The following data describe the MSTITR20VSWISS Karl Fischer coulometer. This instrument uses the coulometric titration principle for trace moisture determination. All values are measured under the manufacturer‘s standard test conditions.

Technical Specifications

• Model number: MSTITR20VSWISS

• Instrument type: Karl Fischer coulometer (coulometric titrator)

• Titration method: Coulometric Karl Fischer titration

• Water measuring range: 10 µg to 20 mg

• Polarization current accuracy: ±0.2 µA

• Working current settings: 10 mA, 20 mA, 50 mA, 100 mA

• Working current accuracy: 0.5%

• Accuracy: ± (5% + 3) µg

• Repeatability: ±3%

• Generator cell type: With diaphragm

• Display: LCD screen

• Data export: RS‑232 communication interface for printer connection

• Settable parameters: Measurement unit, polarization current, generator current, endpoint potential, stop criterion, and more

• Reset function: Automatically resumes all settings back to factory default options

• Selectable units: µg, mg, %, mg/L, g/L, etc.

• Power supply: AC adapter, 200‑240 VAC input; YW‑904W 9V/800mA regulated power supply (European plug)

• Dimensions: 300 × 235 × 100 mm

• Weight: 3 kg

• Compliance: Meets ISO, ASTM, DIN, BS, and JIS standards for Karl Fischer moisture measurement

• Applications: Suitable for solid, liquid, and gas samples

Included accessories (standard packing)

• MSTITR20VSWISS Karl Fischer coulometer main unit

• JB‑11 stirrer

• Electrolytic cell (including inlet screw nut and puncture‑resistant silicone sheet)

• Electrolysis electrode (includes film holder)

• Indicator electrode

• Dryer (SC5.111.007)

• Power cord (European standard)

• Printer connection cable

• Fuse 0.5A (2 pieces)

• YW‑904W 9V/800mA regulated power supply (European plug)

• Electrolytic cup fixed ring (SC5.108.020)

• Stirrer bar (small) – 3 pieces

• Fixed rod (SC8.123.035)

• Puncture‑resistant silicone sheet (SC8.370.298) – 20 pieces

• Micro sampler (1 mL)

• Micro sampler (0.1 mL)

• Membrane frame (SC5.156.017) with O‑ring fluoro rubber – 2 sets

• Vacuum silicone (Great Wall 7501)

• Allochroic silica gel (500g)

• Instruction manual (MSTITR20VSWISS, JB‑11)

• Packing list

• Certificate

Key benefits for trace moisture analysis

The specifications above translate into practical improvements for trace moisture determination. Each point below connects a feature to a measurable outcome.

Coulometric titration for trace moisture detection – The coulometric method generates iodine electrochemically, eliminating the need for titrant standardization. A laboratory measuring moisture in the 10µg‑20mg range achieves higher precision than volumetric methods. The ±3% repeatability ensures confidence in single‑digit parts‑per‑million results.

Diaphragm generator cell for stable performance – The generator cell with diaphragm separates the anodic and cathodic compartments, preventing side reactions. A pharmaceutical QC laboratory measuring residual moisture in lyophilised products runs stable titrations without drift. The diaphragm extends the life of the generator electrode.

Flexible working current settings – The user selects 10mA, 20mA, 50mA, or 100mA generator current. A researcher measuring ultra‑trace moisture in dry gases uses 10mA for slow, precise titration. A QC technician measuring higher moisture in polymers uses 100mA for faster analysis. One instrument adapts to the sample.

LCD display with programmable parameters – The LCD screen shows titration progress, endpoint potential, and results. The operator sets measurement units, polarization current, generator current, endpoint potential, and stop criterion. No external computer is required for basic operation.

RS‑232 data export for audit‑ready records – The RS‑232 communication interface connects to a printer for hard‑copy reports. A quality control laboratory preparing for an internal audit prints the titration report directly. The data transfer is simple and reliable.

