Model 798L Temperature Bath Calibrator. Temperature range -80°C to +125°C
Model 798M Temperature Bath Calibrator. Temperature range -40°C to +125°C
Model 798H Temperature Bath Calibrator. Temperature range ambient to 200°C
The Hydra Range of three baths is a completely new design and development.
Commercial grade 1/3 horse power chillers are used to give maximum cooling and smooth, quiet operation with long term reliability. The Absolute stability is ±0.01°C over the complete temperature range, and the Hydra 798 Temperature Bath can provide comparison accuracies of ±0.0002°C with an appropriate measurement system. These baths are also suitable for creating and maintaining ITS-90 Fixed-Point Cells, both common large cells and Slim cells.

• Parallel Tube Action - Liquid flows up the
  rear volume of the bath and down the
  working volume. This action creates very 
  small vertical and axial gradients. 
  Enabling the smallest overall uncertainties

• Stability - Better than ±0.01°C over the
  complete temperature range

• Calibration Depth — Double the depth of some
  baths, the Hydra Range has up to 300mm
  depth of immersion

• Circular Design - The circular design
  eliminates ‘cold corners’ in tank-shaped baths

• Fast Cool Down - Goes from ambient
  to -80°C in 150 min

• Heating - All heating is outside the container. By using a large 
  area nickel foil heater the complete bath wall is heated uniformly

• Cooling - The cooling is built-in and also surrounds the calibration volume creating a low temperature ambient in which the heater can function efficiently

• Wider Temperature Range - A unique system removes the coolant 
  from around the calibration volume above ambient and lets the bath
  heat up to 125°C (121°C is a key sterilization temperature)

• Commercial Grade Chillers - The chillers are 1/3 horse power commercial grade units (not cheaper domestic grade as used by some manufacturers)

The 798 Range, with their depth of 300mm, satisfies the needs of professional engineers who understand the need for sufficient immersion of at least 270mm as recommended in Supplementary Information to the International Temperature Scale of 1990 (ITS-90).

The baths have a 150mm diameter offering one of the largest calibration volumes available. 
The parallel tube concept where liquid flows up the rear volume and down the calibration volume virtually eliminates vertical and axial gradients.