The ST4 thermometer.
Temperature taking requires more and more precise readings given today's complex systems. At the same time, technicians still want thermometers that are easy to use, so time at the jobsite is kept to a minimum. And they want units that are rugged enough to deal with constant use and transportation in the back of a service van.

Brea, Calif.-based Fieldpiece says it has come up with such a product with its ST4 dual digital thermometer. "This product was built from the ground up for the HVACR field service technician," said Fieldpiece's Rey Harju.

The product was designed to provide temperature measurements using any K-type thermocouple. The units come with two bead-style K-type thermocouples for measurements of two temperatures in different locations at the same time (T1, T2).

The unit can display the real-time difference between the two thermocouple readings and display that (T1-T2), Harju said.

Furthermore, the tool was designed to be used while it is inside the carrying case. A magnet allows the technician to hang it. The front of the case is clear so the technician can press the buttons and read the display.

The new model includes what the company calls "wrap tab" thermocouples. "The wrap tab enables storage of the thermocouple wires and helps ensure that the wire is not constantly bending in the same place, thus extending the life of the thermocouples in the hands of the technician," said Harju.

Two hook-and-eye fastening strips are included for attaching the thermocouples to a pipe. The company said the standard thermocouples go up to 400 degrees F. With optional thermocouples, the meter can measure up to 2,000 degrees. The unit has LEDs to tell the technician if the thermocouple is not properly connected or if it has a broken wire.

A min/max function is included for recording the lowest and highest temperatures. The user can choose either Fahrenheit or Celsius and 1 degree or 0.1 degree resolution.

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Publication date: 06/07/2004