Comparison TFA 30.5038 vs La Crosse WT140

Types of measurements that can be made using a thermometer.

— Internal temperature. Measurements of indoor air temperature. Note that measurements of water and soil temperature in thermometers for the appropriate purpose (see above) are also considered internal.

— Outside temperature. Taking outdoor air temperature can be challenging due to the constant changes and various external factors like precipitation, wind, and dust. Using a thermometer designed specifically for outdoor conditions is crucial, as regular indoor thermometers may not withstand these elements. Some models come equipped with external sensors, including wireless options, to facilitate accurate outdoor temperature measurements.

— Humidity. Measuring relative air humidity is vital for assessing comfort and well-being, as it is a key factor alongside temperature. Dry air can make heat more tolerable, but both low and high humidity levels can be uncomfortable at room temperature. This function becomes crucial in maintaining a suitable microclimate, especially when there are small children in the house, as they require a specific and controlled environment for their well-being.

— Atmospheric pressure. Changes in atmospheric pressure not only affect how you feel, but also allow you to predict the weather with some degree of accuracy: for example, precipitation is us...ually associated with low pressure.

In some advanced models, other, more specific measurements may be provided — for example, an assessment of the level of carbon dioxide with a warning about the need for ventilation, or the calculation of the dew point (a complex indicator that also affects the comfort of staying indoors).

Total allowable measurement range. The minimum / maximum temperature that the thermometer is able to fix, as a rule, is also acceptable for using the device — with further cooling / heating, malfunctions are possible up to complete failure.

Low values of this parameter are crucial for outdoor dryer models. Additionally, the inherent "margin of safety" in measuring systems often results in finding sub-zero temperatures in purely indoor models. This feature can be practical, such as assessing conditions in an unheated room during winter.

Most contemporary household thermometers boast a maximum temperature range of 50 — 60 °C, sufficient for even relatively hot climates. However, there are less heat-resistant models with temperatures ranging from 30 — 40 °C. Thermometers designed for water applications have a lower maximum temperature, as it is not necessary for their intended use. Sauna thermometers typically exhibit the highest temperature resistance.

— Display backlight. The backlight feature enables reading the display in low light or darkness. Typically activated by pressing a button and deactivated upon release, this design minimizes energy consumption. However, some devices may keep the backlight on continuously for decorative purposes.

— Clock. Clocks that show the current time vary in dial type and functionality based on the thermometer type mentioned earlier. Electronic models use digital displays with added features, while mechanical thermometers typically feature traditional arrow dials. Some of these mechanical models even resemble watches with an integrated thermometer, emphasizing the thermometer aspect rather than the clock.

— Alarm clock. Possibility of giving a sound signal at a certain time set by the user. An alarm clock can be used not only for getting up in the morning, but also for any reminders associated with a specific time — for example, as an impromptu replacement for a kitchen timer. This feature, by definition, requires a clock (see above).

— Calendar. The presence of a calendar implies at least the display of the current date on the thermometer (day of the month, often the month, less often the year). In addition, electronic models may provide viewing the year by month. The calendar can be used not only by itself, but also fo...r other functions — for example, fixing min / max temperature moments (see above).

— Moon calendar. This function provides a display of the current phase of the moon, and in most cases also allows you to determine the days of new moons and full moons. Auspicious moments for many types of human activities (cosmetic procedures, treatment, gardening) are directly dependent on the phases of the moon. This feature assumes a regular calendar (see above). — Synchronization with smartphone. The ability to remotely connect to the device using a mobile phone (tablet) allows you to remotely monitor weather conditions and read all information from sensors.

— Batteries. Thermometers are powered by standard-sized replaceable cells, such as AA or button cells like CR2023 or LR44. This design enables them to operate independently of power outlets, requiring only fresh batteries, which can be easily replaced. While a drawback is the periodic need to purchase additional batteries, the low power consumption of thermometers ensures that even inexpensive batteries have a long lifespan. Additionally, some models offer versatility by supporting mains or solar power in addition to battery power.

— Network. Operating on a standard 230 V household outlet, this device benefits from a constant voltage, ensuring virtually unlimited operation without the need for battery changes or recharging. However, the reliance on a mains cable restricts mobility and usage possibilities, and for household thermometers, this option doesn't offer significant advantages over battery-powered alternatives. As a result, mains power is not widely adopted in this context.

— Solar battery. Powered by a photocell that generates energy from sunlight (or other bright light source), this thermometer theoretically achieves independence from both the grid and batteries. However, its effectiveness relies on light intensity; insufficient sunlight, like on cloudy days or during nighttime, can render the solar battery practically useless. To address this, backup power is necessary, often supplied by batteries. When specifications mention only a sola...r battery, it typically implies an integrated battery charged by the photocell, serving as backup power.

A kind of external sensor used by a household thermometer (see "Purpose") with the possibility of external measurements.

— Wired. Wired sensors are inexpensive and do not require their own power supply, because they receive energy through the wire. At the same time, they are less convenient to install than wireless ones, since laying wires can be quite a hassle (up to having to drill a wall or window frame). And the distance to which the sensor can be taken from the thermometer is limited by the length of the wire.

— Wireless. Radio-connected sensors do not require wiring and can operate at a much greater distance from the thermometer than wired ones. On the other hand, they are noticeably more expensive and use their own power sources (batteries or accumulators), which need to be monitored and changed/recharged in time.