JPH02301983A - Heater device and power source closing method - Google Patents

Abstract

PURPOSE:To reduce consumed electric power at the time of starting current application by providing such a constitution as dividing a PTC heater into a plurality of units and varying the time of power input to each unit to successively start current application to each unit. CONSTITUTION:A PTC heater is divided into six units, and each unit 201, 202, 203, 204, 205, 206 is connected in parallel to a power source. A push button switch 231 for starting the closing magnet 221 of the first unit simultaneously starts the timer control devices 232, 233 of the second and third units, and the time counting is started with the time of starting the current application to the first unit 201 as a standard point. After 3 minutes from the start of current application to the first unit, the timer control device 232 is operated to start current application to the second unit. Similarly, current applications to the third to sixth units are successively started at intervals of 3 minutes.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a PTC heater, that is, a heater having a positive temperature coefficient of resistance, and relates to an electric low-mounting device and a method for turning on power to the heater device as the temperature increases. For example, heating relatively large areas such as roof snow melting equipment, floor heating equipment, road heating, etc.
It is particularly useful as an electric heater for heating.

(Prior Art) In conventional roof snow melting equipment, floor heating equipment, road heating, etc., as shown in FIG.
When laying the required length by bending it into a sagging shape, etc., and heating it, close the cloth 3 and connect the entire length of the heating element 1 to the power source 4, and apply current to the entire length of the heating element at the same time. It was designed to stream. Even if the heating element is divided into multiple units due to the installation of the heating element, all of the units connected in series or parallel to the power source will be powered on at the same time and will not be energized at the same time. It was configured to be started.

(Problem to be solved by the invention) The electrical resistance of a PTC heater increases significantly as the temperature rises, so a large current flows when the PTC heater starts to be energized, but after the energization starts, the temperature of the heater rises due to Joule heat. , the current carrying current decreases rapidly as the electrical resistance increases. In other words, when it comes to PTC heaters, it's a good idea! , At the start, a large current flows and the power consumption is large, but during steady energization, the current flowing, and hence the power consumption, decreases significantly, and there is a significant difference in I-i power consumption between the start of energization and the steady energization. This difference in power consumption becomes particularly large when the ambient temperature is low and the temperature of the heater at the start of energization is low, such as when using a roof snow melting device or the like.

Due to this large difference in power consumption between the start of power supply and steady power supply, conventional roof snow melting equipment, floor heating equipment,
In road heating, etc., the capacity of power equipment has to be significantly larger than that required for steady energization, which has the disadvantage of increasing equipment costs for power equipment. . In addition, the contracted power is significantly larger than the power required during steady energization, resulting in an inconvenience that the contracted electricity bill becomes high.

The present invention aims to solve such difficulties in conventional PTC heater devices by reducing the power consumption of the PTC heater device at the time of starting energization by a simple means. The aim is to reduce the difference in power consumption, thereby reducing equipment costs for power supply equipment and contract electricity charges.

(Means for Solving the Problems) In order to achieve the above object, 1. In the present invention, PTC
Divide the heater into multiple units, connect each unit to a power source so that current can flow individually, and turn on power to each unit at different times. = −/ Start applying current to the points in sequence.

To explain this in more detail, for example, 3 minutes after the power is turned on to the first unit, that is, after the temperature of the PTC heater of the first unit has risen and the current flowing through the unit has decreased sufficiently, Power is then applied to the second unit. For example, 3 minutes after the second unit is powered on, the second unit's PTC
After the temperature of the heater rises and the current flowing through the unit is sufficiently reduced, power is turned on to the next third unit. Thereafter, power is sequentially applied to each of the other units in the same manner.

In this way, by changing the timing for turning on power to each unit and starting energizing each unit in sequence, the maximum value of the energized current and, therefore, the power consumption can be adjusted as shown in the example below. The maximum value of can be significantly reduced.

