can be
seen in the table above.
Warning
Lack of oil may cause overheating and damage of
the mechanical seals. The WIO sensor in the oil
chamber will trip the alarm if the oil quality is
poor or there is not enough oil in the oil chamber.
Input voltage: 12-24 VDC
Output current: 3.4 - 22 mA
Power input: 0.6 W
Ambient temperature: 0-70 °C

English (GB)
16
8. Electrical connection
The supply voltage and frequency are marked on the pump
nameplate. Make sure that the motor is suitable for the power
supply available at the installation site.
The pump must be connected to a motor-protective circuit
breaker.
In the case the pump does not have an SM 113, the Pt100
sensors must be hard-wired out of the pump, see fig. 26, and
connected to an external unit.
In the case the pump has an SM 113, the Pt100 sensors must be
connected to the SM 113. No external unit is required.
The motor is effectively earthed via the earth conductors of the
power cables and the pipework. The motor top cover for Ex
pumps is equipped with connections for external earthing or an
equipotential bonding conductor.
The most commonly used startup methods are direct-on-line
starting (DOL), star-delta starting (Y/D) and soft start. The pump
can even be started via a frequency converter according to the
frequency converter manufacturer's specifications. The selection
of suitable starting method depends on several considerations on
usage and mains supply conditions.
Fig. 27 Direct-on-line starting
Fig. 28 Star-delta starting
8.1 Cross-sections for power cables
There are three different types of power cable in use:
• one standard four-core power cable
• two different types of EMC power cable.
All cable types are shown in this booklet.
8.1.1 Standard power cable
Fig. 29 Standard power cable
Warning
Connect the pump to an external mains switch
ensuring all-pole disconnection with a contact
separation according to EN 60204-1, 5.3.2.
It must be possible to lock the mains switch in
position 0. Type and requirements as specified in
EN 60204-1, 5.3.2.
The electrical connection must be carried out in
accordance with local regulations.
Warning
The pumps must be connected to a control box
with a motor protection relay with an IEC trip
class 10 or 15.
Warning
Pumps installed in hazardous locations must be
connected to a control box with a motor
protection relay with an IEC trip class 10.
Component Voltage Tolerance
Motor See pump nameplate ± 10 %
Thermal switches Max. 240 V ± 10 %
Thermistors 2.5 - 7.5 V -
Moisture switches Max. 240 V -
Other sensors Max. 14 VDC ± 1 V
SM 113 Max. 14 VDC ± 1 V
Warning
For Ex models in dry installation (version D and
H), we recommend that you also connect an
external earthing.
Warning
Before installation and the first startup of the
pump, check the condition of the cables visually
to avoid short circuits.
Note
When using star-delta starting, it is important to
keep switching transient time to a minimum to
avoid high transient torques. We recommend that
you use a time relay with a switching time of
maximum 50 ms or according to the starter
manufacturer's specifications.
TM05 1638 3311TM05 1639 3311TM05 5943 4212
V1 W1U1 PE
V2U2W2
PEL1
M
L3L2
3
V1 W1U1 PE
V2U2W2
PEL1
M
L3L2
3
V1
U1W1
V2
U2W2
V1
U1
W1
V2
U2
W2
V1
U1
W1
V2
U2
W2
1
2
3
4
5
6
V1
U1
W1
V2
U2
W2

English (GB)
17
8.1.2 EMC power cables
Fig. 30 Screened EMC cable (ground)
Fig. 31 EMC cable with separate protective earth conductors
8.2 Wiring diagram for sensors
Fig. 32 Wiring diagram for sensors
8.3 Frequency converter operation
In principle, all three-phase motors can be connected to a
frequency converter.
However, frequency converter operation will often expose the
motor insulation system to a heavier load and cause the motor to
be more noisy than usual due to eddy currents caused by voltage
peaks.
In addition, large motors driven via a frequency converter will be
loaded by bearing currents.
