The Fluke Calibration Tweener (formerly Hart Calibration) thermometer readouts consists of two models – the 1502A and 1504. No
other thermometer comes close to the performance and features of the Fluke Tweener thermometer readouts
for anywhere near the price.
The 1502A readout features accuracy up to ±0.006°C. In addition, it
reads 100-ohm, 25-ohm, and 10-ohm probes, has a resolution of 0.001°C across its entire range, and is
the smallest unit in its class. The 1502A readout also has an optional battery pack
for completely portable operation.
Each 1502A readout is programmable to match a probe’s constants for maximum
linearity and accuracy. All probe constants and coefficients are programmed through simple, front-panel keystrokes.
Temperature is displayed in °C, °F, K, or resistance in ohms.
The 1502A readout accurately measures the resistance of the probe and then converts
the resistance to a temperature value using its built-in algorithms.
For convenience, the 1502A readout reads the common industrial grade IEC-751 or
“385” ALPHA RTD without any programming. Enter the actual R0 and ALPHA of the individual probe for increased
accuracy. For maximum accuracy, use the ITS-90 formulas. The 1502A readout accepts
the subranges 4 and 6 through 11.
ITS-90 formulas reside in the Tweener’s firmware. If your probe has been calibrated for any of the above subranges
of the ITS-90, you simply enter the coefficients directly into the 1502A readout.
Each thermometer comes complete with an RS-232 interface for automation of temperature data collection, calibrations,
or process control functions. An IEEE-488 interface is available as an option.
The 1502A readout is calibrated digitally using the front-panel buttons. You never have
to open the box to calibrate it. This calibration protocol further reduces the cost of the 1502A. It goes where you go
and works the way you want it to.
If you need more accuracy in a limited temperature range, the 1504 readout gives
it to you as a thermistor readout. Thermistors are less fragile than PRTs and less likely to be impacted by mechanical
shock. Thermistors are more sensitive to temperature, have faster response times, and come in many shapes for
different applications.
Typical accuracy of the 1504 is ±0.002°C with a resolution of
0.0001°C.
