Automatic Oil Acid Value Tester | VS-9801

Products Details

Oil acid value is an important routine inspection item for transformer oil and turbine oil. As oil ages during service, oxidation products and acidic compounds may increase. A rising acid number can indicate oil deterioration, contamination, or operating stress, and it can affect insulation performance, corrosion risk, and long-term equipment reliability. For this reason, acid value measurement is widely used in oil condition monitoring programs for transformers, turbines, reactors, capacitors, and other oil-filled equipment.

The VS-9801 Automatic Oil Acid Value Tester is developed for automatic acid number measurement in laboratory and maintenance environments. The instrument uses the acid-base neutralization principle as its measurement framework and integrates optical, mechanical, electrical, and chemical control technologies. It is controlled by a microcomputer system and uses automatic background blank deduction and titration endpoint judgment to support consistent measurement results.

Compared with manual titration, the VS-9801 reduces repeated operator work during reagent addition, stirring, titration, and endpoint judgment. After sample preparation, the instrument can automatically complete the test process and display the acid value result. This makes it suitable for laboratories that test multiple oil samples every day, as well as field service teams that need repeatable acid number data for maintenance decisions.

The tester can measure 1 to 3 samples according to user selection. Before each test, the operator sets the active cup positions on the touch screen. Each sample cup receives 10.0 mL of oil sample and a magnetic stirring bar. During the analysis, the system automatically adds extraction liquid and neutralization liquid, stirs the sample, performs titration, determines the endpoint, and saves the test result.

The instrument uses special reagent bottles for extraction liquid and neutralization liquid. The reagent storage container is made of glass, helping avoid contamination from plastic additives. During normal operation, the user does not need to directly contact organic solvent, which is useful for reducing chemical exposure in routine oil testing work.

The VS-9801 is equipped with a large color touch LCD and full Chinese display interface. It can save up to 35 groups of results and print related test data through the built-in printer. This supports practical laboratory record keeping and gives technicians a simple way to review or output historical test results.

Specifications

Technical Parameters
Item	Specification
Product model	VS-9801
Product type	Automatic Oil Acid Value Tester
Test method	Acid-base neutralization titration
Applicable oil samples	Transformer oil, turbine oil, and related oil samples
Sample capacity	1 to 3 samples per test cycle
Sample volume	10.0 mL per oil cup
Average analysis cycle	About 2 minutes per oil sample
Linear range	0.001 to 0.400 mgKOH/g
Correlation coefficient	0.999 to 0.9998
Recovery rate	98% to 103%
Minimum resolution	0.001 mgKOH/g
Repeatability	2% to 5% RSD
Accuracy, 0.001 to 0.100 mgKOH/g	±0.003 mgKOH/g
Accuracy, 0.100 to 0.400 mgKOH/g	2% to 5% of reading
Display	Large color touch LCD
Result storage	Up to 35 groups
Operating temperature	0°C to 40°C
Relative humidity	≤85%
Power supply	AC 220 V ±10%
Power frequency	50 Hz ±5 Hz
Power consumption	<150 W
Dimensions	430 mm × 370 mm × 190 mm
Net weight	About 9 kg

Product Guide

Before starting the VS-9801, place the instrument on a stable laboratory bench and connect it to the specified AC power supply. After the power switch is turned on, the color touch screen displays the startup page. The operator can enter the initialization page to prepare the reagent system before formal sample testing.

Pipeline cleaning and exhaust are important preparation steps. The operator should place a waste cup in the correct position and start the system cleaning function, allowing the instrument to clean the extraction and neutralization liquid pipelines. If visible bubbles remain in the reagent pipeline, the extraction exhaust and neutralization exhaust functions should be used until no obvious air bubbles are discharged. This helps maintain stable reagent delivery and improves titration repeatability.

Before testing, the operator enters the setting page and selects the active cup positions. The VS-9801 can test 1, 2, or 3 samples according to the actual sample quantity. Clean oil cups should be placed horizontally in the selected cup positions. Each cup should receive 10.0 mL of the oil sample, and one magnetic stirring bar should be added to each sample cup. After the dark chamber cover is closed, the test can be started from the touch screen.

During the test, the instrument automatically controls liquid adding, stirring, titration, and endpoint determination. The screen displays the current test status, such as the selected cup under test, titration in progress, endpoint value, and test completion information. After testing is complete, the acid value result is saved automatically.

Users can enter the review interface to check stored data. The instrument can store up to 35 groups of measurement results, and the operator can turn pages to view previous data. Required results can be printed through the built-in printer for laboratory records, equipment files, or maintenance reports.

After daily use, the extraction liquid and neutralization liquid pump pressure plates should be loosened to prevent long-term deformation or sticking of the pump tubing. The reagent pipelines should be cleaned with anhydrous ethanol to prevent precipitation from blocking the pipeline or micro titration needle. Reagents should be sealed and stored at room temperature away from light when not in use.

Features

• Supports automatic acid value measurement for transformer oil and turbine oil.
• Measures 1 to 3 oil samples according to selected cup positions.
• Automatically completes reagent adding, stirring, titration, and endpoint judgment.
• Provides acid-base neutralization measurement for oil acid number analysis.
• Includes background blank deduction to improve measurement consistency.
• Displays operating parameters and test results on a color touch screen.
• Stores up to 35 groups of test results for later review.
• Includes built-in printing for acid value test records.
• Uses glass reagent containers to reduce contamination from plastic additives.
• Reduces direct operator contact with organic solvents during routine testing.
• Provides automatic cleaning and exhaust functions for reagent pipelines.
• Supports result review by page and selected report printing.
• Includes magnetic stirring for sample mixing during titration.
• Provides compact benchtop structure for laboratory and maintenance use.

