OHAUS Navigator® NV622ZH Portable Precision Balance
| Brand | OHAUS |
|---|---|
| Origin | Jiangsu, China |
| Manufacturer Type | Manufacturer |
| Product Category | Domestic |
| Model | NV622ZH |
| Instrument Type | General-Purpose Portable Balance |
| Capacity Range | 200–500 g |
| Readability | 0.01 g |
| Repeatability | ±0.02 g |
| Maximum Overload Capacity | 400% of full scale (up to 2480 g) |
| Calibration | External |
| Protection Class | IP42 (dust and splash resistant) |
| Power Supply | AC adapter or 4 × AA batteries (optional) |
| Tare Range | Full capacity |
| Weighing Units | g, oz, ct, dwt, lb, ozt, GN, momme, tola, tael (HK/SG), tl (TH), kg |
Overview
The OHAUS Navigator® NV622ZH is a general-purpose portable precision balance engineered for reliability, speed, and operational consistency in non-regulated and light-duty regulated environments. Built on OHAUS’ proven load cell architecture, it employs electromagnetic force compensation (EMFC) technology to deliver stable, drift-resistant readings across variable ambient conditions. With a nominal capacity of 620 g and readability of 0.01 g, the NV622ZH operates within the Class II accuracy classification per EN 45501 and meets the performance requirements of ASTM E1153 and ISO 9001-compliant weighing processes. Its compact footprint, integrated transport lock, and dual power options (AC or battery) make it suitable for mobile lab workflows, field quality checks, educational labs, and production line sampling where portability and repeatability are prioritized over metrological traceability at Class I levels.
Key Features
- Robust mechanical overload protection rated to 400% of full scale (2480 g), minimizing sensor damage from accidental overloading
- Integrated transport lock mechanism safeguards the load cell during shipment and relocation
- Stable weighing response with typical stabilization time ≤1.0 second under standard laboratory conditions (23 °C ±5 °C, <70% RH)
- IP42-rated enclosure provides resistance to dust ingress and vertical water droplets, supporting use in semi-industrial settings
- Four programmable weighing units (g, oz, ct, dwt) plus eight additional units (lb, ozt, GN, momme, tola, tael HK/SG, tl TH, kg) for global workflow compatibility
- Auto-zero tracking and automatic internal zero calibration on power-up ensure baseline consistency without user intervention
- Backlit LCD display with 18-mm digit height ensures legibility in low-light or high-glare environments
Sample Compatibility & Compliance
The NV622ZH accommodates samples up to 620 g with dimensions compatible with standard 120 mm × 120 mm weighing pans (pan not included). It supports routine solid, granular, and powdered sample handling — including pre-weighing, formulation, inventory counting, and gross/net/tare operations. While not certified for GLP/GMP critical applications requiring audit trails or 21 CFR Part 11 compliance, its performance aligns with ISO/IEC 17025 clause 6.4.7 for equipment suitability in testing laboratories performing non-critical mass determinations. The balance complies with CE marking directives (2014/30/EU EMC, 2014/35/EU LVD) and RoHS 2011/65/EU material restrictions.
Software & Data Management
The NV622ZH features RS232 serial interface (standard) for direct connection to PCs, label printers, or data loggers. Optional OHAUS AC software (v3.0+) enables real-time data streaming, batch export to CSV/Excel, and customizable report templates. Though lacking built-in memory or user-accessible audit trail functionality, the device supports external timestamping via host system integration. For environments requiring electronic record integrity, third-party middleware solutions compliant with ALCOA+ principles may be deployed to capture and archive weighing events externally.
Applications
- Academic teaching labs: stoichiometric preparation, density estimation, and student-led gravimetric analysis
- Quality control checkpoints: incoming raw material verification, component count-by-weight, and packaging weight validation
- Field service technicians: on-site calibration verification, tool inventory reconciliation, and maintenance kit assembly
- Veterinary and agricultural extension: feed ration formulation, seed lot sampling, and small-animal dosing support
- Small-scale manufacturing: adhesive mixing ratios, coating thickness estimation via mass loss, and PCB component sorting
FAQ
What is the recommended calibration frequency for the NV622ZH?
Calibration should be performed before first use, after relocation, following exposure to mechanical shock or temperature extremes, and at least once per shift in production environments. External calibration using Class M2 weights (or better) is required.
Does the NV622ZH support internal calibration?
No — this model relies exclusively on external calibration with certified weights. Internal calibration is not available.
Can the balance operate solely on batteries?
Yes — four AA alkaline or NiMH batteries provide up to 120 hours of continuous operation under typical usage; battery life varies with backlight usage and environmental temperature.
Is the NV622ZH suitable for use in a fume hood?
It may be used in a fume hood if airflow is laminar and velocity remains below 0.2 m/s at the pan surface; however, no dedicated draft shield is supplied, and performance may degrade under turbulent conditions.
What does “400% overload protection” mean in practice?
The mechanical stop system prevents permanent deformation of the load cell when loads up to 2480 g are applied momentarily — but sustained loading beyond 620 g will trigger overload indication and halt measurement.