The number of divided units and the time interval between turning on the power to each unit are determined by the ambient conditions surrounding the PTC heater, in the case of a snow melting device on a roof, the air temperature, wind speed, snow temperature and amount, and the state of contact between the snow and the PTC heater. , it is necessary to make an appropriate selection depending on the installation location of the PTC heater, etc., but if the ambient conditions surrounding the PTC heater are severe and the temperature rise of the heater is slow, it is sufficient to lengthen the time interval between power-on, and in the opposite case, What is necessary is to shorten the time interval between power-on. P.T.
The number of unit divisions of the C heater also changes depending on the surrounding conditions, and in places with severe conditions, the number of divisions can be increased, and in the opposite place, the number of divisions can be decreased. Usually, the number of divided units is selected to be 2 to 10, more preferably 4 to 6, and the power-on time interval is selected to be in the range of 0.5 to 30 minutes.

As mentioned above, when to start energizing the next unit,
If the time is determined based on time, the power may be turned on manually, or a timer may be used to control the closing of the switch that connects the next unit to the power source.

The timing for turning on the power to the next unit can also be controlled by detecting the temperature of the PTC heater of the previous unit or the magnitude of the current flowing through it.

In other words, a temperature sensor is attached to the PTC heater of each unit, and the temperature sensor detects when the temperature of the PTC heater of the unit whose power is turned on and electricity has started reaches a predetermined temperature (for example, selected in the range of 10 to 30 degrees Celsius). When this happens, turn on the power to the next unit. Or PTC of each unit
Attach a current sensor to the heater, turn on the power, and make sure that the energizing current of the PTC heater of the unit that starts energizing reaches a predetermined current value (for example, choose a current value in the range of 90 to 60% of the current value when energizing starts). When the current sensor detects that the current has decreased, it turns on the power to the next unit and starts energizing it.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

(First Example) This example is aimed at a roof snow melting device, and is shown in Figure 2.
201, 202, 203, 204, 205 and 206 are PTC heater units installed on the roof (not shown) and connected in parallel to the power supply. In the figure, in order to simplify the drawing, only the first to third units are shown in detail, and the details of the fourth to sixth units are omitted. 211.212.213 are the first unit 201.213, respectively. 2nd unit t) 202, 3rd unit 20
3 to a power supply 24 with a voltage of 100V, respectively.

The opening is closed by the operation of magnets 221, 222 and 223. 231 is a push-button switch that activates the closing magnet 221 of the first unit, but this also activates the timer control devices 232 and 233 of the second and third units, and the first unit 201 is energized. Start counting time using the start time as a reference point. Three minutes after the button switch 231 is pressed and the switch 211 is closed to start energizing the first unit, the timer control device 232 is activated to activate the magnet 222, close the switch 212, and turn on the second unit. Power supply starts. Furthermore, 6 minutes after energization of the first unit (i.e., the second
3 minutes after the unit is energized), the timer control device 233 is activated and the magnet 223 is activated.
The switch 213 is closed and power supply to the @3 unit is started. Thereafter, energization is sequentially started to the fourth, fifth, and sixth units at a time interval of 3 minutes in the same manner. Each unit PT
A heating element functioning as a C heater is arranged bent in a blind shape as shown in the figure, and the heating element has a conductor cross-sectional area AW.
G18 (0,82 simple 2) parallel 2-core tinned copper N, irradiated cross-linked conductive polymer (heater element) arranged between the poles, thermoplastic inner jacket metal braided around the outer periphery, thermoplastic It is equipped with a plastic elastomer outer jacket and has an output of 20 W per unit length (1 m) at an ambient temperature of 0° C. (when one source voltage is 100 V). This heating element is bent and laid in a slanted manner so that it is disposed about 10 m per unit area, that is, per unit area of the roof.

Therefore, the power consumption per unit area of the unit is 1 to 200 W when the ambient temperature is 0° C. (when the power supply voltage is 100 V).

In this embodiment, the PTC heater is divided into 6 units, and each unit is turned on and energized in sequence at a time interval of 3 minutes. That is, the power supply room fifL becomes maximum. Calculating from the experimental results, this maximum current is only 58% of the total current when power is turned on to six units at the same time and power supply starts, and the effect of reducing the maximum current by the present invention is extremely remarkable. In addition, in this example, the ratio of the total current (maximum current) when power is started to the sixth unit and the total current during steady power supply is 118 times, whereas when power is supplied to all six units at the same time. The ratio of the total current when turned on and the total current during steady energization reaches about twice.

