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F250 Precision Thermometer
ASL F250 Precision Thermometer
High Accuracy, Dual Channel Temperature Measurement for Platinum Resistance Thermometers

Accuracy of <±0.005°C(<±0.01°C full range) This Product is Obsolete...CLICK HERE FOR SUGGESTED REPLACEMENT - MilliK

  • Selectable resolution of 0.001°C or 0.01°C
  • Dual channel inputs A, B or A-B
  • Direct readout in Ω, °C, °F or K
  • Up to 32 channels with SB250 switchbox
  • FREE System Calibration Click here for details
Base Price: $4,176.00

Product Code: F250

   Product Description

Precision Thermometer ASL F250

High-Accuracy Precision Thermometer for PRTs


High Accuracy, Dual Channel Temperature Measurement for Platinum Resistance Thermometers

ASL's F250 provides you with high accuracy, dual channel temperature measurement for Platinum Resistance Thermometers (PRT) and exploits the inherent advantages of AC bridge technology to maintain repeatable measurements of the highest precision. Front panel data entry allows you to enter probe calibration data, so that the thermometer resistance can accurately be converted to temperature in °C, °F or K. A comprehensive range of features and multi-channel capabilities make the F250 ideal for a wide range of simple or specialist applications. You can use it as a single probe laboratory instrument, a portable site standard or as a permanently wired multi-channel scanning system, especially when used in conjunction with the data acquisition software.

8 or 16 channel SB250 switchboxes may be added to channels A and B giving a maximum of 32 input channels, without affecting system accuracy. Switching between channels can be accomplished through the keypad or via the communications interface. You can choose to connect your probes to front or back panels on both F250 and switchboxes.

PC Software.
You can use the optional SOFT250 application to provide a virtual instrument display for remote control and temperature versus time graphing. SOFT250 calculates and Callender van Dusen coefficients and performs data acquisition with ASCII file format for easy export.

The internal reference resistor in the F250 is calibrated against internationally traceable standards. Any small differences between the measured values of the F250 and the true values, are then stored in the instruments non-volatile memory as a correction curve, thus ensuring the accuracy of all future measurements.

ASL thermometers are thermally cycled to ensure good stability and are supplied with a 4 point calibration certificate traceable to NPL. The user entered calibration data ensures the best possible conversion of resistance to temperature and is far superior to general purpose matching where only R and the alpha value are entered. System accuracy is thus traceable to International Standards without a specific "System calibration". However, a traceable system calibration, with both F250 and probes together, is offered by ASL as an option to provide you with an overall system uncertainty as low as ±0.01°C.

A True Pedigree.
National standards laboratories around the world require the best instrumentation for their work. The majority of these organizations use ASL's top of the range Model F18 to set the temperature standard in their country. These include 20 out of the 22 members of the international C.C.T. (Consultative Committee of Thermometry). The F250 uses the same AC measurement techniques to provide you unrivalled performance, convenience and flexibility.
F250 Datasheet F250 Manual