Digital thermometers are very convenient to use. First of all, it is important to note that they have a low percentage of error. Many models are able to determine the humidity in the room.
Remote sensor devices are most suitable for laboratory research. Models differ in sensitivity and type of sensor. In order to get a grip on this issue, you should consider the standard scheme of a digital thermometer.
Device diagram
A conventional thermometer includes a multi-channel type sensor, as well as a set of resistors. The signal is directly displayed on the display using a small chip. Capacitors are installed on it. To increase the sensitivity of the device, different types of thyristors are used. The capacity of the modification depends on the capacitance of the transistors.
How to make a model?
Making a digital thermometer with your own hands is quite simple. The sensor itself needs to be selected with a stylus type. Modifications with suction cups are difficult to do. Also, a thyristor unit is required for operation. Next, to make a digital thermometer with your own hands, a compact sensor is taken. The chip is selected series PP20. To increase sensitivity, various elements are used. In this case, an amplifier can be used. As a rule, impulse modifications are presented on the market.
They are quite expensive, but they can work a lot. Capacitors are used to carry out the calibration process. On average, the cell capacitance should not exceed 3.5 pF. To increase the threshold of permissible temperature, resistors with different conductivity are used. In order to connect the sensor, you need a two-wire cable. It connects to the output contacts of the microcircuit using a conventional soldering iron.
DC-1 Reviews
This digital thermometer with a remote sensor is very easy to use. First of all, it is important to mention a wide temperature range. If necessary, the device is able to accurately determine the level of moisture. The interface in this case is used by the PC series. A jack for connecting a USB cable is provided by the manufacturer. The accuracy of the thermostat measurement is not more than 1.3%.
The calibration speed of the equipment is quite high. The sensor in the device is a probe type. For laboratory research, the model fits well. The protection system is provided by the IP31 series. The standard device kit includes a battery sensor and a direct digital thermometer. The instructions are also attached by the manufacturer. This model is on the market in the region of 540 rubles.
Description of DC-2 Thermometers
This is a fairly simple and convenient digital thermometer. Its circuit includes field capacitors and a pulse transistor. For domestic use, the model fits perfectly. The moisture level in this case cannot be measured. If you believe the customers, the equipment turns on pretty quickly. Batteries come with a small capacity as standard. The through resistance of the presented modification is at the level of 4.5 Ohms. The direct minimum allowable temperature of the sensor is -70 degrees. The interface is simple and intuitive. The function of storing the value in the thermometer is absent. The sensor is used as a probe type.
DC-5 device
This digital remote thermometer has a high threshold for permissible temperature. The model is quite expensive, but it has a lot of advantages. First of all, it is important to mention the low percentage of error. The sensor is a multi-channel type. Calibration speed is high.
The interface itself is applied by the PC series. The protection system in the equipment is installed IP32. A moisture meter function is provided for the device. The device is ideal for field research. The through resistance of this modification does not exceed 6 ohms. The presented thermometer is sold at a price of 2100 rubles.
Digital 202 Thermometers
It is a compact and convenient digital thermometer. Its circuit includes capacitive capacitors and a sensitive sensor. Many people buy the appliance for domestic use. If desired, he is able to show the level of moisture in the apartment. The calibration speed of the model is very low. It is also important to note that the error level is as much as 2.5%. The end-to-end resistance is at 4 ohms. The protection system is used by IP 33. The user is able to purchase a thermometer of the presented brand for only 600 rubles.
Digital 320 Reviews
The indicated digital thermometer with an external sensor is sold with a fairly high-quality sensor. Directly the sensor is installed multi-channel type. The average measurement time is 1.2 seconds. As a rule, the error rate does not exceed 0.8%. Most often, a model is acquired for laboratory research. However, it is important to note the low threshold temperature limit.
The calibration process in the device takes a lot of time. According to customers, the device starts with a slight delay. In total, the device uses two batteries. Enough of them for about three hours of work. The interface is provided by the manufacturer of the PC series. The USB port connector is located on the side panel. You can buy this thermometer for 1600 rubles.
Description of Digital 700 Thermometers
The indicated digital thermometer with a remote sensor is universal. In the apartment, he will help determine not only the exact temperature, but also the level of humidity. The sensor itself is used multi-channel type. The sensor is provided as a standard probe. The gain in this case cannot be adjusted. The control interface is provided by the PC series.
According to customers, the thermometer turns on very quickly. However, the time to obtain the result can be long. The sensitivity indicator of the presented model fluctuates around 4.5 mV. The through resistance of the modification is at 5 ohms. The price of the presented thermometer fluctuates around 1300 rubles.
Digi Sense Device
This digital thermometer is mostly positive for customer reviews. Many owners praise the device for compactness. If necessary, he is able to determine the exact level of humidity in the room. The interface is used as standard PC series. If necessary, the user can change the sensitivity parameter. The maximum allowable temperature of the equipment is 200 degrees. In total, the model uses one sensor.
In this case, the resistors are installed pulse type. If you believe the experts, the batteries last for about three hours of operation of the equipment. The capacitors of the thermometer are used capacitive type. Given this, the equipment has a high accuracy of temperature measurement. The error rate in this case is at the level of 2.1%. You can buy the presented thermometer for only 800 rubles.
Shenzhen K55 Thermometers
The specified multifunctional digital thermometer with a remote sensor is designed to work in laboratory conditions. In this case, the sensor is connected via a three-wire cable. The equipment is powered through conventional lithium batteries. Battery life - no more than three hours. The microcircuit in this case is provided for a switched type.
There is a USB connector on the side of the equipment. The function of storing the results of the model is not provided. It is also important to note that the model turns on with a low delay. The through resistance index does not exceed 5? 4 Ohms. The presented digital thermometer with a sensor is sold at a price of 800 rubles.
Reviews about Shenzhen K35
Many buyers respond positively to this thermometer. In particular, it is praised for its compactness. He has weak batteries and lasts for about an hour of battery life. However, it is important to note that the model is able to determine the level of humidity in the room. The interface itself is provided by the PC series. In this case, the values on the screen are clearly visible.
The transmitter at the thermometer is provided by the manufacturer for a multi-channel type. If necessary, the sensitivity of the device can be adjusted. The through resistance index is no more than 5.5 ohms. The minimum allowable temperature of the equipment is -60 degrees.
The signal transmission speed of the model is high. This was largely achieved through the use of high-quality resistors. The margin of error is not more than 2%. The minimum spread of resistance is at 1%. Capacitors in the device are single-shot type. Presented is a digital thermometer with a sensor at a price of 1200 rubles.