In this example, if the time interval for starting energization to each unit is shortened to 2 minutes, the total current (maximum current) when power is applied to the 6th unit is 125% of the total current during steady energization.
This is doubled and becomes 63% of the total current when all six units start energizing at the same time. On the other hand, even if the time to start energizing each unit was extended to 4 minutes or more, there was not much difference compared to the case where the time interval was 3 minutes.

These experiments were carried out at a temperature of -5 to -1℃ and a wind speed of 0 to 4m.
/second under conditions of 30 cm of snow.

(Second example) The first advantage is that the PTC heater is divided into four units.
This is different from the example. When the time interval between the start of energization to each unit was set to 3 minutes, the total current when energization started to the 4th unit was 132 times the total current during steady energization, and energization started to be applied to all 4 units at the same time. 66 of the total current when
%.

(Third Embodiment) The object of this embodiment is a floor heating system, in which a PTC heater is divided into 422 parts. Unlike the first and second embodiments, the timing to start energizing the next unit was controlled based on the temperature detected by a temperature sensor attached to the PTC heater of each unit. In this embodiment, this control is configured such that when the Vi temperature sensor detects a predetermined temperature of 30°C, the sensor issues a signal to the control device that activates the magnet that closes the sui-sochi of the next unit. but,
Alternatively, the temperature signal detected by the temperature sensor may be sent to the control device, and the magnet may be activated when the control device detects a predetermined temperature.

In the case of this example as well, the maximum current occurs when the 4th unit starts to be energized, but the value of this 711 current is 1.27 times the total current during steady energization, and all 4 units are energized at the same time. The total current when I started was 79.

Note that in the experiment in this example, electricity supply was started when the room temperature was 10° C. (the floor surface temperature was also the same).

(Effects) As is clear from the description of the above embodiments, according to the present invention, the current at the start of energization of the PTC heater device, and therefore the power consumption, can be significantly reduced, and the difference from the power consumption during steady energization can be significantly reduced. . Therefore, the capacity of power supply equipment can be reduced, equipment costs can be reduced, and contract electricity charges can also be reduced.

In addition, when changing the power supply voltage from 100V to 200V,
This effect becomes even more pronounced.

[Brief explanation of drawings]

Figure 1 is an explanatory diagram of a conventional PTC heater device, and Figure 2
1 is an explanatory diagram of a PTC heater device (roof snow melting device) according to the present invention. In Figure 1, 1: heating area, 2: heating element that functions as a PTC heater, 3: switch, 4: power supply In diagram 2, 201.202.203.204.205 and 206:
PTC heater units 211, 212 and 213:
Switch, 221.222 and 223: magnet), 2
31: Push-button switch, 232 and 233: Timer control device 24° power supply Although Figures 1 and 2 are diagrams of linear heating elements, the same applies to sheet heating elements.

Claims (8)

[Claims] (1) A power-on method for a heater device characterized by dividing the PTC heater into multiple units, changing the power-on timing for each unit, and sequentially turning on the power to each unit. (2) A heater device characterized in that the PTC heater is divided into a plurality of units and is equipped with a power-on device that sequentially turns on the power to each unit with different power-on times for each unit. (3) A method for powering on a heater device according to claim 1, characterized in that the power to the next unit is turned on after a predetermined period of time has elapsed since the power was turned on to the unit. (4) The heater device according to claim 2, further comprising a timer device that controls when the unit is powered on. (5) A method for powering on a heater device according to claim 1, characterized in that when the temperature of the unit to which power is turned on rises above a predetermined temperature, the power to the next unit is turned on. (6) Each unit is provided with a temperature sensor that detects the temperature of the unit, and a control means that controls when to turn on the power to the next unit based on the temperature detection signal of the temperature sensor, and the temperature is detected by the sensor. 3. The heater device according to claim 2, wherein when the temperature of the heated unit reaches a predetermined temperature, the power of the next unit is turned on. (7) The method for powering on a heater device according to claim 1, wherein the power to the next unit is turned on when the current flowing through the unit that has been powered on falls below a predetermined current flowing current. (8) An energizing current measuring means provided for each unit and measuring the magnitude of the energizing current of the unit, and a control means controlling the timing of powering on the next unit based on the current value detection signal of the energizing current measuring means. The heater device according to claim 2, wherein the heater device is configured such that when the current flowing through the unit detected by the current measuring means falls below a predetermined value, the power to the next unit is turned on.