Wilo NR 4 Series User manual

Installation and Operating Instructions
NR 4-6-8 05.23.06
Subject to technical changes!
WILO – USA, LLC & WILO Canada Inc. • 2915 10th Ave • Calgary, Alberta CAN • Tel. [phone] • Fax [phone]
WILO – NR 4”- 6“- 8“ series
Stainless Submersibles

NR series 4-6-8 Stainless Submersibles
WILO – USA, LLC & WILO Canada Inc. • 2915 10th Ave • Calgary, Alberta CAN • Tel. [phone] • Fax [phone]
Contents:
1 General Information
1.1 Uses
1.2 Technical characteristics
2 Safety
3 Transport and interim storage
4 Product and accessory description
4.1 Description
4.2 Pump
4.3 Motor
4.4 Accessories
5 Assembly / Installation
5.1 Assembly
5.2 Hydraulic connection
5.3 Electrical connection
6 Operation
6.1 Controlling the direction of rotation:
6.2 Operation
7 Maintenance
8 Problems, Causes and Solutions

NR series 4-6-8 Stainless Submersibles
WILO – USA, LLC & WILO Canada Inc. • 2915 10th Ave • Calgary, Alberta CAN • Tel. [phone] • Fax [phone]
1 General Information
Installation and service by qualified personnel only!
1.1.Uses
Submersible pumps of the NR series are suitable for drawing groundwater from deep
wells, for industrial use and for supplying water.
1.2 Product data
1.2.1Rating plate NR 6 30- 3
Submersible motor pump     
Nominal pump diameter   
Min. bore-hole diameter = 4”/6"/8"   
Nominal volume flow Q (gpm) x 10 ____________________  
Number of stages 
1.2.2Technical characteristics
Temperature range: +37 °F (3°C) to +86 °F (30°C)
Max. Flow rate: 1320 [gpm]
Max. immersion depth: 1148 ft
Maximum permissible sand content 50 g/m3
Pressure pipe connection:2" to 6", depending on size of pump
Max. pump lift: 650 ft to 1300 ft, depending on size of pump
2 Safety
These instructions contain important information which must be followed when installing
and operating the pump. These operating instructions must therefore be read before
assembly and commissioning by the installer and the responsible operator. Both the
general safety instructions in the “Safety precautions” section and those in subsequent
sections indicated by danger symbols should be carefully observed.
2.1 Danger symbols used in these operating instructions
Safety precautions in these operating instructions which, if not followed, could cause
personal injury are indicated by the symbol:
,
when warning of electrical voltage with
The following symbol is used to indicate that by ignoring the relevant safety instructions,
damage could be caused to the pump/machinery and its functions:
ATTENTION!
2.2 Staff training
The personnel installing the pump must have the appropriate qualifications for this
work.

NR series 4-6-8 Stainless Submersibles
WILO – USA, LLC & WILO Canada Inc. • 2915 10th Ave • Calgary, Alberta CAN • Tel. [phone] • Fax [phone]
2.3 Risks incurred by failure to comply with the safety precautions
Failure to comply with the safety precautions could result in personal injury or damage
to the pump or installation. Failure to comply with the safety precautions could also
invalidate any claims for damages.
In particular, lack of care may lead to problems such as:
Failure of important pump or machinery functions,
Personal injury due to electrical, mechanical and bacteriological causes.
Damage to property.
2.4 Safety precautions for the operator
Existing regulations for the prevention of accidents must be followed.
Dangers caused by electrical energy are to be excluded. Directives issued by the local
electrical code and the local electricity supply companies are to be observed.
2.5 Safety information for inspection and assembly
The operator must ensure that all inspection and installation work is carried out by
authorised and qualified specialists who have carefully studied these instructions.
Work on the pump/machinery should only be carried out when the machine has been
brought to a standstill.
2.6 Unauthorized modification and manufacture of spare parts
Alterations to the pump or installation may only be carried out with the manufacturer's
consent. The use of original spare parts and accessories authorised by the
manufacturer will ensure safety. The use of any other parts may invalidate claims
invoking the liability of the manufacturer for any consequences.
2.7 Unauthorized operating methods
The operating safety of the pump or installation supplied can only be guaranteed if it is
used in accordance with paragraph 1 of the operating instructions. The limiting values
given in the catalogue or data sheet must neither be exceeded nor allowed to fall below
those specified.
3 Transport and interim storage
Upon delivery, please check that the device has survived the journey undamaged. If
you find any damage, the normal routine measures are to be initiated with the shipping
company.
ATTENTION! During transport and in storage the pump must be protected against
moisture, frost and mechanical damage. Store horizontally in shockproof
places.
4 Product and accessory description
4.1.Description (see fig. 1)
1 Pump Wilo-Sub 4"/6"/8" 9 Mains connection/power supply
2 Immerson electrode mass 10 Manometer
3 Low-water immerson electrode (off) 11 Pressure vessel/reservoir
4 Immerson electrode upper level (on) 12 Shut-off valve
5 Connecting extension cable 13 Non-return valve
6 Dynamic level (pump running) 14 Motor connecting cable
7 Static level (pump switched off) 15 Cable connection between pos. 14 and pos. 5
8 Switch box (with dry-run protection)

