| model | ST109A | ST109B | ST109C | ST109D |
| according to the standard | GB5009.34-2022 "Method for Determination of Sulfur Dioxide in Foods", the 2015 and 2020 editions of the "Chinese Pharmacopoeia" for determining sulfur dioxide in traditional Chinese medicines and herbal materials; | |||
| corresponding standard | Method 1 and Method 2 of GB5009.34-2022 | Method 1 and Method 2 of GB5009.34-2022 | Method 1 and Method 2 of GB5009.34-2022 | GB5009.34-2022 Third Method |
| Product positioning | High-end, fully automatic | Standard Edition | cost-effective model | Special machine for steam distillation |
| Sample Quantity | Six (6) | 6 pieces | 8 pieces | Six (6) |
| Flask volume | Conventional double-neck 1000ml flask | Customized double-spout 1000ml flask | Conventional double-neck 1000ml flask | Conventional double-neck 500ml flask |
| Heating method | Far-infrared ceramic heating | Far-infrared ceramic heating | Far-infrared ceramic heating | Built-in steam source for water vapor heating |
| Condenser tube structure | Reflux type, semi-hidden structure | Reflux condenser tube | Reflow type, semi-hidden structure | Serpentine condenser tube |
| Automatic acid addition | Automatic acid addition | Automatic acid addition | Automatic acid addition | Automatic acid addition |
| Nitrogen control | Digital adjustable nitrogen average distribution system | Rotameter (200-2000ml/min) | Rotameter (200-2000ml/min) | Rotameter (200-2000ml/min) |
| cooling method | External cooling water circulation machine | Built-in compressor self-circulating cooling system | External cooling water circulation machine | External cooling water circulation machine |
| control method | desktop computer | LCD touch screen | LCD touch screen | LCD touch screen |
| Automatic titration | High-precision syringe pump automatic titration | Nothing | Nothing | —— |
| End point recognition | High-precision visual sensor, fully simulating human eyes, automatically identifies the titration endpoint | Nothing | Nothing | Nothing |
| rated power | 3500W | 3600W | 4500W | 3000W |
| Overall dimensions (mm) | 735×650×670 | 960×575×410 | 940×650×680 | 960×500×730 |
