Pond Engineering designed this stirred liquid bath system to provide  user-friendly  calibrations over the range of -80°C to +300°C in a stable, uniform environment. Three optional configurations allow the user to tailor the system to meet the needs of their particular calibration workload. The  base system is comprised of two well modules positioned side by side in a single cabinet and covers the range of temperatures from -80°C to + 300°C. The low-temperature well is capable of operating between -80°C and +70°C and will typically utilize a water/glycol solution and methanol bath fluids to cover that range. The high-temperature well operates between +50°C and +300°C using silicone oils of various viscosities.

An interactive user interface on a sloping front panel provides convenient system control in a stand-alone configuration, and can be configured to display in either °C or °F. The system setpoint can be set directly (no additional variables or verniers to tweak) using the front panel interface. Optional remote interface  allow users to integrate the K61 into an automated calibration system, dramatically increasing throughput and reducing the cost of calibrations. 

The coaxial, counter-flow design affords extraordinary gradient suppression, both axially and radially. A continuous flow of thermally-conditioned and homogenized bath fluid moves upward through the inner well and flows back in an annular space completely surrounding the inner well to the thermal conditioning/stirring zone. This flow is achieved by utilizing a custom-designed brushless DC motor with a wet rotor and impeller, eliminating the need for dynamic mechanical seals. 

Pond Engineering’s microprocessor-based controller utilizes PRTs with 24-bit AC excitation resistance ratiometric signal conditioning—not thermocouples—for unprecedented accuracy and control stability.

Both wells in the K61 are fitted with expansion volumes which accommodate the expansion and contraction of bath fluids, allowing the system to function across wide temperature ranges with minimal user interaction.

  • System Setpoint Range -80°C to +70°C (low)
    -30°C to +70°C (mid)
    +50°C to +300°C (high)
    Stability Better than ±0.006°C over 30 minutes
    Axial Gradients Less than 0.003°C in inner well
    Setpoint Resolution 0.01°(C or F)
    Setpoint Accuracy Better than ±0.3°C in inner well
    Calibration Volume 300 Series Stainless Steel
    ≈2.9" I.D.
    ≈12" (30.5 cm) deep
    ≈18" (45.7 cm) deep (K61D Models)
    Power Requirements 120/240 Volts
    10 Amps max.
    A.C. 60 Hz.
    Cabinet Physical Dimensions 18" (46 cm) wide
    20" (51 cm) deep
    36" (92 cm) high
    42" (107 cm) high (K61D Models)
  • 1. 2.6” (65mm) well opening
    2. Coaxial counter-flow design to achieve stability better than ±0.003 °C over 30 minutes
    3. Bottom-stirring wet rotor impeller eliminates need for dynamic seals and provides excellent axial and radial uniformity (better than ±0.005 °C)
    4. User-controlled motor speed to allow adjustment for optiumum flow rate
    5. Expansion volume to accommodate changes in fluid volume during system operation at varying setpoints, preventing overflow onto cabinet top
    6. Bath fluid level pumped above cabinet top, ideal for calibrating liquid-in-glass thermometers


Safety Data Sheets