OS20-Pro / OS40-Pro / OS70-Pro LCD Digital Overhead Stirrer

Precision LCD digital overhead stirrers engineered for demanding laboratory and pilot-scale mixing. Featuring brushless DC motors, constant speed regulation under changing viscosity, tool-free self-locking chucks, and advanced safety circuits.

Up to 70L Stirring Volume | Brushless DC Motor | Constant Speed Control | RS232 Interface

Key Features

Brushless DC Motor: High-efficiency, maintenance-free motor delivers smooth power, quiet operation, and extended service life.
Constant Speed Regulation: Microprocessor control maintains set speed automatically despite sample viscosity changes.
Smooth Start & Run: Gentle acceleration prevents liquid spatter, splashing, and sample overflow.
Tool-Free Self-Locking Chuck: Self-locking drill chuck enables quick and easy impeller installation without tools.
Vapor Protection: Silicone protective hood shields the drill chuck from corrosive vapors and chemical splatters.
Pass-Through Top Shaft: “Top-cross” shaft design allows impeller height adjustments without moving the stirrer head.
Multi-Parameter LCD Display: Real-time display of set and actual speed, timer (0-99h59min), and torque (torque display on OS70-Pro).
Comprehensive Safety: Built-in spillage, stall, and overload protection safety circuits ensure secure operation.

Applications

Widely utilized in chemical synthesis, pharmaceutical manufacturing, physical and chemical analysis, petrochemical industries, polymer dissolution, cosmetics formulation, and high-viscosity biological sample preparation.

Technical Specifications

Specification	OS20-Pro	OS40-Pro	OS70-Pro
Max. Stirring Quantity [H2O]	20 L	40 L	70 L
Speed Range	50 – 2200 rpm	50 – 2200 rpm	50 – 1100 rpm
Speed Display Accuracy	±3 rpm	±3 rpm	±10 rpm
Time Settings Range	0 – 99 h 59 min	0 – 99 h 59 min	0 – 99 h 59 min
Max. Torque	40 N·cm	60 N·cm	300 N·cm
Max. Viscosity	10,000 mPa·s	50,000 mPa·s	100,000 mPa·s
Motor Type	Brushless DC motor	Brushless DC motor	Brushless DC motor
Motor Input / Output Power	60 W / 50 W	120 W / 100 W	180 W / 160 W
Total Power	70 W	130 W	200 W
Chuck Clamp Range Diameter	0.5 – 10 mm	0.5 – 10 mm	0.5 – 10 mm
Speed Display	LCD	LCD	LCD
Torque Display	LCD	LCD	LCD
Overload Protection Display	LCD	LCD	LCD
Dimensions (W × H × D)	83 × 220 × 186 mm	83 × 220 × 186 mm	83 × 220 × 186 mm
Weight	2.8 kg	2.8 kg	3.2 kg
Voltage, Frequency	100-240 V, 50/60 Hz	100-240 V, 50/60 Hz	100-240 V, 50/60 Hz
Protection Class	IP21	IP21	IP21
Permissible Ambient Temp. & Humidity	5 – 40 °C, 80% RH	5 – 40 °C, 80% RH	5 – 40 °C, 80% RH
Data Interface	RS232	RS232	RS232

Stirring Tools & Impellers (316L Stainless Steel & PTFE)

Cat. No.	Impeller Type	Specifications & Material	Application
18900071	Propeller Stirrer	Shaft L: 40 cm, Stirrer Ø: 5 cm, Shaft Ø: 8 mm, 316L Stainless Steel	Standard stirring at medium and high speed
18900072	Straight Stirrer	Shaft L: 40 cm, Stirrer Ø: 6 cm, Shaft Ø: 8 mm, 316L Stainless Steel	Low viscosity media at medium and high speeds
18900073	Paddle Stirrer	Shaft L: 40 cm, Stirrer Ø: 6.8 cm, Shaft Ø: 8 mm, 316L Stainless Steel	Gentle mixing at low and medium speeds
18900074	Centrifugal Stirrer	Shaft L: 40 cm, Stirrer Ø: 9 cm, Shaft Ø: 8 mm, 316L Stainless Steel	Blades open while speeding; for narrow neck vessels
18900075	Propeller Stirrer (PTFE)	Shaft L: 35 cm, Stirrer Ø: 6.5 cm, Shaft Ø: 8 mm, PTFE Coated	Standard stirring with high chemical resistance
18900076	Straight Stirrer (PTFE)	Shaft L: 35 cm, Stirrer Ø: 7 cm, Shaft Ø: 8 mm, PTFE Coated	Low viscosity media with high chemical resistance
18900077	Paddle Stirrer (PTFE)	Shaft L: 35 cm, Stirrer Ø: 6.8 cm, Shaft Ø: 8 mm, PTFE Coated	Gentle mixing at low/medium speeds with acid/alkali resistance
18900078	Centrifugal Stirrer (PTFE)	Shaft L: 35 cm, Stirrer Ø: 8.5 cm, Shaft Ø: 8 mm, PTFE Coated	Blades open while speeding; for narrow neck glass vessels
18900478	Grand Propeller Stirrer	Shaft L: 60 cm, Stirrer Ø: 10 cm, Shaft Ø: 8 mm, 316L Stainless Steel	Standard stirring in large containers
18900499	Grand Paddle Stirrer	Shaft L: 60 cm, Stirrer Ø: 10 cm, Shaft Ø: 8 mm, 316L Stainless Steel	Gentle mixing for shear-sensitive fluids in large volumes
18900498	Grand Anchor Stirrer	Shaft L: 60 cm, Stirrer Ø: 10 cm, Shaft Ø: 8 mm, 316L Stainless Steel	High viscosity fluids or easily precipitating suspensions
18900500	Grand Dissolving Stirrer	Shaft L: 60 cm, Stirrer Ø: 10 cm, Shaft Ø: 8 mm, 316L Stainless Steel	Breaking down granules with strong shear force
18900625	Flat-Blade Stirrer	Shaft L: 40 cm, Stirrer Ø: 6 cm, Shaft Ø: 8 mm, 316L Stainless Steel	Low to medium viscosity materials at medium speed
18900627	Anchor Stirrer	Shaft L: 40 cm, Stirrer Ø: 6 cm, Shaft Ø: 8 mm, 316L Stainless Steel	Medium to high viscosity materials at low speed
18900626	Radial-Flow Stirrer	Shaft L: 40 cm, Stirrer Ø: 5 cm, Shaft Ø: 8 mm, 316L Stainless Steel	Gas-in-liquid dispersion and high speed agitation
18900628	Spiral Stirrer	Shaft L: 40 cm, Stirrer Ø: 5 cm, Shaft Ø: 8 mm, 316L Stainless Steel	Liquid homogenization and suspension treatment