For frequency converter operation, please observe the following
information:
• Requirements must be fulfilled.
• Recommendations ought to be fulfilled.
• Consequences should be considered.
TM05 5944 4212
V1
U1
W1
V2
U2
W2
V1
U1
W1
V2
U2
W2
1
2
3
4
5
6
V1
U1
W1
V2
U2
W2
V1
U1
W1
V2
U2
W2
TM05 5945 4212
V1
V1
U1
W1
V2
U2
W2
V1
U1
W1
V2
U2
W2
U1
U2
V1
V2
W1
W2
V1
U1
W1
V2
U2
W2
U1
W1
V2
U2
W2
TM05 5947 4212
Note
Wiring diagrams in the custom-built products may be different from the standard. In this case we recommend that
you contact the nearest Grundfos company or authorized workshop.
Terminal board connection
Oil indicator
4...20 mA
Pt100 in upper bearing
Pt100 in stator
Pt100 in lower bearing
Thermal switches
Thermistors
Moisture switches
Warning
When motor is driven via frequency converter,
the temperature class of range 72 explosion-
proof pumps must be T3.

English (GB)
18
8.3.1 Requirements
• The thermal protection of the motor must be connected.
• Peak voltage and dU/dt must be in accordance with the table
below. The values stated are maximum values supplied to the
motor terminals. The cable influence has not been taken into
account. See the frequency converter data sheet regarding the
actual values and the cable influence on the peak voltage and
dU/dt.
• If the pump is an Ex-approved pump, check if the Ex certificate
of the specific pump allows the use of a frequency converter.
• Set the frequency converter U/f ratio according to the motor
data.
• Local regulations/standards must be fulfilled.
8.3.2 Recommendations
Before installing a frequency converter, calculate the lowest
allowable frequency in the installation in order to avoid zero flow.
• Do not reduce the motor speed to less than 60 % (30 Hz) of
rated speed.
• Keep the flow velocity above 1 m/sec.
• Let the pump run at rated speed at least once a day in order to
prevent sedimentation in the piping system.
• Do not exceed the frequency indicated on the nameplate.
In this case there is risk of motor overload.
• Keep the motor cable as short as possible. The peak voltage
will increase with the length of the motor cable. See data sheet
for the frequency converter used.
• Use input and output filters on the frequency converter.
See data sheet for the frequency converter used.
• Use screened motor cable if there is a risk that electrical noise
can disturb other electrical equipment. See data sheet for the
frequency converter used.
8.3.3 Consequences
When operating the pump via a frequency converter, please be
aware of these possible consequences:
• The locked-rotor torque will be lower. How much lower will
depend on the frequency converter type. See the installation
and operating instructions for the frequency converter used for
information on the locked-rotor torque available.
• The working condition of bearings and shaft seal may be
affected. The possible effect will depend on the application.
The actual effect cannot be predicted.
• The acoustic noise level may increase. See the installation
and operating instructions for the frequency converter used for
advice as to how to reduce the acoustic noise.
9. Startup
Proceed as follows:
1. Lock the mains switch in position 0.
2. Check the oil level in the oil chamber. See section 10.1 Oil
check and oil change.
3. Check whether the impeller can rotate freely.
4. Check whether the monitoring units, if used, are operating
satisfactorily.
5. Open the isolating valves, if fitted.
6. Pumps in installation types S and C: Ensure visually that
the pump is properly connected to the auto coupling.
7. Make sure that the pump is submerged in the liquid.
Pumps in installation types D and H: Make sure that there
is liquid in the pit and that the pump housing and cooling
jacket are filled with water. Open the air vent valve (pos. 17 in
fig. 1) before or during the startup until water comes out of the
valve. Then close the valve.
Pumps in installation type C: The air vent valve must always
be open, also during operation. Check the setting of the level
switches.
8. Start the pump, and check the pump operation for abnormal
noise or vibrations.
