| System | Forced air convection | 
  
    | Operating temperature range | -10°C~+50°C | 
  
    | Temperature adjustment accuracy | ±0.3°C (refrigerator in continuous operation) / ±1.0°C (refrigerator in cycle operation) | 
  
    | Temp. distribution accuracy | ±1.0°C (refrigerator in continuous operation at 37°C) | 
  
    | Max. temp. reaching time | 20~50°C ~20min | 20~50°C   ~30min | Data unavailable | 
  
    | Minimum temp. reaching time | 20~-10°C   ~ 45min 
 | 20~-10°C   ~55min | 20~-10°C   ~65min | Data unavailable | 
  
    | Interior material | Stainless steel | 
  
    | Exterior material | Chrome free electronic galvanized plated steel plate chemical proof baking finish | 
  
    | Observation window | --- | W516 x H416mm (with key) | --- | Data unavailbale | 
  
    | Heat insulation material | Styrene foam | 
  
    | Refrigerator | Air-cooled fully closed compressor 250W | Air-cooled fully closed compressor 300W | 
  
    | Refrigerator medium | R134A | R404A | 
  
    | Defrosting mechanism | Manual ON / Auto OFF, Timer operation, Cycle operation | 
  
    | Blower fan | Axial fan | 
  
    | Heater | Iron-chrome wire heater: 550W | Iron-chrome wire heater: 750W | 
  
    | Sensor | Platinum resistance temperature detector: Pt100Ω (temp. controller), K-thermocouple (overheat prevention device) | 
  
    | Cable port (right side) | I.D.: 30mm | I.D.: 50 mm | I.D.: 30 mm | I.D.: 30 mm | 
  
    | Temperature control | PID control | 
  
    | Temperature setting | Digital setting with ▲▼ keys | 
  
    | Temperature display | Measured temperature: 4-digit orange LED digital display + VFD fluorescent display | 
  
    | Timer / timer resolution | 0 min. ~ 999 hrs. 59 min. / 1 min. | 
  
    | Operation function | Fixed temperature, auto stop, auto start, program (up to 32 steps, repeat operation) | 
  
    | Additional functions | Timer function (accumulated time to 49,999 hrs), calibration off-set function, clock display | 
  
    | Safety device | Self diagnostic function (Temp. sensor error, Heater disconnection, SSR short-circuit, Main relay error, Automatic overheat prevention function), Key lock, Over current ELB, Overheat prevention device | 
  
    | Internal dimensions W x D x H | 600 x 477 x 500 mm | 600 x 477 x 1000 mm | 
  
    | External dimensions W x D x H | 710 x 645 x 913 mm | 710 x 645 x 1630 mm | 
  
    | Internal capacity | 143L | 286L | 
  
    | Shelf plate load | 15kg / pc. | 
  
    | Shelf rest step number / pitch | 13 steps / 30mm | 23 steps / 30mm | 
  
    | Power supply (50/60Hz) | AC115V 9A (with plug) AC220V 5.5A (no plug, round terminal)
 | AC115V 10.5A (with plug) AC220V 7.5A (no plug, round terminal)
 | AC115V 10.5A (with plug) AC220V 6A (no plug, round terminal)
 | AC115V (with plug) AC220V (no plug, round terminal)
 | 
  
    | Weight | ~89kg | ~ 120kg | 
  
    | Included accessories | Shelf and brackets (stainless steel punched metal) | 
  
    | 3 pcs. shelves / 6 pcs. brackets | 5 pcs. shelves / 10 pcs. brackets | 
  
    | Door keys | --- | 2 keys | --- | 2 keys | 
  
    | Optional accessories | Stand, additional shelf, cable port (ø30/50mm), recorder, warning light combination (stand-by/operation/error), temperature output terminal (4-20mA), external alarm output terminal, time up output terminal | 
  
    | List Price | $ 5,110 | $ 5,660 | $ 7,105 | $ 8,915 |