NR series 4-6-8 Stainless Submersibles
WILO – USA, LLC & WILO Canada Inc. • 2915 10th Ave • Calgary, Alberta CAN • Tel. [phone] • Fax [phone]
4.2.Pump
Multistage submersible pump with radial or semi-axial impellers, depending on size of
pump, for use in 4", 6" and 8" bore-holes.
with built-in check valve.
4.3.Motor
Consult motor manufacturer’s documentation for more information.
4.4.Accessories
Accessories must be ordered separately.
Switching/controlling equipment (motor protection + pump control) pressure switch
assembly sensor assembly pressure reducer float-/diaphragm valve check valve
shut-off valves manometer safety valve dry-run protection device immerson
electrodes float switch motor cable as assembly (incl. plug) or piece goods (without
plug) heat-shrink cable connections steel cable (stainless steel) diaphragm
pressure vessel cooling-shroud (stainless steel/PVC) plug sets for cable connection
etc.
5 Assembly / Installation
The pump can be operated either vertically or horizontally (for horizontal position only
with a cooling-shroud). However, in the case of horizontal installation the number of
stages is limited, depending on size of pump:
Type of pump Max. … stages
NR 6-12.. 22
NR 6-18.. 18
NR 6-24.. 15
NR 6-35.. 12
NR 6-45.. 8
NR 8-42.. 14
NR 8-80.. 12
NR 8-100.. 8
NR 10-170.. 6
NR 10-250.. 4

NR series 4-6-8 Stainless Submersibles
WILO – USA, LLC & WILO Canada Inc. • 2915 10th Ave • Calgary, Alberta CAN • Tel. [phone] • Fax [phone]
ATTENTION! The maximum flows must be respected. Beyond maximum there is
risk of damage to the motor.
Type of pump max. flow gpm
NR 6-12.. 70
NR 6-18.. 114
NR 6-24.. 154
NR 6-35.. 216
NR 6-45.. 348
NR 8-42.. 286
NR 8-80.. 506
NR 8-100.. 598
NR 10-170.. 1056
NR 10-250.. 1320
5.1 Assembly
The bore-holes or pump stations must be created/arranged in accordance with the
generally applicable technical rules.
Please ensure that the flow of water in the bore-hole or well is sufficient for the
capacity of the pump.
The pump is carefully lowered using a double-purchase pulley on the suspension
rope and tripod/crane, heavy pumps using a rope winch.
Ensure that the pump never runs dry and make sure that even in dry periods the
water level never falls below the pump’s check valve (uppermost position).
ATTENTION! In the case of installation in a deep well (well shaft diameter greater than
a bore-hole), a reservoir, horizontal installation or in a deep well, a
cooling-shroud (accessory) must be fitted to the unit to ensure the motor
is properly cooled (fig. 2, pos. A).
It must be ensured that the well shaft in the bore-hole has a constant internal
diameter to allow the pump to be lowered freely for the entire depth of the shaft.
Never raise or lower the pump by the electric cable.
The electrical connection and extension of the motor cable must take place before
the pump is lowered and be tested/measured to ensure they are working.
The final installation position must be guaranteed such that the pump sits at least 1
foot above the bottom of the bore-hole or well (fig. 1).
The rating plate must be affixed in the immediate vicinity of the well head to allow
access at all times to the unit’s technical data.
Before lowering (and while lowering in deep bore-holes) the insulation resistance of
the motor and cable must be measured several times (min. 2 M).
5.2 Hydraulic connections (see fig. 1)
Connections to steel threaded pipes: 2" or 2 ½" , 3", 4" , 5", 6" depending on size of
pump.
If flexible pipework is used, the pump must be held by a chain/steel cable. The two
steel loops on the pump head are to be used for this.

