JPH01112685A - Dewing prevention device - Google Patents

Abstract

PURPOSE:To surely prevent dewing by providing a humidity detecting device detecting the relative temperature, judging the estimated dewing time based on the output humidity change, and controlling a heater so as to increase the temperature in an equipment to be controlled to the preset designed temperature at that time. CONSTITUTION:A humidity detector 2 and a temperature detector 3 are provided in an equipment to be controlled 1, the outputs are guided to a control judging unit 4, a control switch 5 is opened or closed according to the judgment result to operate a heater 6. The time C when the relative humidity becomes 100% is estimated by a control judging unit 4 based on the humidity at the optional time A and the humidity at the time B after the optional time (t), the lead time necessary to operate the heater 6 is judged by the control judging unit 4 so that the preset temperature rise can be obtained at this time C, the heater 6 is controlled with the lead time so that the preset temperature rise can be obtained at this time C, thereby no dewing invariably occurs in the equipment to be controlled.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a control box, an operation box, a terminal box, and a dew condensation prevention device for an electrical equipment main body.

(Prior Art) Conventionally, as a heater control for the purpose of preventing dew condensation in electrical equipment, temperature control has been adopted in which the heater is operated when the temperature falls below a certain temperature.

However, even if the temperature is kept high to a certain extent,
Because high relative humidity can cause dew condensation, humidity conditions have been added to control temperature and humidity. However, in this case as well, depending on the internal volume of the controlled device and the capacity of the heater, it takes time to obtain the specified temperature rise.
This time delay may cause condensation.

(Problems to be Solved by the Invention) - According to the conventional technology, it takes time to obtain a predetermined temperature rise, and this time delay often causes dew condensation. Furthermore, if a large-capacity heater is used to shorten this time delay, or if it is controlled to turn on and off frequently, the device becomes bulky, which is not desirable either economically or as a control means. The object of the present invention is to provide an economical dew condensation prevention device that can reliably prevent condensation inside a controlled device without any time delay.

[Development of invention]

(Means for solving the problem) The present invention uses a control determination unit to determine time C at which the relative humidity becomes 100% based on the humidity at an arbitrary time A and the humidity at time B after an arbitrary time. At time C, the control determining section determines the lead time required to operate the heater so as to obtain a predetermined temperature rise, and closes the control switch.

(Function) In this way, the time C at which the relative humidity becomes 100% is estimated, and at that time C, the heater is controlled with a lead time so that the predetermined temperature rise is obtained. There should always be no condensation inside the container.

(Example) The present invention will be described in detail below with reference to FIGS. 1 and 2. A humidity detector 2 and a temperature detector 3 are provided inside the controlled device 1, and the output thereof is led to a control determination section 4, and the heater 6 is operated by opening and closing the control switch 5 according to the determination result. .

That is, from the humidity at an arbitrary time A and the humidity at a time B after an arbitrary time, the control determination unit 4 estimates a time C at which the relative humidity becomes 100%. The control determination unit 4 determines the lead time required to operate the heater 6 so as to obtain a temperature rise of
Close the circuit.

In this way, the time C when the relative humidity becomes 100 is estimated, and at that time C, the heater 6 is controlled with a lead time so that a predetermined temperature rise is obtained, so that the inside of the controlled device is Always free of condensation.

In FIG. 1, the effect is the same whether the number of heaters 6 is one or more. The same applies even if there are a plurality of control switches 5.

FIG. 3 shows an embodiment in which a temperature detection device 7 is provided outside the controlled device 1 to measure the difference between the internal temperature of the controlled device 1 and a predetermined temperature difference, for example, 100%, with respect to the outside temperature. %
This is an example in which it is possible to control by providing a temperature difference of 2° C. that can bring the relative humidity of the atmosphere to 90%.

FIG. 4 shows an embodiment in which there are a plurality of controlled devices 1 and these are collectively controlled.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to obtain a dew condensation prevention device that can control the temperature rise inside a controlled device without time delay and can reliably prevent condensation without using a large-capacity heater. can.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing an embodiment of the dew condensation prevention device of the present invention, Fig. 2 is a characteristic diagram showing the relationship between relative humidity and time to explain the dew condensation prevention of the present invention, and Figs. The figure is a block diagram showing another embodiment of the dew condensation prevention device of the present invention. 1... Controlled device 2... Humidity detection device 3...
・Temperature detection device 4...Control determination unit 5...Control switch 6...Heater agent Patent attorney Noriyuki Ken Chika Kenichi Daishimaru 2%3 4 Figure 1 Figure 2 Figure 3 Figure 4

Claims (3)

[Claims] (1) Equipped with a humidity detection device that detects relative humidity, determines the estimated time of condensation based on the humidity change in the output, and at the estimated time of dew condensation, raises the inside of the controlled device to a predetermined design temperature rise value. A dew condensation prevention device characterized by controlling a heater. (2) A patent claim comprising a humidity detecting device and a temperature detecting device, determining a change tendency of relative humidity based on changes in humidity and temperature, determining an estimated time of condensation based on this, and controlling a heater. The condensation prevention device according to item 1. (3) Equipped with a humidity detection device and a temperature detection device that detect the relative humidity inside the controlled device, and a temperature detection device that detects the temperature outside the controlled device, and calculates the estimated time of condensation based on the output of each. It is determined that the temperature difference between the outside and inside of the controlled device is
2. The dew condensation prevention device according to claim 1, wherein the heater is controlled so that the temperature inside is 2° C. or more higher.