High-efficiency, clog-resistant submersible sewage pumps with a cutting system, designed for draining single- and two-family homes and basic infrastructure.

The Wilo-Rexa MINI3-S submersible grinder pump excels at domestic and site drainage. Its compact design and radial cutter—featuring a dual-cutting action—reliably empty small pump sumps, such as septic tanks or collection wells. Installation costs are effectively reduced by allowing the use of smaller-diameter piping. The high-quality motor features a dual-seal system and is easy to maintain. The stainless steel motor housing offers excellent corrosion resistance, even during non-submerged operation. The lightweight, single-phase pump comes with a built-in plug for simple installation: just plug it into an existing socket. Equipped with a float switch, the pump operates automatically based on the liquid level:

Features/Product Advantages

Excellent clog resistance thanks to the cutter with dual-cutting action
Optimized hydraulics and cutter combination offering a wide head range and very low power requirements for domestic connections
Lower overall installation costs due to the use of smaller-diameter piping
Lightweight design suitable for domestic use
High-quality motor with dual seals ensures a long service life
Stainless steel housing guarantees excellent corrosion resistance, even when the motor is not submerged

Eco-friendly attributes

High-efficiency design using specialized components to minimize weight
Optimized hydraulics improve operational reliability and reduce unscheduled maintenance

Construction

Fully submersible grinder pump for stationary and portable wet-well installation in intermittent operation.

Fluids

Pumping within residential areas:

Sewage containing faeces
Wastewater (containing small amounts of sand)

Sewage pumping in accordance with the EN 12050 standard

The pump complies with the requirements of EN 12050-1.

Equipment/Function

Radial cutter with dual shearing action
Motor thermal protection with bimetallic sensor
Single-phase AC motor with self-switching thermal protection
Single-phase AC motor with separate capacitor box
Different versions:
Version "P": with plug
Version "A": with float switch and plug
Version "O": bare cable ends

Model code

Technical data

Mains connection: 1~230 V, 50 Hz or 3~400 V, 50 Hz
Operating mode (immersed): S1
Operating mode (non-immersed): S3 10%
Protection class: IP68
Insulation class: F
Fluid temperature: 3 ... 40 °C (37 ... 104 °F)

Materials

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

Type

Rexa MINI3-S ... /M ... /P

Submersible pump equipped with a radial cutter featuring a dual-shearing effect. Horizontal discharge port with flange and oval connections. Hydraulic housing and impeller made of grey cast iron; cutter made of hardened blade steel. Surface-cooled single-phase (1~) motor equipped with automatic motor thermal protection. Oil-filled seal chamber with two mechanical seals. Motor housing made of stainless steel. Detachable power cable with capacitor box and plug (CEE 7/7). The pump must not be used in potentially explosive atmospheres.

Rexa MINI3-S ... /M ... /A

Submersible pump equipped with a radial cutter featuring a dual-shearing effect. Horizontal discharge port with flange and oval connections. Hydraulic housing and impeller made of grey cast iron; cutter made of hardened blade steel. Surface-cooled single-phase (1~) motor equipped with automatic motor thermal protection. Oil-filled seal chamber with two mechanical seals. Motor housing made of stainless steel. Detachable power cable with capacitor box, float switch, and plug (CEE 7/7). The pump must not be used in potentially explosive atmospheres.

Rexa MINI3-S ... /T ... /O

Submersible pump equipped with a radial cutter featuring a dual-shearing effect. Horizontal discharge port with flange and oval connections. Hydraulic housing and impeller made of grey cast iron; cutter made of hardened blade steel. Surface-cooled three-phase (3~) motor equipped with motor thermal protection. Oil-filled sealing chamber with two mechanical seals. Motor housing made of stainless steel. Detachable power cable with bare cable ends. The pump must not be used in potentially explosive atmospheres.

Scope of delivery

Pump
Installation and operating instructions

Accessories

Power cable, fixed length:
1~ motor: max. 30 m (98 ft).
3~ motor: max. 50 m (164 ft).
Suspension device for wet-well installation
Mounting accessories and chain