Reset function for quick recovery – The reset feature automatically restores all settings to factory default options. A new operator or a trainee returns the instrument to a known state with a single action. No risk of incorrect parameters causing failed titrations.

Common frustrations with coulometric Karl Fischer titration – and how this instrument solves them

Pain point: Time‑consuming titrant standardization.
Volumetric Karl Fischer titrators require daily or weekly titer determination using a water standard. The MASTER SCIENCE MSTITR20VSWISS Karl Fischer coulometer (a reagent‑free titration system with electrochemical iodine generation) eliminates titer standardization entirely. The instrument generates iodine on demand. A laboratory running 20 moisture determinations per day saves 30 minutes of daily standardization time.

Pain point: Poor precision at trace moisture levels.
Volumetric methods struggle below 1mg water due to burette resolution limits. The same MASTER SCIENCE MSTITR20VSWISS Karl Fischer coulometer (with 10µg‑20mg range and ±3% repeatability) measures moisture in the parts‑per‑million range. A petrochemical laboratory testing transformer oil at 5‑10ppm obtains consistent results. A pharmaceutical QC lab measuring residual moisture at 0.1% sees clear differentiation between batches.

Pain point: No printed records for quality audits.
A quality manager needs documented evidence of each titration. The MASTER SCIENCE MSTITR20VSWISS Karl Fischer coulometer (with RS‑232 printer connection for direct report printing) connects to a standard printer. The operator prints a report showing the sample weight, water content, titration time, and result. The printed slip goes directly into the batch record. No manual transcription, no missing entries.

Pain point: Complex parameter setup confuses new operators.
Multiple settings for polarization current, generator current, and endpoint potential intimidate inexperienced users. The MASTER SCIENCE MSTITR20VSWISS Karl Fischer coulometer (with a one‑step reset feature to factory default settings) allows a supervisor to restore the instrument to a known state. A trainee who changes parameters accidentally reverts to the default method with a single action. Training time is reduced significantly.

Pain point: Cross‑contamination between samples.
The same titration cell used for multiple samples can retain moisture from previous runs. The MASTER SCIENCE MSTITR20VSWISS Karl Fischer coulometer (with a diaphragm generator cell and electrolytic cell design) maintains separation between the anodic and cathodic compartments. The operator rinses the cell between samples. The diaphragm prevents iodine migration, ensuring each titration starts from a clean baseline.

Which laboratories choose the MSTITR20VSWISS

Pharmaceutical quality control laboratories – Measure residual moisture in active pharmaceutical ingredients, excipients, and finished dosage forms (tablets, capsules, lyophilised powders). The 10µg‑20mg range meets pharmacopoeia requirements for trace moisture determination. The RS‑232 data export supports audit documentation.

Petrochemical and lubricant laboratories – Determine water content in transformer oils, hydraulic fluids, lubricating oils, and fuels. The coulometric method provides the precision needed for trace moisture in dry oils. The instrument handles liquid samples via direct injection.

Gas and specialty chemical manufacturers – Measure moisture in compressed gases, refrigerant gases, and ultra‑high‑purity chemicals. The puncture‑resistant silicone sheet allows injection of gaseous samples into the titration cell. The 10µg lower limit detects moisture at the parts‑per‑million level.

Polymer and plastic manufacturers – Control moisture in resin pellets, films, and moulded parts. The instrument handles solid samples via oven or extraction methods. The selectable units (µg, mg, %, ppm) match reporting requirements.

Academic and research laboratories – Teach Karl Fischer coulometric titration principles to students. The LCD display and simple parameter setup reduce student errors. The instrument supports method development for novel sample types.

Food and beverage testing laboratories – Measure moisture in dried foods, spices, and powdered milk. The coulometric method provides the precision needed for low‑moisture food products. The 20mg upper range covers typical moisture levels in dehydrated foods.

