Fluke 5020A user manual Unit of Temperature, Recording Measurements, Sensors, Sensor Accuracy

General Operation 4

Unit of Temperature

Unit of Temperature

The thermo-hygrometer is capable of displaying temperature in Celsius (C) or Fahrenheit

(F). The unit of temperature applies to temperature measurements on either channel that are displayed, recorded, or printed. Recorded data is viewed, printed, or written to a data card file with the currently set unit of temperature. The unit of temperature is set using the DISPLAY SETTING function in the DISPLAY menu (see Display Setting) or the SYSTEM SETTING function in the SYSTEM menu (see System Setting).

Recording Measurements

The thermo-hygrometer will automatically record measurements on enabled channels at the set period. Recording is enabled using the RECORD SETTING function in the DATA RECORD sub-menu in the DATA menu (see Record Setting). The record period is also set with this function.

Sensors

The standard-accuracy sensor and high-accuracy sensor are used to measure temperature and relative humidity. The sensors attach to the thermo-hygrometer by plugging into the top or side panel of the instrument.

The sensor contains a memory device that stores information about the sensor and automatically transfers this data to the thermo-hygrometer when the sensor is attached. This ensures that the settings used to measure and calculate temperature and humidity always match the sensor being used.

Caution

Sensors are fragile devices that can be easily damaged by mechanical shock, overheating, and exposure to fluids or dust. Damage may not be visibly apparent but nevertheless can cause drift, instability, and loss of accuracy. Observe the following precautions:

•DO NOT allow sensors to be dropped, struck, or stressed.

•DO NOT overheat sensors beyond their recommended temperature range.

•DO NOT expose sensors to harmful vapors, fumes, dust, or condensation.

•DO NOT allow sensors to come into direct contact with any fluids.

Sensor Accuracy

To achieve full accuracy with the thermo-hygrometer sensors, a few precautions should be noted.

First, consider that the sensor actually measures its own temperature, not necessarily the temperature of the air around it. Ideally, the sensor's temperature will be the same as the air, but they might be different under less than ideal conditions.

One such condition is when there is a source of radiated heat that is "seen" by the sensor. Radiated heat tends to heat up the sensor higher than the air around it (try shining a flashlight on the sensor from some distance away). Some sources of radiated heat to avoid are incandescent lamps, space heaters, and other high-temperature devices. If such

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