Overview
Hart’s Super-Thermometers, including the Model 1575A and Model 1590, are renowned for their precision and ease of use in metrology laboratories. The 1575A offers accuracy to 0.001 °C, while the 1590 provides even greater precision at 0.00025 °C (1 ppm). Both models are ideal for Standard Platinum Resistance Thermometer (SPRT) calibrations and are cost-effective alternatives to traditional resistance bridges.

Specifications and Features

• Model 1575A: Known for its user-friendly interface, high accuracy, and affordability. It features built-in software for direct temperature readings and automated ITS-90 constant calculations. It can store up to 16 probe characterizations.
• Model 1590: Offers all features of the 1575A with enhanced accuracy of 1 ppm and a tilting color screen. It is priced at less than half the cost of a resistance bridge.

Advantages Over Resistance Bridges
Resistance bridges are expensive and complex, with prices ranging from $30,000 to $50,000. Hart’s Super-Thermometers provide a simpler, more affordable solution with comparable accuracy, making them a preferred choice in many labs.

Accuracy and Calibration
The Super-Thermometers offer significantly lower error levels compared to typical benchtop thermometers. The 1575A achieves ±0.002 °C accuracy, while the 1590 achieves ±0.00025 °C. Both models come with accredited calibration.

Technical Specifications

• Accepts SPRTs and thermistors ranging from 0.25-ohm to 100-ohm.
• Features include automated data collection, dual-channel operation, and on-board resistors housed in a temperature-controlled oven.
• Supports ITS-90 and IPTS-68 temperature conversions, with automated calculation of constants.
• Graphing capabilities for real-time monitoring and data storage in ASCII format.

Additional Features
Hart’s patented DWF Connectors facilitate easy and secure connections. The Super-Thermometers also offer programmable current sources, integration time, and digital filtering to optimize performance.

Multiplexers
For expanded channel capacity, the 1575A can be paired with the Model 2575 multiplexer, and the 1590 with the Model 2590, allowing up to 50 channels. These multiplexers feature low thermal EMF relays and support true four-wire measurements.

Conclusion
Hart’s Super-Thermometers provide a cost-effective, accurate, and user-friendly alternative to traditional resistance bridges, making them an excellent choice for precision temperature measurement and calibration in metrology labs.