METTLER TOLEDO ML-T Precision Balance

Overview

The METTLER TOLEDO ML-T Precision Balance is an entry-level yet rigorously engineered analytical-grade instrument designed for laboratories requiring reliable, repeatable mass measurements in routine quality control, formulation, and educational applications. Built upon METTLER TOLEDO’s proprietary MonoBloc weighing technology, the ML-T employs a single-piece electromagnetic force compensation sensor that eliminates mechanical hysteresis and ensures long-term stability across varying environmental conditions. Its fully automatic internal calibration system—FACT (Fully Automatic Calibration Technology)—integrates a temperature-compensated reference mass and triggers recalibration whenever ambient temperature drifts beyond ±1.5 °C, guaranteeing consistent accuracy without manual intervention. With a capacity of up to 6200 g (model-dependent) and readability of 0.001 g, the ML-T meets the performance criteria defined in ISO 8655-6 for precision balances and supports minimum weight determination per USP and EUR Pharm 2.1.7 guidelines.

Key Features

• MonoBloc Single-Module Sensor: Monolithic electromagnetic force compensation design delivers high reproducibility and resistance to mechanical shock, vibration, and thermal gradients.
• FACT Internal Calibration: Temperature-sensitive auto-calibration ensures metrological integrity under dynamic lab conditions; no external weights required for routine verification.
• LevelControl Guidance System: Integrated inclinometer provides real-time visual feedback on touchscreen to assist rapid, precise leveling—critical for measurement fidelity at milligram resolution.
• QuickLock Draft Shield Mechanism: Tool-free, one-touch locking/unlocking of the glass draft shield enables fast access and hygienic cleaning without disassembly or misalignment risk.
• Compact Footprint & Robust Construction: ABS/PC composite top housing and die-cast metal base provide structural rigidity while minimizing space requirements on crowded benchtops.
• Battery Operation Support: Optional rechargeable battery module enables portable use in field labs, cleanrooms, or mobile QC stations where mains power is unavailable or restricted.

Sample Compatibility & Compliance

The ML-T accommodates a broad range of sample types—from powders and granules to small solid components—within its large pan diameter (≥160 mm) and generous under-pan clearance. Its draft shield configuration complies with ISO 9001 and ISO/IEC 17025 requirements for environmental isolation during sensitive weighing. All operational events—including calibration, leveling, zeroing, and parameter changes—are logged in the built-in SO (Service Operations) log with timestamps and operator ID (when password-protected user accounts are enabled). Up to four customizable sample IDs can be assigned per weighing session to prevent mix-ups and ensure full traceability in regulated environments. The balance supports GLP/GMP documentation workflows when paired with METTLER TOLEDO LabX Lite or full LabX software, enabling electronic signatures, audit trails, and 21 CFR Part 11 compliance.

Software & Data Management

Data transfer is streamlined via PC Direct mode: connecting the ML-T to a Windows or macOS computer via USB automatically mounts it as a virtual COM port, allowing direct entry of weight values into Excel, LIMS, or ELN systems without installing drivers or third-party software. For advanced integration, optional Bluetooth connectivity enables wireless transmission to tablets or networked workstations. The 4.5-inch color TFT touchscreen features intuitive icon-based navigation, multilingual UI (English, German, French, Spanish, Chinese, Japanese), and configurable data fields including tare, net/gross, % deviation, and statistical summaries (n, mean, SD, CV%). All statistics are calculated in real time and exportable via USB stick in CSV or PDF format.

Applications

• Routine QC testing in pharmaceutical manufacturing (e.g., active ingredient dispensing, tablet weight variation per USP )
• Raw material receipt inspection and batch release in chemical and food production facilities
• Student laboratory exercises in chemistry, biology, and materials science curricula
• Formulation development where repeatability at sub-milligram levels is essential but full analytical balance specifications are not mandated
• Inventory management and component counting in electronics assembly and medical device packaging lines

FAQ

What is the minimum weight (MinWeigh) function, and how does it support regulatory compliance?
The MinWeigh warning alerts users when a sample mass falls below the balance’s validated minimum weighable amount—calculated based on repeatability (sd) and required uncertainty. This enforces adherence to USP , EUR Pharm 2.1.7, and ISO 14412, preventing out-of-spec results due to insufficient signal-to-noise ratio.
Does the ML-T support external calibration with certified weights?
Yes—the balance accepts external calibration using Class M1 or better weights via the CAL key sequence; however, FACT internal calibration remains the recommended method for daily verification per manufacturer guidelines and ISO/IEC 17025 clause 6.5.2.
Can multiple users be assigned distinct access levels?
Password protection restricts access to calibration, leveling, and configuration menus. While the ML-T itself does not support multi-tier role-based permissions, integration with LabX software enables full user management, electronic signatures, and audit trail generation compliant with FDA 21 CFR Part 11.
Is the draft shield removable for cleaning?
The QuickLock mechanism allows full removal of the glass shield without tools; reinstallation maintains optical alignment and aerodynamic integrity—no recalibration is required after reassembly.
How is overload protection implemented in the MonoBloc sensor?
The MonoBloc architecture incorporates mechanical stop limits and electromagnetic saturation detection. When overload exceeds 150% of maximum capacity, the system halts excitation current and displays an “OVERLOAD” error, preventing sensor damage and preserving long-term linearity.