9. After startup, the actual pump duty point must be established
as accurately as possible so that it can be checked whether
the operating conditions are as desired.
The operation of the pump should always take place in
accordance with established routines with scheduled checks of
pump monitoring equipment and accessories (valves, etc.).
Make sure that the pump and equipment settings cannot be
changed by unauthorized persons.
9.1 Checking the direction of rotation
A label with an arrow on the pump housing indicates the correct
direction of rotation. Direction of rotation must be clockwise
when seen from the drive end.
For installation types S, C and ST pumps: Observe the movement
of the pump (jerk) when started. If the pump jerks counter-
clockwise, the direction of rotation is correct.
For installation types D and H pumps: Check the duty point.
Maximum repetitive peak
voltage
[V]
Maximum dU/dt UN400 V
[V/μsec.]
850 2000
Warning
Before manual starting or changeover to
automatic control, make sure that no persons are
working on or near the pump.
Warning
Before the first startup and after a long standstill
period, make sure that the pump has been filled
with pumped liquid.
In dry installations with cooling jacket the
cooling jacket must always be filled with pumped
liquid when operating. Ensure this by venting
before the first startup.
Caution
In case of abnormal noise or vibrations from the
pump or other pump or liquid supply failures,
stop the pump immediately. Do not attempt to
restart the pump until the cause of the fault has
been found and the fault corrected.
Caution
The pump may only be started for a few seconds
without being submerged for checking of
direction of rotation.

English (GB)
19
10. Maintenance and service
Before carrying out maintenance and service, make sure that the
pump has been thoroughly flushed with clean water. Rinse the
pump parts in water after dismantling.
Pumps running normal operation should be inspected once a
year.
The following points should be checked:
• Power consumption
•Oil level and oil condition
See section 10.1 Oil check and oil change.
•Cable entry
Make sure that the cable entry is waterproof, that the cables
are not sharply bent or pinched, and that the cable sheaths
have no visual defects.
•Impeller clearance
Check the impeller clearance. See section 10.2 Inspection and
adjustment of impeller clearance.
•Pump parts
Check the pump housing, etc. for possible wear.
Replace defective parts.
•Ball bearings
Check the shaft for noisy or heavy operation (turn the shaft by
hand). Replace defective bearings.
A general overhaul of the pump is usually required in case of
defective bearings or poor motor function. This work must be
carried out by an authorized service workshop.
10.1 Oil check and oil change
The oil chamber is filled with oil acting as lubricant and coolant for
both mechanical seals.
Low oil level may indicate that the upper mechanical shaft seal is
defective. Contact an authorized service workshop for further
overhaul of the pump and repair, if required.
The oil in the oil chamber can be changed with the pump in either
horizontal or upright position. We recommend that you carry out
the oil change with the pump in horizontal position, if possible,
because in that way it is much easier to drain all the used oil out
of the chamber.
Horizontal position
Proceed as follows:
1. Place the pump in such a position that inspection screw (A) is
pointing upwards.
Fig. 33 Pump with inspection screw (A) upwards
Warning
During maintenance and service, including
transportation to service workshop, always
support the pump by means of lifting chains or
place it in horizontal position to secure stability.
Warning
Before starting work on the pump, make sure that
the mains switch has been locked in position 0.
Make sure that the power supply cannot be
accidentally switched on.
All rotating parts must have stopped moving!
Warning
Maintenance and service must be carried out by
specially trained persons.
Warning
In case of repairs, always use original service
parts from the manufacturer as this ensures
correct dimensions of flame path gaps.
The bolts used in motor must be class A4-80 or
A2-80 according to EN/ISO 3506-1.
Warning
Defective bearings may reduce the Ex safety.
Warning
The maintenance and service work on explosion-
proof pumps must be carried out by Grundfos or
a service workshop authorized by Grundfos.
Note
Check the oil regularly to avoid damage and
breakdown of the pump.
