OHAUS Explorer Plus Precision Microbalance EXP125ZH/AD

Overview

The OHAUS Explorer Plus Precision Microbalance EXP125ZH/AD is an ultra-micro analytical balance engineered for laboratories requiring trace-level mass measurement with uncompromising metrological integrity. Utilizing electromagnetic force compensation (EMFC) technology, the EXP125ZH/AD delivers high-resolution weighing at 0.01 mg readability across a 120 g maximum capacity—optimized for applications where microgram-level precision directly impacts method validity and regulatory compliance. Its design integrates ISO/IEC 17025-aligned metrological architecture with hardware-level safeguards including dual non-contact position sensors, active electrostatic neutralization via built-in ionizer, and auto-leveling mechanical foundation—ensuring consistent performance independent of minor surface irregularities or environmental charge accumulation. The balance meets the minimum weight requirements defined in USP (20 mg at 0.1% tolerance) and supports GLP/GMP workflows through full audit trail capability and secure user access control.

Key Features

• 7-inch detachable TFT color touchscreen with 16.7 million colors and capacitive glass interface—enabling glove-compatible operation and intuitive workflow navigation
• Fully automatic internal calibration with motorized mass deployment, triggered by time schedule, temperature drift, or manual command
• Auto-leveling system with integrated inclinometer and adaptive foot adjustment—eliminating manual bubble-level dependency
• Electrostatic mitigation suite: conductive zinc-alloy weighing pan, anti-static glass draft shield, and embedded ION-100A-class ionizer
• Enhanced draft shield with anti-pinch safety mechanism and optical proximity sensing—preventing accidental closure during sample handling
• Modular metal chassis with reinforced base and ESD-safe housing—designed for long-term stability in vibration-prone environments
• Real-time NTP time synchronization and HID-compliant USB interface—enabling direct plug-and-play connection to Windows/Linux hosts without driver installation

Sample Compatibility & Compliance

The EXP125ZH/AD accommodates diverse sample forms—including powders, crystalline solids, micro-vials, pipette tips, and density sinkers—within its 80 mm × 80 mm zinc-alloy pan. Its draft shield configuration complies with ISO 9001 and ISO/IEC 17025 environmental control recommendations for microbalance operation. The instrument supports regulatory data integrity standards including FDA 21 CFR Part 11 (with optional fingerprint scanner FIN-100A and LM842 wireless toolkit), EU Annex 11, and MHRA GxP guidance when configured with audit-trail-enabled software. Internal system logs retain up to 100,000 entries with timestamp, user ID, action type, and parameter change history—fully exportable via USB or Ethernet.

Software & Data Management

Embedded firmware enables 3000-entry sample library storage with customizable metadata fields (e.g., CAS number, batch ID, expiry date). All weighing events—including tare, net, differential, and density mode outputs—are timestamped and user-attributed. Data export supports CSV, XML, and PDF formats via USB host ports or TCP/IP network transfer. Optional connectivity modules (Wi-Fi, Bluetooth) allow integration into LIMS or ELN platforms using standard protocols (HTTP REST API, FTPS, or SMTP). Audit trail records include electronic signatures, session lockout after inactivity, and role-based permissions across four administrator tiers plus one guest level.

Applications

• Pharmaceutical R&D: Active pharmaceutical ingredient (API) quantification, reference standard preparation, and USP -compliant minimum weight verification
• Materials science: Nanoparticle mass characterization, catalyst loading validation, and thin-film deposition monitoring
• Clinical diagnostics: Trace reagent formulation, calibrator dilution series, and microfluidic device filling verification
• Quality control: Content uniformity testing (USP ), fill weight variance analysis, and syringe filter integrity checks
• Laboratory accreditation: ISO/IEC 17025 uncertainty budgeting, calibration certificate generation, and traceability documentation per ISO 17025:2017 clause 6.5
• Density determination: Dual-weighing mode with AV EP VP PA accessory kit for solid/liquid density per ASTM D792 and ISO 1183
• Pipette calibration: Gravimetric verification per ISO 8655-6 and CLSI EP15-A3 guidelines using EX-series pipette calibration kit

FAQ

What is the minimum weight requirement for this balance under USP ?
The EXP125ZH/AD achieves a minimum weight of 20 mg at 0.1% tolerance, satisfying USP criteria for ultra-micro applications.
Does the balance support 21 CFR Part 11 compliance out of the box?
Full Part 11 compliance requires optional accessories (FIN-100A fingerprint scanner, LM842 wireless module) and firmware configuration enabling electronic signatures, audit trails, and role-based access control.
Can the draft shield be operated manually if the auto-sensor fails?
Yes—the shield includes a mechanical override lever for manual opening/closing without interrupting balance operation or calibration status.
Is the internal calibration mass traceable to national standards?
The factory-installed calibration mass is certified to NIST-traceable standards with documented uncertainty and valid calibration certificate included with each unit.
How does the auto-leveling system function during routine use?
The system continuously monitors inclination via MEMS accelerometer and adjusts leveling feet electromechanically within ±0.2°—no user intervention required unless displacement exceeds 5 mm.