Mettler Toledo AB304-S Analytical Balance – Used & Refurbished
The Mettler Toledo AB304-S Analytical Balance is a refurbished analytical laboratory balance offering 320 g weighing capacity and 0.1 mg readability. It is designed for reference-standard preparation, quantitative chemistry, and analytical quality control. American Instrument Exchange provides inspected, tested laboratory weighing equipment backed by a 90-day warranty.
The enclosed draft shield, full-range tare and application functions for percent weighing, counting and dynamic weighing support traditional analytical workflows. For laboratories evaluating a used balance, the key purchasing considerations are not only capacity and readability, but also the condition of the weighing mechanism, installed accessories, adjustment system and performance after shipment.
Key Features
- 320 g maximum weighing capacity or specified range
- 0.1 mg readability
- Verify installed adjustment
- The enclosed draft shield, full-range tare and application functions for percent weighing, counting and dynamic weighing support traditional analytical workflows.
- Refurbished and performance tested by American Instrument Exchange
- 90-day warranty included from American Instrument Exchange
Overview
The Mettler Toledo AB304-S Analytical Balance addresses the need for dependable mass determination in reference-standard preparation, quantitative chemistry, and analytical quality control. Its 0.1 mg display increment helps operators resolve small changes in load, while the 320 g weighing range determines the size of samples and containers it can accommodate. Selecting the correct combination is essential: an instrument with high resolution but insufficient capacity may not support the intended vessels, while a larger-capacity model with coarse readability may not suit sensitive procedures.
With 320 g capacity at 0.1 mg readability, the AB304-S provides more load capacity than many 120 g or 220 g analytical balances. These characteristics distinguish the model from generic digital scales and should be considered alongside adjustment requirements, installation conditions and available interfaces. A refurbished balance can provide a cost-effective solution for laboratories replacing aging equipment, expanding capacity or equipping additional workstations.
Common Applications
Typical uses include reference-standard preparation, quantitative chemistry, and analytical quality control, preparation of working solutions, weighing laboratory consumables, and documenting masses for repeatable experimental procedures. Weighing analytical reference materials, accurately dispensing small amounts of solid reagents, preparing standard solutions and supporting quantitative assays all benefit from careful balance selection.
The Mettler Toledo AB304-S Analytical Balance can also support training, method development and quality-control checks when the selected test masses are appropriate for its operating range. Before adopting a new method, confirm that the instrument's actual repeatability and measurement uncertainty meet the procedure's acceptance criteria.
Ideal Laboratory Environments
Research institutions, pharmaceutical and biotechnology facilities, chemical laboratories, environmental testing groups, universities and industrial quality-control departments may find this model useful. Its suitability depends on the actual sample sizes, laboratory throughput and degree of documentation required.
For shared laboratories, written operating instructions help standardize taring, adjustment and cleaning practices between users. Regulated facilities should incorporate the balance into their existing equipment qualification, calibration and record-retention procedures rather than assuming that a manufacturer's feature list alone establishes compliance.
Weighing Performance and Repeatability
The published capacity is 320 g, with 0.1 mg readability. Available technical information identifies repeatability as 0.1 mg and linearity as 0.4 mg; where a value is marked for verification, it should not be treated as a guaranteed specification for the particular refurbished instrument. Repeatability describes variation across repeated weighings of the same load, while linearity evaluates agreement across the instrument's range.
Readability is not the same as a qualified minimum sample weight. Where USP or other uncertainty limits apply, establish the actual minimum from measured repeatability under the laboratory's conditions. A nominal 0.01 mg or 0.1 mg display increment does not by itself establish compliance. The most useful performance test for a prospective application is one that uses representative masses, suitable reference weights and the same environmental conditions expected during normal operation.
Model-Specific Features and Operating Benefits
The enclosed draft shield, full-range tare and application functions for percent weighing, counting and dynamic weighing support traditional analytical workflows. With 320 g capacity at 0.1 mg readability, the AB304-S provides more load capacity than many 120 g or 220 g analytical balances.
The manufacturer lists repeatability of 0.1 mg and linearity of 0.4 mg for this model. Confirm model suffixes and the installed hardware before relying on optional accessories or special weighing modes. A similar-looking balance from the same manufacturer may have a different adjustment system, range or communications package.
Calibration and Adjustment
The listed adjustment approach is Verify installed adjustment. Adjustment brings the balance's response into agreement with its reference, whereas calibration or performance verification documents how the instrument behaves against known test masses. The two procedures are related but should not be treated as interchangeable.