NR series 4-6-8 Stainless Submersibles
WILO – USA, LLC & WILO Canada Inc. • 2915 10th Ave • Calgary, Alberta CAN • Tel. [phone] • Fax [phone]
In the case of larger types (8" / 10"), the pump is only connected directly to the
pipework.
It is recommended that a check valve be fitted on the pressure side of the pump
(between the ascending pipe in the bore-hole and the above-ground pipe installation)
at the well head.
A manometer, pressure switch/gauge and a shut-off valve are to be installed at the
head of the bore-hole/well.
5.3 Electrical connection
Electrical work must be carried out by a qualified and licensed electrician in
strict compliance with local regulations.
The maximum cable length depends on the nominal motor current and the
permissible drop in voltage over the entire cable length. Consult motor
manufacturer’s documentation for more information.

NR series 4-6-8 Stainless Submersibles
WILO – USA, LLC & WILO Canada Inc. • 2915 10th Ave • Calgary, Alberta CAN • Tel. [phone] • Fax [phone]
ATTENTION! A faulty electrical connection will result in damage to the motor.
6. Operation
6.1 Controlling the direction of rotation:
To determine the correct direction of rotation for the pump, only the shutoff pressure at
the well head needs to be checked, taking into account that the correct motor direction
of rotation generates the greater pressure.
To rectify an incorrect direction of rotation swap any two phases in the switchbox or
motor protection switch. See motor manufacturer’s documentation for more
information.
6.2 Operation
ATTENTION! The pump must never run while dry, not even for brief periods.
ATTENTION! Please note that not respecting this information may lead to premature
motor failure and or reduced life expectancy!
7 Maintenance
Before carrying out any maintenance work, switch off the pump and ensure
that it cannot be switched on again by unauthorized people. Never carry out
work on a running pump.
No special maintenance is required during normal operation.
7.1 Spare parts
Please contact Wilo Customer Service directly for spare parts, standard replacements
or repairs to the hydraulic pump parts.

NR series 4-6-8 Stainless Submersibles
WILO – USA, LLC & WILO Canada Inc. • 2915 10th Ave • Calgary, Alberta CAN • Tel. [phone] • Fax [phone]

NR series 4-6-8 Stainless Submersibles
WILO – USA, LLC & WILO Canada Inc. • 2915 10th Ave • Calgary, Alberta CAN • Tel. [phone] • Fax [phone]
8 Problems, Causes and Solutions
Problems Causes Solutions
The motor does not
run Consult motor manufacturer’s documentation for trouble shooting tips.
No or insufficient
capacity a)Voltage too low
b)Suction filter blocked
c)Incorrect motor direction of rotation
d)Low-water protection or water level
in well too low
a)Check electrical power supply at
switchgear.
b)Lift pump out of bore-hole, clean suction
filter.
c) Swap any two phases in the switchgear.
d)Check water level in bore-hole/well; it must
be at least 8” (20” if 8’’ motor) above the
pump pressure-pipe connection (during
operation).
Pump switches on too
frequently a)Insufficient switching difference between on/off pressure in pressure
switch/gauge
b)Incorrect arrangement of immerson
electrodes.
c)Storage volume of diaphragm
pressure vessel too small or
prepressure setting too low
a)Increase difference between on and off
points
b)Increase gaps between immerson
electrodes and thus regulate switching
times.
c) Check switching pressure settings and
reset
Check vessel prepressure (no water in
vessel)
Provide additional pressure vessel or
install tank with greater nominal volume.
If the fault cannot be remedied, please contact WILO customer services.
Subject to technical alterations!

NR series 4-6-8 Stainless Submersibles
WILO – USA, LLC & WILO Canada Inc. • 2915 10th Ave • Calgary, Alberta CAN • Tel. [phone] • Fax [phone]
Fig. 1
Refer to clause 4.1

NR series 4-6-8 Stainless Submersibles
WILO – USA, LLC & WILO Canada Inc. • 2915 10th Ave • Calgary, Alberta CAN • Tel. [phone] • Fax [phone]
Fig. 2