Centrifugal pump Rexa MINI3-S series

wastewaterelectricsubmersible

Overview
The Wilo-Rexa MINI3-S is an efficient submersible sewage grinder pump in a non-clog design with a radial macerator (double shear effect) for house and site drainage for detached and semi-detached houses. The compact, lightweight construction and optimised hydraulics/macerator combination enable safe drainage of small pump sumps (soakaways, catchment shafts) while allowing the use of minimal pipework to reduce installation costs.

Key benefits

• Macerator with double shear effect ensures excellent clogging resistance
• Optimised hydraulics/macerator combination for a broad coverage of the delivery head with low power consumption suitable for domestic power connections
• Use of the smallest possible pipework reduces installation costs
• Low weight ensures easy handling and application in domestic area
• High-quality motor with double sealing for long service life
• Stainless-steel motor housing provides high corrosion resistance, even when motor is non-immersed

Operation and installation
Pumps are available in versions with built-in plug or with bare cable ends. Versions with an attached float switch start automatically depending on the fill level. The built-in plug (CEE 7/7 Schuko) enables simple connection to existing domestic sockets; no additional electrical installation is necessary for single-phase plug versions.

Product features

• Radial macerator with double shear effect
• Motor housing made of corrosion-resistant stainless steel, double sealing
• Optimised hydraulics/macerator combination
• Discharge connection DN 32/40
• Version with float switch available for level-dependent control

Equipment / Function

• Radial macerator with double shear effect
• Thermal motor monitoring with bimetallic sensor
• Single-phase AC motor with self-switching thermal motor monitoring
• Single-phase AC motor with separate capacitor switchgear
• Different versions available:
  • Version “P”: with plug
  • Version “A”: with float switch and plug
  • Version “O”: bare cable ends

Type key (examples / explanation)
Example: Rexa MINI3-S03/M008-523/A
Rexa = Product family: Submersible sewage pump
MINI3 = Series
S = Macerator
03 = Nominal diameter of discharge port: DN 32/40
M = Mains connection version: M = single-phase (1~), T = three-phase (3~)
008 = Value/10 = rated power P in kW (0.75 kW shown as 008 -> 0.75 kW)
- = Not Ex-rated
5 = Mains frequency: 5 = 50 Hz, 6 = 60 Hz
23 = Key for rated voltage
A = Additional electrical equipment: O = bare cable end, P = with plug, A = with float switch and plug

Technical data

• Mains connection: 1~230 V, 50 Hz or 3~400 V, 50 Hz
• Rated power (example variants): 0.75 kW
• Submerged operating mode: S1
• Non-immersed operating mode: S3 10%
• IP rating: IP68
• Insulation class: F
• Fluid temperature range: 3 to 40 °C (37 to 104 °F)
• Discharge port: DN 32/40
• Connection cable length (example in table): 10 m (some variants); optional up to 30 m for 1~ motor and up to 50 m for 3~ motor depending on configuration

Materials

• Hydraulics housing: EN-GJL-250 (ASTM A48 Class 35/40B)
• Impeller: EN-GJL-250 (ASTM A48 Class 35/40B)
• Macerator: 1.4528/59 HRC (AISI 440B+Co)
• Motor housing: 1.4301 (AISI 304)
• Seals: Pump side: SiC/SiC; Motor side: NBR; Static: NBR
• Shaft end: 1.4401 (AISI 316)

Construction / Description
Fully submersible grinder pump for stationary and portable wet installation in intermittent operation. Surface-cooled single-phase or three-phase motors with thermal motor monitoring. Oil-filled sealing chamber with two mechanical seals. Horizontal discharge port with flange and oval connection. Hydraulics housing and impeller made of grey cast iron; macerator made of hardened steel for blades. The pump is not intended for use in hazardous areas.

Scope of delivery

• Pump
• Installation and operating instructions

Accessories

• Connection cable with fixed cable lengths (1~ motor: up to max. 30 m; 3~ motor: up to max. 50 m)
• Suspension unit for wet installation
• Fixation accessories and chains

Caractéristiques / spécifications techniques

• Model / series: Rexa MINI3-S
• Discharge: DN 32/40
• Rated power (typical): 0.75 kW
• Mains: 1~230 V, 50 Hz or 3~400 V, 50 Hz
• Operating modes: S1 (submerged), S3 10% (non-immersed)
• IP68, Insulation class F
• Fluid temperature range: 3–40 °C
• Macerator: radial macerator with double shear effect (hard-wearing, stainless/hardened materials)
• Versions available: P = plug, A = float switch + plug, O = bare cable end