Ultra Stable Standard Resistor Maintenance Baths

Mon 10.08.2026

Kambic OB-LTUS is an ultra-stable liquid bath designed for the maintenance and temperature stabilization of standard resistors used in calibration laboratories and national metrology institutes. With temperature stability of up to ±0.003 °C, uniformity better than ±0.007 °C, and a unique vertical flow design, it provides the ideal environment for high-accuracy resistance measurements, reducing uncertainty and ensuring long-term stability of reference standards.

Kambic OB-LTUS: Ultra-Stable Liquid Bath for Standard Resistors

Kambic OB-60/2 LTUS, OB-100/2 LTUS, and OB-110/2 LTUS are state-of-the-art liquid baths specifically designed for the long-term maintenance and temperature stabilization of precision standard resistors used in national metrology institutes, accredited calibration laboratories, and reference measurement facilities. With exceptional temperature stability and bath uniformity, they provide an ideal environment for achieving the highest accuracy in electrical measurements.

Key Benefits for Standard Resistor Calibration

• Temperature stability of up to ±0.003 °C at 23 °C, minimizing temperature-induced changes in resistor values.
• Outstanding temperature uniformity better than ±0.007 °C, ensuring identical conditions for all immersed standards. 
• Unique vertical fluid flow design throughout the working volume, eliminating temperature gradients and ensuring uniform heat distribution.
• 0.001 °C display and setpoint resolution for precise temperature control. 
• Operating temperature range from +5 °C to +60 °C, suitable for most resistance metrology applications.

Designed for Metrology Laboratories

The OB-LTUS series has been developed specifically for applications where the long-term stability of resistance standards is critical. Its double-cylinder construction combined with an optimized fluid circulation system provides exceptionally stable temperature conditions for 1 Ω, 10 Ω, 100 Ω, 1 kΩ, and other reference standard resistors. 

A transparent hinged cover with multiple feedthrough ports allows easy routing of measurement leads without significantly disturbing the bath environment. The robust AISI 304 stainless steel construction, high-performance thermal insulation, and four-sided service access ensure long service life and convenient operation. 

Advanced Control and Data Monitoring

The system features a sophisticated controller with a 7-inch capacitive touchscreen, Ethernet and USB connectivity, and the OB-Tool software package for temperature monitoring, data logging, and analysis on a PC.

Available Bath Volumes

Ideal for

• Electrical calibration laboratories
• National metrology institutes
• Long-term maintenance and stabilization of standard resistors
• High-accuracy DC resistance measurements with the lowest uncertainties
• Reference laboratories of instrument manufacturers

Kambic OB-LTUS represents one of the most accurate solutions available for the temperature stabilization of resistance standards, where every millikelvin directly impacts the final measurement uncertainty.