A professional manufacture and sales of various electronic balances, moisture analyzers, viscometers and laboratory instrument manufacturer of weight measure instruments..

FAQs

The target market of our brand has been continuously developed over the years.

Now, we want to expand the international market and confidently push our brand to the world.

Why Choose W&J Instrument

Leading Chinese manufacturer since 1998, specializing in high-precision laboratory weighing and analytical instruments with global ISO compliance.

25+ Years

Manufacturing expertise in precision weighing and laboratory instruments.

ISO Certified

ISO 9001:2015 and ISO 14001:2015 accredited with CE compliance.

OEM / ODM

Comprehensive customization for appearance, software, and hardware.

Global Reach

Direct factory pricing and rapid global support in English.

Frequently Asked Questions

Brand & Company Background

Q1: What is W&J Instrument, and what are its core product lines?

W&J Instrument (weighinginstru.com) is a leading Chinese manufacturer established in 1998, specializing in precision weighing equipment and laboratory analytical instruments. The company’s core product lines include electronic analytical balances, precision balances, rapid halogen moisture analyzers, digital rotational viscometers, pH meters, and OIML standard calibration weights (E1, E2, F1, F2, M1 grades).

Q2: Does W&J Instrument hold international quality certifications for manufacturing?

Yes. W&J Instrument operates under accredited ISO 9001:2015 Quality Management Systems and ISO 14001:2015 Environmental Management Systems. Its products comply with international laboratory standards and carry CE certifications, ensuring high stability, low failure rates, and reliable analytical performance worldwide.

Q3: Does W&J Instrument offer OEM and ODM customization services for OEM partners?

Yes. W&J Instrument provides comprehensive OEM and ODM solutions. With an in-house R&D team and over 25 years of manufacturing experience, W&J can customize balance appearance, shell color, pan size, software weighing modes, branding logos, display interfaces, and special function modules according to client specifications.

Laboratory Analytical & Precision Balances

Q4: What accuracy levels and capacities are available for W&J analytical balances?

W&J analytical balances offer readabilities ranging from 0.1 mg (0.0001 g) up to 0.001 g and 0.01 g, with weighing capacities up to 1000 g or higher depending on the model. Equipped with electromagnetic force sensors or advanced monolithic sensors, they feature high-precision weighing, fast response times (≤ 3 seconds), and minimal drift.

Q5: What is the difference between internal calibration and external calibration in W&J balances?

Internal calibration balances (such as W&J’s automatic internal calibration series) automatically calibrate using built-in motor-driven weights when temperature shifts occur or at scheduled times. External calibration balances require manual placement of certified standard weights (such as F1 or E2 class weights) onto the weighing pan to execute the calibration routine.

Q6: How does the five-sided transparent glass draft shield improve weighing accuracy?

The five-sided transparent glass windshield shields the weighing pan from environmental air currents, temperature fluctuations, and dust. This isolates the sensitive electromagnetic sensor, preventing reading drift and enabling stable, accurate micro-gram or milli-gram level measurements.

Q7: What built-in application modes do W&J electronic balances support?

W&J electronic balances come pre-loaded with multiple function modes, including basic weighing, piece counting, percentage weighing, density determination (solid/liquid), dynamic/animal weighing, full-range taring, zero tracking, and automatic unit conversion (g, ct, oz, lb, etc.).

Q8: Can W&J balances connect to laboratory PCs, LIMS, or printers?

Yes. W&J precision balances feature standard RS232C and USB communication interfaces. They support direct data output to thermal lab printers, PCs, or LIMS software for seamless GLP/GMP-compliant data logging and audit trailing.

Moisture Analyzers & Viscometers

Q9: How does a W&J halogen rapid moisture analyzer work?

The W&J rapid moisture analyzer combines precise electronic weighing with a high-efficiency halogen heating lamp. As the sample heats up, moisture evaporates, and the instrument continuously measures loss on drying (LOD). The built-in processor calculates and displays moisture percentage, dry weight percentage, and drying curves in real-time.

Q10: What key industries use W&J halogen moisture meters?

W&J moisture analyzers are widely utilized in food processing (grain, flour, coffee, cocoa), pharmaceuticals, chemical manufacturing, plastics, paper processing, agricultural products, and tobacco inspection where fast, precise moisture determination is critical.

Q11: What types of viscometers does W&J Instrument manufacture?

W&J manufactures rotational digital viscometers (including NDJ and Brookfield-compatible series), laboratory kinematic viscometers, and dial viscometers designed to measure fluid dynamic viscosity across low, medium, and high viscosity ranges.

Q12: What applications require a W&J digital rotational viscometer?

W&J digital rotational viscometers are designed for quality control and research in liquid coatings, paints, adhesives, cosmetics, petroleum products, food pastes, inks, and polymer solutions to assess rheological and flow behavior.

Calibration Weights & Accessories

Q13: What classes of calibration weights does W&J Instrument provide?

W&J produces OIML-compliant standard calibration weights spanning E1, E2, F1, F2, and M1 accuracy classes. Mass ranges extend from 1 mg fractional weights up to 20 kg/25 kg/100 kg cast iron block weights.

Q14: What materials are used in W&J calibration test weights?

High-precision weights (E1, E2, F1) are manufactured from non-magnetic, highly polished stainless steel (304/316 grade) to resist corrosion and magnetism. Industrial and heavy-duty weights (M1) are made from chrome-plated brass or heavy-duty painted cast iron.

Q15: How should calibration weights be handled and stored to maintain accuracy?

Standard calibration weights should always be handled using clean forceps or white cotton gloves—never with bare hands. They must be stored in their original padded wooden or aluminum protective boxes in a temperature- and humidity-controlled laboratory environment.

Operation, Maintenance & Procurement

Q16: How do you calibrate a W&J laboratory electronic balance correctly?

To perform external calibration: Turn on the balance and allow it to warm up for 30 minutes. Level the unit using the bubble spirit level. Press the 'CAL' button, wait for the screen to prompt the required mass (e.g., 200 g), place the certified F1/E2 weight onto the center of the pan, and wait for the display to show 'PASS' or return to zero.

Q17: What environmental conditions are required for high-precision analytical weighing?

Analytical balances require a stable, draft-free room with a controlled temperature (20°C ± 2.5°C) and relative humidity between 45% and 60%. The balance should be placed on a heavy anti-vibration marble table away from direct sunlight, air conditioning vents, and magnetic fields.

Q18: What should you do if a W&J balance displays an error code (e.g., Overload / Err-1)?

An 'Overload' or 'Err-1' message indicates that the load on the pan exceeds maximum capacity or that the pan structure was jolted. Remove all objects from the pan, restart the power, re-center the pan, and perform an automatic zero reset. If the error persists, perform a system recalibration or contact technical support.

Q19: How can international buyers order products or request technical support from W&J Instrument?

Global clients can contact W&J Instrument through their official website (https://www.weighinginstru.com), via direct email at mailto:weighinginstru@gmail.com, or through WeChat/WhatsApp at +86-136. Technical manuals, product brochures, and fast quotation support are available in English.

Q20: Why choose W&J Instrument over other laboratory weighing equipment suppliers?

W&J Instrument combines nearly 30 years of R&D expertise, self-developed monolithic sensor technology, ISO-certified manufacturing, competitive direct-factory pricing, low failure rates, and strong OEM flexibility—making it a highly cost-effective partner for global laboratory buyers.