Application Scenarios

The VS-9801 is suitable for transformer oil condition monitoring in power utilities and substations. Acid value testing helps maintenance personnel track oil aging and determine whether oil treatment, replacement, or further laboratory analysis is required. For substations managing many oil-filled transformers, an automatic tester can make routine sample testing more consistent and less labor-intensive.

In power plants, the instrument can be used for turbine oil acid value testing. Turbine oil operates under heat, oxidation, and mechanical stress, so regular acid number measurement supports lubrication management and equipment maintenance planning. The automatic titration process helps laboratory staff handle repeated samples more efficiently.

For industrial plants, the VS-9801 supports oil inspection for transformers, reactors, capacitors, and other oil-filled electrical equipment. Maintenance departments can use acid value data together with moisture, dielectric strength, and dissolved gas analysis results to evaluate the overall condition of insulating oil.

For oil testing laboratories and service contractors, the three-cup structure is useful when testing batches of customer samples. The instrument supports sample sequence testing, automatic result storage, and printed reports, which helps create a clear workflow from sample preparation to final documentation.

For equipment manufacturing and acceptance testing, the tester can be used to confirm oil quality before filling, shipment, or commissioning. This is useful for transformer manufacturers, repair workshops, and engineering companies that require measurable oil condition data before equipment delivery.

Applications

The VS-9801 Automatic Oil Acid Value Tester is used in power utilities, transformer maintenance departments, oil testing laboratories, power plants, industrial enterprises, transformer repair workshops, electrical testing companies, and quality inspection departments. It is suitable for routine acid number measurement of transformer oil, turbine oil, and other applicable oil samples.

Typical test objects include transformer insulating oil, turbine lubricating oil, oil from reactors, oil-filled capacitors, oil-filled circuit breakers, and other mineral oil systems where acid value is used as a condition indicator. The tester is suitable for both routine maintenance programs and sample-based laboratory inspection.

For international B2B product positioning, the VS-9801 can be described as an automatic oil acid value tester, transformer oil acid number tester, oil acidity analyzer, automatic oil titrator, insulating oil acid value meter, and turbine oil acid value test instrument.

Customer Case

A transformer maintenance laboratory was responsible for routine oil testing from multiple substations. The laboratory previously used manual titration for oil acid value measurement, which required repeated reagent handling and depended heavily on operator judgment at the titration endpoint. As sample volume increased, the team needed a more repeatable and easier workflow.

The laboratory introduced the VS-9801 Automatic Oil Acid Value Tester for transformer oil acid number testing. Before each batch, the technician completed system cleaning, reagent exhaust, cup position setting, and sample preparation. Three oil samples were placed in the selected cups, each with 10.0 mL of oil sample and a magnetic stirring bar. The instrument then automatically completed reagent adding, stirring, titration, and endpoint judgment.

The stored results allowed the technician to review recent measurements, while the built-in printer provided test records for each batch. Because the operator no longer needed to handle the full titration process manually, the laboratory reduced repetitive work and improved consistency between different users.

After several months of use, the maintenance team used acid value trends together with other oil test data to identify transformers requiring closer oil condition monitoring. The VS-9801 became part of the laboratory’s routine insulating oil inspection workflow.

FAQ

• What is the VS-9801 used for?
  The VS-9801 is used to measure the acid value, also called acid number, of transformer oil, turbine oil, and related oil samples. It helps users evaluate oil aging and condition in power and industrial equipment.
• What measurement principle does the instrument use?
  The instrument uses acid-base neutralization titration. It automatically adds reagent, stirs the sample, performs titration, determines the endpoint, and calculates the acid value.
• How many samples can it test at one time?
  The VS-9801 can be set to test 1 to 3 samples according to the selected cup positions. This makes it suitable for both single-sample testing and small batch testing.
• What is the measurement range?
  The linear measurement range is 0.001 to 0.400 mgKOH/g, with a minimum resolution of 0.001 mgKOH/g.
• How long does one oil sample test take?
  The average analysis cycle is about 2 minutes per oil sample, according to the manual.
• Does the operator need to manually judge the endpoint?
  No. The VS-9801 uses automatic endpoint logic judgment, which reduces dependence on manual visual judgment during titration.
• Can the tester store and print results?
  Yes. The instrument can store up to 35 groups of test results and print selected data through the built-in printer.
• What sample volume is required?
  Each oil cup requires 10.0 mL of oil sample for testing.
• What maintenance is required after use?
  After use, the pump pressure plates should be loosened, and the extraction and neutralization pipelines should be cleaned with anhydrous ethanol. Reagents should be sealed and stored at room temperature away from light.
• Who typically uses this instrument?
  Typical users include power utilities, substations, power plants, transformer repair workshops, industrial maintenance departments, oil laboratories, and electrical testing service companies.

Weshine Advantages

Weshine Electric provides oil testing and electrical diagnostic instruments for power utilities, substations, industrial users, laboratories, and testing service providers. For the VS-9801 Automatic Oil Acid Value Tester, Weshine supports customers with model selection, reagent and consumable guidance, operation documentation, application consultation, and after-sales service.

Oil analysis work depends on stable instruments, repeatable procedures, and clear records. The VS-9801 is designed to help users reduce manual titration workload, standardize routine oil acid value testing, and keep test results available for maintenance decisions and equipment archives.

For overseas distributors and project buyers, Weshine can provide product information, technical parameter confirmation, and application support for procurement documents, laboratory setup, training, and resale preparation. The VS-9801 is suitable for customers looking for an automatic transformer oil acid value tester or oil acidity analyzer for power equipment maintenance.