Warning
Lack of oil may cause overheating and damage of
the mechanical seals. The WIO sensor in the oil
chamber will trip the alarm if the oil quality is
poor or there is not enough oil in the oil chamber.
Note
Use oil with viscosity grade SAE 10 W 30 or
SAE 10 W 40.
Range
Oil quantity
Installation type
S C and D ST
72 25 litres 18.5 litres 25 litres
74 - 20 litres 25 litres
78 - 80 litres 80 litres
TM03 1628 2705
Warning
When slackening the screw A of the oil chamber,
note that pressure may have built up in the
chamber. Do not remove the screw until the
pressure has been fully relieved!

English (GB)
20
2. Place a clean container under the pump to collect all the
drained-off oil. Remove screw B and observe the oil level.
3. Check the oil level and take an oil sample to inspect the
condition of the oil. The oil becomes greyish white like milk if it
contains water. In normal operation a small leakage through
the mechanical shaft seals is expected to happen, but if the
water content in the oil is high, this may be the result of a
defective shaft seal.
The oil should be changed if it contains water. Oil not
containing water can be reused.
4. If the oil needs to be changed, remove screw C and allow all
the oil to drain from the chamber into the container.
Emulsified oil must be changed and disposed of.
5. Replace the O-rings, refit screw C and tighten securely.
Fill the oil chamber with oil to the correct level. Refit screws A
and B and tighten securely.
Upright position
Proceed as follows:
1. Identify the screws A, B and C and their positions relative to
each other. See fig. 33.
Fig. 34 Correct oil level of upright pump
2. Proceed as above and use screw B again for indication of the
level of oil in the oil chamber. See fig. 34.
3. When the pump is upright, the oil has to be pumped out of the
oil chamber. Use a suction pump with a flexible suction hose
that can be inserted deep into the oil chamber.
4. Pump out the oil using all the screw holes in turns so as to
reach all sections of the interior of the oil chamber. Collect the
drained oil in a clean container.
5. Replace the O-rings, refit screw C and tighten securely.
Fill the oil chamber with oil to the correct level. Refit screws A
and B and tighten securely.
10.2 Inspection and adjustment of impeller clearance
The correct axial clearance is 1.3 mm ± 0.2. The clearance
should be reset if it is 2.0 mm or more. The method for resetting
the clearance is different for dry-installed pumps, installation
types D and H, and submersible pumps, installation types S, C
and ST. For dry-installed pumps there are two methods.
All methods are described here.
10.2.1 Submersible pumps, installation types S, C and ST
Submersible pumps have a separate, adjustable pump suction
cover which may be shaped as a suction bell. When the pump is
installed or withdrawn, locate the six fastening screws of the
suction cover and the three set screws.
Use a feeler gauge to check the clearance between the impeller
and the suction cover all around the perimeter of the suction
opening. See fig. 35.
If the clearance needs adjustment proceed as follows:
1. Slacken all fastening screws and set screws between suction
cover and pump housing.
2. Use a mallet to tap at the suction cover and close the
clearance.
3. Open the clearance to specified value by turning the three set
screws.
4. Check that the clearance is uniform around the perimeter of
the suction opening.
5. Tighten the fastening screws and check that the clearance is
still uniform.
6. Turn the impeller by hand and check at several points.
Fig. 35 Impeller clearance, installation types S, C and ST
10.2.2 Dry-installed pumps, installation types D and H
The impeller clearance can be inspected and set with the pump
installed on the pump stand and connected to the pipework.
In these pumps, the suction cover is located between pump
housing and outer connection flange at the suction side of the
pump.
Depending on the construction, there are two ways to set the
impeller clearance.
Note
Used oil must be disposed of in accordance with
local regulations.
TM04 6924 1210
B
Warning
Never work under a pump when it is hanging
from crane!
Note
Before adjusting the clearance, clean the gap
between impeller and suction cover.
TM03 3362 0506