Wilo-Drain STS 40

Series description

Your advantages

  • Attached float switch (A-model) enables easy operation
  • Integrated pump support foot for easy installation
  • Impeller made of stainless steel
  • Lightweight


Submersible sewage pump for intermittent operation for stationary and portable wet well installation.


Pumping of

  • Sewage not containing faeces
  • Wastewater


  • Ready-to-plug single-phase version
  • A-model including float switch
  • Thermal motor monitoring

Scope of delivery

  • Pump ready for connection with 10 m connection cable
    • For 1~230 V with shockproof plug
    • For 3~400 V with bare cable end
  • ‘A version’ with attached float switch
  • Installation and operating instructions

Type key


Wilo-Drain STS 40/10-A


Submersible pump


Nominal diameter [mm]


Max. delivery head [m]


With float switch

Technical data

  • Mains connection: 1~ 230 V, 50 Hz or 3~ 400 V, 50 Hz
  • Submerged operating mode: S1 or S3 25 %
  • Protection class: IP68
  • Insulation class: B
  • Thermal winding monitoring
  • Max. fluid temperature: 3 – 35 °C
  • Cable length: 10 m
  • Max. immersion depth: 7 m
  • Free ball passage: 40 mm


  • Pump housing: EN-GJL-250
  • Pedestal: Cast iron
  • Impeller: Stainless steel 1.4301
  • Shaft: Stainless steel 1.4404
  • Mechanical seal on pump side: Carbon/ceramic
  • Shaft seal on motor side: NBR
  • Static gasket: NBR
  • Motor housing: Stainless steel 1.4301


Submersible sewage pump as submersible monobloc unit for stationary and portable wet well installation.


The outlet on the pressure side is designed as vertical threaded connection Rp 1½. Vortex impeller are used as the impeller shapes.


Surface-cooled motors give off their heat directly to the surrounding fluid via the housing components and can be used in immersed state for permanent or intermittent periodic duty.

A sealing chamber protects the motor from fluid ingress. The filling fluid used is potentially biodegradable and environmentally safe.

The single-phase AC motors are equipped with shockproof plugs, and ‘A versions’ with float switches. The three-phase motors are equipped with bare cable ends.


Sealing on the fluid side is achieved by a bidirectional mechanical seal, while sealing on the motor side is achieved by a rotary shaft seal.

Duty chart

Wilo-Drain STS 40


REACH regulation

Edition 2019-10
Page format 209.9 x 296.7 mm
Number of pages 4

PDF (1 MB)


General overview 2020 International version

Edition 2020
Version number 1
Page format 209.9 x 297.0 mm
Number of pages 78

PDF (48 MB)


General overview 2019 International version

Article Number 2200591
Edition 2018
Version number 1
Page format 209.9 x 297.0 mm
Number of pages 74

PDF (42 MB)


Wilo-Drain STS 40

Article Number 2068717
Edition 2014-04
Version number 02
Page format 209.9 x 297.0 mm
Number of pages 146

PDF (3 MB)


PDF: Wilo-Drain STS 40


Page selection

Format selection

Optional information

You can enter any personal information that you want to be displayed in the header.