Use suitable reference weights, allow adequate warm-up and follow the applicable manufacturer procedure. For laboratories using the instrument in regulated or high-precision applications, document the weight identification, test points, environmental conditions and acceptance limits. After relocation or shipping, repeat relevant checks before reporting critical measurements.
Draft Protection and Environmental Stability
Close the draft shield during sensitive measurements and allow the reading to stabilize. Air currents, room temperature gradients, vibration and electrostatic charge can contribute disproportionately to apparent changes in mass at this resolution. For analytical work, fingerprints, moisture exchange and static charge can influence small samples. Use clean vessels, handle them with tools where practical, and avoid weighing warm containers immediately after removal from ovens or incubators.
An appropriate work surface, stable temperature and controlled handling technique are often as important as nominal resolution. If a reading drifts or fails to settle, investigate airflow, vibration, electrostatic effects, warm samples and incorrect leveling before concluding that the weighing mechanism requires adjustment.
Display, Controls and Data Documentation
Routine use begins with confirming a stable zero indication, selecting the required unit, placing a clean vessel on the pan and applying tare before adding the sample. Record results only after the stability indication or equivalent measurement criterion is satisfied. Where the instrument supports counting, percent weighing, formulation or data transfer, configure those functions to match the laboratory's procedure.
For electronic records, verify the interfaces physically installed on this refurbished unit and the compatibility of any printer or computer connection. Manual transcription may be adequate for low-throughput work, but documented data transfer can reduce recording errors when a compatible interface is available. Optional hardware should not be assumed to be included.
Key Specifications
| Specification |
Details |
| Manufacturer / model |
Mettler Toledo AB304-S Analytical Balance |
| Equipment type |
analytical balance |
| Maximum capacity |
320 g |
| Readability |
0.1 mg |
| Repeatability |
0.1 mg |
| Linearity |
0.4 mg |
| Adjustment |
Verify installed adjustment |
| Weighing pan |
Verify installed pan |
| Minimum sample weight |
Determine under actual laboratory conditions |
| Power supply |
Confirm label and included adapter |
| Exterior dimensions / weight |
Confirm installed configuration |
| Condition |
Used and refurbished |
| Warranty |
90 days from American Instrument Exchange |
Specifications are based on available manufacturer or model references and existing AIE product information. Optional equipment and performance of an individual used unit should be confirmed before ordering.
Refurbishment and Performance Testing
American Instrument Exchange inspects and cleans used laboratory balances and evaluates relevant weighing functions before shipment. Checks may include display and keypad operation, zero and tare response, repeatability with repeated reference loads, linearity at multiple points, and corner-load behavior. Installed adjustment systems, draft shields and communications features are checked as applicable.
The purpose of refurbishment is to provide an operational instrument with documented functional checks, not to imply that every used unit is identical to a new factory instrument. Customers with specialized qualification or acceptance requirements should communicate those needs before purchase. A 90-day warranty is included from American Instrument Exchange.
Shipping and Installation
Protect the weighing cell, draft shield glass and pan during transport. Allow the unit to acclimate before adjustment and verification; temperature differences between the instrument and the room can delay stable high-resolution measurements. Place the balance on a stable surface, install the pan and included accessories, check leveling and perform adjustment or external verification as appropriate.
Before ordering, confirm the supplied power adapter, pan, draft shield, interface accessories and any calibration weights needed for the laboratory's procedures. Shipping arrangements should account for the sensitivity of the weighing mechanism and the possibility of fragile enclosure components.
Related Laboratory Equipment
Explore additional laboratory balances from American Instrument Exchange, including analytical, semi-micro and precision models. Laboratories expanding sample-preparation capabilities can also source centrifuges, water baths, incubators, laboratory refrigerators and laboratory freezers.
Frequently Asked Questions
What is the capacity of the Mettler Toledo AB304-S Analytical Balance?
The stated maximum capacity or operating range is 320 g. Include the tare vessel when calculating the load.
What is the readability?
The model displays mass in 0.1 mg increments within its applicable weighing range.
Is this model suitable for reference-standard preparation, quantitative chemistry, and analytical quality control?
It is designed for those types of applications, provided its actual repeatability, capacity and uncertainty meet the laboratory's method requirements.
Does it adjust automatically?
The documented adjustment approach is Verify installed adjustment. Confirm the actual installed configuration and perform external verification according to laboratory procedures.
How should minimum sample weight be determined?
Measure repeatability under the laboratory's conditions and apply the relevant uncertainty or method criteria. Display readability alone is not sufficient.
What testing is performed before shipment?
American Instrument Exchange evaluates applicable weighing and operating functions, including repeatability, linearity, corner-load response, controls and installed adjustment features.
Is a warranty included?
Yes. A 90-day warranty is included from American Instrument Exchange.
