A new family of low-cost dry block temperature calibration systems has been developed by Isotech, in collaboration with Eurotherm.
There are nine models in the Plus range, covering different temperature ranges from -55°C to 1200°C, temperature bath volumes and mechanical configurations. Each model is available in bench top or portable versions. Bench top (Basic) versions incorporate one temperature controller with a dual display for Set Temperature and Dry Block Temperature, while portable (Site) units additionally include a built-in digital indicator to which an external temperature sensor can be connected. This allows the probe under test to be related to appropriate standards.
The control and indication system for the Plus family was developed in conjunction with Eurotherm. During normal calibration routines, the unit under test may simply be compared to the displayed controller value, but for higher accuracy, the manufacturer recommends the use of an external probe connected to the additional indicator of the S model. This approach compensates for temperature gradient and loading errors to give higher accuracy.
All S types have a universal sensor input, allowing platinum resistance thermometers, thermocouples (K,N,R,S,L,B,PL2,T,J and E) along with linear process inputs (including 4-20mA current transmitters) to be displayed on the indicator. The indicator can be programmed with five calibration points to provide accurate digital probe matching. Both indicator and controller - based on a standard Eurotherm 2216 - are addressable over a serial communications link.
All Plus models include a PC interface and a software tool, Cal NotePad, designed for use with Windows.