Wilo-EMU 6″


Multistage 6” submersible pump in tie rod version for vertical and horizontal installation


  • Process water supply from boreholes and rainwater storage tanks
  • Municipal water supply
  • Sprinkling and irrigation
  • Pressure boosting
  • Pumping of water in industrial applications and water control
  • Operation of fountains
  • Pumping of water without long-fibre and abrasive constituents

Type key

Example: Wilo-EMU NK 63-17 + NU 611-2/15
Hydraulics: NK 63-17
NK Hydraulics
6 Diameter of the hydraulic unit in inches [“]
3 Size
17 Number of hydraulic stages
Motor: NU 611-2/15
NU Submersible motor
611 Size (4… = 4″, 5…, 611 = 6″)
2 Number of poles
15 nominal power

Special features/product advantages

  • Corrosion-free and wear-resistant due to housing made of bronze and impellers made of Noryl
  • Integrated non-return valve
  • Pressure shroud in corrosion-free and hygienic stainless steel version with rubber bearings for reducing noise and vibration


  • Multistage submersible-motor pump with radial impellers
  • Hydraulics and motor freely configurable according to power requirements
  • Integrated non-return valve
  • NEMA coupling
  • Three-phase motor for direct or star-delta starting
  • Hermetically cast motors
  • Rewindable motors

Technical data

  • Minimum Efficiency Index (MEI) to ≥ 0.7
  • Mains connection: 3~400 V, 50 Hz
  • Submerged operating mode: S1
  • Max. fluid temperature: 30 °C, higher temperature upon request
  • Minimum flow rate at motor:
    • NU 4… = 0.1 m/s
    • NU 5… = 0.16 m/s
    • NU 6… = 0.1 ‐ 0.5 m/s
  • Max. sand content: 35 g/m3
  • Max. number of starts: 20/h
  • Max. submersion depth:
    • NU 4…, NU 5…= 350 m
    • NU 611 = 100 m
  • Protection class: IP 68
  • Control range for frequency converter: 30-50 Hz


Submersible-motor pump for vertical or horizontal installation.


Multistage submersible-motor pump with radial hydraulics. Housing parts made of NiAl‐Bz, impellers made of Noryl. Pressure connection as threaded connection, with integrated non-return valve.


Three-phase motor for direct and star-delta start Sealed, hermetically cast motor with enamel-insulated winding, resin-impregnated (NU 4…, NU 5…) or rewindable motor with PVC‐insulated winding (NU 611). Motor shroud made of stainless steel, A2/A4 quality.

Pump connection as standard NEMA connection. Sealing of motor shaft achieved through the use of a rotary shaft seal (NU 4…) or mechanical seal made of solid silicon carbide material.

Self-lubricating motor bearing. Motors in the NU 4…- and NU 5… series are filled with a water‐glycol mixture, motors in the NU 611 series are filled with a water-glycerine mixture. Alternatively, NU 611… series motors can be filled with drinking water (T‐version). Frequency converter operation is permitted (SF 1.1).


The motor is cooled by the fluid. The motor must always be operated in submerged state. The limit values for the max. fluid temperature and the minimum flow rate must not be exceeded. Vertical installation is possible optionally with or without cooling jacket. For horizontal installation, bearing brackets must be used for reinforcement of the unit. A cooling jacket may be used to improve the inlet flow.

Pressure shroud

The pressure shroud is used for direct installation of the unit in the pipe network. Standard models are without mounted non-return valves. The maximum inlet pressure is 10 bar.


  • No suction mode is possible with these units!
  • The unit must be fully immersed in water during operation.

Scope of delivery

  • Hydraulics + motor fully assembled
  • Connecting cable approved for drinking water, cable cross-section and length per standard design or per customer request
  • Installation and operating instructions


  • Special materials
  • 60 Hz version
  • PT100 sensor for thermal motor monitoring

General notes - ErP (ecological design-) directive

  • The benchmark for most efficient water pumps is MEI ≥ 0.70
  • The efficiency of a pump with a trimmed impeller is usually lower than that of a pump with the full impeller diameter. The trimming of the impeller will adapt the pump to a fixed duty point, leading to reduced energy consumption. The minimum efficiency index (MEI) is based on the full impeller diameter.
  • The operation of this water pump with variable duty points may be more efficient and economic when controlled, for example, by the use of a variable speed drive that matches the pump duty to the system.
  • Information on benchmark efficiency is available atwww.europump.org/efficiencycharts