DLAB OS-T40-Plus / OS-T60-Plus LCD Digital Overhead Stirrer

Overview

The DLAB OS-T40-Plus and OS-T60-Plus are microprocessor-controlled digital overhead stirrers engineered for precision mixing, dispersion, and homogenization in research laboratories, quality control facilities, and pilot-scale production environments. These instruments operate on the principle of direct-drive mechanical agitation using a high-efficiency brushless DC motor coupled to a precision planetary gear train. Unlike magnetic stirrers, overhead stirrers deliver consistent torque transmission independent of vessel geometry or sample depth—making them ideal for viscous, heterogeneous, or large-volume samples where magnetic coupling fails. The OS-T40-Plus supports up to 30 L working volume with maximum torque output suitable for medium-viscosity fluids (e.g., polymer solutions, suspensions), while the OS-T60-Plus extends capability to 50 L and higher torque demands (e.g., slurries, pastes, cementitious systems). Both models maintain constant rotational speed across viscosity fluctuations via real-time closed-loop torque feedback, ensuring reproducible shear history—a critical requirement in reaction kinetics, formulation development, and regulatory-compliant process validation.

Key Features

• High-resolution LCD interface displaying real-time values for rotational speed (rpm), relative torque (%), elapsed/remaining timer, and optional external temperature (°C)
• Precise digital timer with adjustable range from 1 minute to 99 hours and 59 minutes—enabling unattended long-duration mixing protocols
• Integrated keypad lock function prevents accidental parameter changes during operation, supporting ISO/IEC 17025 and FDA 21 CFR Part 11 alignment when combined with audit-trail-capable software
• “Top-entry” impeller mounting design allows rapid interchange of stirring elements (e.g., anchor, paddle, turbine, propeller) without disassembling the drive unit or repositioning the vessel
• Forward/reverse rotation switching facilitates de-agglomeration of settled particles and improves suspension uniformity in thixotropic media
• Built-in audible alert system emits distinct buzzer tones upon timer completion or fault detection (e.g., motor stall, sensor disconnect, thermal overload)
• User-accessible calibration routines for torque sensitivity and external temperature input—traceable to NIST-traceable reference standards
• Internal switching power supply eliminates reliance on external transformers, reducing electromagnetic interference and improving electrical safety per IEC 61010-1

Sample Compatibility & Compliance

These stirrers accommodate standard laboratory glassware (e.g., beakers, jacketed reactors, stainless-steel vessels) with diameters ranging from 80 mm to 350 mm. Compatible impeller types include axial-flow propellers (for low-viscosity liquids), radial-flow turbines (for turbulent dispersion), and helical ribbons (for high-viscosity pastes). The OS-T series complies with major international safety and performance standards including IEC 61010-1 (Electrical Safety for Laboratory Equipment), CE marking requirements, and RoHS directives. When used with validated temperature sensors and logged operational parameters, the system supports GLP documentation workflows and satisfies data integrity expectations under Annex 11 and ALCOA+ principles.

Software & Data Management

While standalone operation requires no PC connection, both models support RS-232 serial communication for integration into centralized laboratory information management systems (LIMS) or SCADA platforms. Optional DLAB StirControl™ software enables remote parameter setting, real-time data streaming (speed, torque, temperature), and export of timestamped CSV logs—including event markers for start/stop, direction change, and alarm triggers. All stored data retain metadata (user ID, instrument ID, date/time stamp), facilitating traceability in regulated environments such as pharmaceutical manufacturing (ICH Q7, USP ) and food safety testing (ISO 17025).

Applications

• Chemical Synthesis: Controlled addition of reagents under inert atmosphere; emulsion polymerization; catalyst suspension maintenance
• Materials Science: Dispersion of nanomaterials (CNTs, graphene oxide) in solvents; rheological conditioning of ceramic slurries prior to casting
• Pharmaceutical Development: Uniform blending of active pharmaceutical ingredients (APIs) with excipients; preparation of colloidal gold nanoparticles; dissolution testing support
• Food & Beverage QA/QC: Homogenization of viscous matrices (mayonnaise, nut butters, fruit pulps); standardized sample prep for rheometry or particle size analysis
• Cosmetics Formulation: Emulsification of oil-in-water systems; viscosity stabilization of surfactant-based gels and creams
• Construction Materials Testing: Mixing of cement paste, grout, and soil-cement composites per ASTM C305 and EN 196-1 protocols

FAQ

What is the difference between OS-T40-Plus and OS-T60-Plus?
The OS-T40-Plus is rated for up to 30 L maximum working volume and optimized for medium-viscosity applications, whereas the OS-T60-Plus delivers higher torque output and accommodates up to 50 L—suited for dense slurries and non-Newtonian pastes.
Can I connect an external temperature probe?
Yes—both models feature a dedicated Pt100-compatible analog input port; users may connect certified Class A or B probes for real-time temperature monitoring synchronized with mixing parameters.
Is torque calibration performed in-house or by service engineers?
Torque calibration is user-executable via the front-panel menu using supplied reference weights or certified torque test fixtures—no field service required.
Does the device meet FDA 21 CFR Part 11 requirements?
The hardware supports Part 11 compliance when deployed with validated software (e.g., StirControl™ v3.2+) that implements electronic signatures, audit trails, and role-based access control.
What impeller shaft lengths are supported?
Standard shaft lengths range from 150 mm to 600 mm (custom lengths available); all are precision-balanced and compatible with ISO 262 metric threads (M14×1.5).