Physical configuration and daily operation

Installation – The instrument stands on a bench (300 × 235 × 100 mm) weighing 3 kg. The electrolytic cell sits on the JB‑11 stirrer. The power supply is a 9V/800mA regulated adapter with European plug.

Setting up the titration cell – Assemble the electrolytic cell with the electrolysis electrode (with diaphragm) and the indicator electrode. Connect the dryer to the cell inlet. Fill the cell with Karl Fischer reagent. The stirrer bar is placed in the cell.

Preparing the instrument – Connect the power supply, printer cable, and stirrer. Turn on the instrument. The LCD display shows the default method. The operator sets the measurement unit, polarization current, generator current, and stop criterion using the keypad.

Running a titration (liquid sample) – Inject the liquid sample through the puncture‑resistant silicone sheet using the micro sampler (1mL or 0.1mL). The instrument starts the titration automatically. The display shows the titration curve and the water content at the endpoint.

Running a titration (solid or gas sample) – For solids, use an oven or extraction method to transfer the moisture into the cell. For gases, inject the gas sample through the silicone sheet. The instrument titrates the water and reports the result.

Data export – Connect a printer to the RS‑232 port. Press the print button after the titration. The printer produces a report showing the sample weight, water content, and titration parameters. Alternatively, the data can be stored and transferred later.

Resetting to factory defaults – If the operator needs to restore the instrument to factory settings, press the reset button or select the reset function from the menu. All parameters revert to default options.

Maintenance and care

Reagent replacement – The Karl Fischer reagent in the electrolytic cell is consumed during titration. Replace the reagent when the titration speed decreases or when the indicator shows exhaustion. The reagent is available from Merck (compatible with coulometric cells).

Electrode maintenance – The electrolysis electrode (with diaphragm) and the indicator electrode are cleaned periodically with a suitable solvent. The diaphragm is checked for clogging. The user manual provides detailed cleaning procedures.

Desiccant replacement – The dryer contains allochroic silica gel (500g supplied). Replace the silica gel when the colour changes from blue to pink (indicating moisture saturation). The supplied vacuum silicone (Great Wall 7501) is used for sealing connections.

Diaphragm replacement – The membrane frame (SC5.156.017) includes an O‑ring fluoro rubber. Replace the diaphragm when the titration speed drops or when the cell shows signs of leakage. Two sets are supplied in the standard packing.

Calibration – The instrument is factory‑calibrated. The user verifies the calibration using a certified water standard. The coulometric method does not require titer determination, but the instrument accuracy should be checked periodically. Annual recalibration is recommended for regulated applications.

Ordering information

The MSTITR20VSWISS ships as a complete kit including:

• MSTITR20VSWISS Karl Fischer coulometer main unit

• JB‑11 stirrer

• Electrolytic cell (with inlet screw nut and puncture‑resistant silicone sheet)

• Electrolysis electrode (with film holder)

• Indicator electrode

• Dryer (SC5.111.007)

• Power cord (European standard)

• Printer connection cable

• Fuse 0.5A (2 pieces)

• YW‑904W 9V/800mA regulated power supply (European plug)

• Electrolytic cup fixed ring (SC5.108.020)

• Stirrer bar (small) – 3 pieces

• Fixed rod (SC8.123.035)

• Puncture‑resistant silicone sheet (SC8.370.298) – 20 pieces

• Micro sampler (1 mL)

• Micro sampler (0.1 mL)

• Membrane frame (SC5.156.017) with O‑ring fluoro rubber – 2 sets

• Vacuum silicone (Great Wall 7501)

• Allochroic silica gel (500g)

• Instruction manual (MSTITR20VSWISS, JB‑11)

• Packing list

• Certificate

The customer must specify the following when ordering:

1. Model number (MSTITR20VSWISS)

2. Power supply type (European plug standard – adapter for other regions may be required)

Reagents (order separately): The MSTITR20VSWISS requires Karl Fischer coulometric reagents. The user should select a compatible reagent from Merck or other suppliers. The reagent is open and can be purchased locally.