JPS5926771Y2 - Power switching device - Google Patents

Description

[Detailed description of the invention] This invention ld1 Emergency electricity: This invention relates to a power source switching device between a main power source and a standby power source, which also uses the characteristics of a light emitting diode to display the status of circuit operation, mainly in an emergency broadcast device. It is.

Emergency broadcasting equipment, etc.'1 In addition to using DC power obtained from a commercial AC power source as the main power source, it must also have a built-in backup power source such as a rechargeable storage battery for use in the event of a power outage. The power supply is switched to backup power supply during the power outage, and the main power supply is restored in the same way when the power outage ends.

When switching the power supply, the main power supply must be switched from the main power supply to the backup power supply, or from the backup power supply to the main power supply, without other equipment such as relays in the equipment erroneously operating due to voltage changes due to a power outage. According to laws and regulations, emergency broadcasting equipment and the like are required to be highly reliable and free from malfunctions.

The present invention was developed in view of the above points, and it connects a light emitting diode and a power supply switching relay in series to the main power supply, and switches between the main power supply and the standby power supply according to the voltage change of the main power supply. It is an object of the present invention to provide a power supply switching device that prevents malfunctions of other equipment due to its reliability and can also display the status by lighting the power switching device, thereby solving the above-mentioned drawbacks of the conventional power supply switching device.

The feature is that, due to the characteristics of the light emitting diode, when the power supply switching relay is switched due to a voltage drop in the main power source, the load relay is in a voltage state higher than the open circuit voltage; When the power supply switching relay is switched, the load relay is in a voltage state higher than the impressed voltage.

The configuration of the present invention will be described below with reference to the drawings in accordance with embodiments.

As shown in FIG. 1, in a power supply switching device 1, a main power supply 2, a light emitting diode 3, and a power supply switching relay 4 are connected in series in this order, and the light emitting diode 3 is read directly in the forward direction.
The main power source 2 is connected to one side of the switching contact 5 of the power source switching relay 4, and the backup power source 6 is connected to the other side, and switching is performed according to voltage changes of the main power source 2.

Normally, the power supply switching relay 4 is in an operating state, and the switching contact 5 is electrically connected to the main power source 2. During a power outage, the power switching relay 4 is in a reset state, and the switching contact 5 is electrically connected to the reserve power source 6. .

The main power source 2 is provided with an AC/DC converter and transformer circuit, and is connected to a backup power source 6 to charge a storage battery.

Following the switching contact 5, a self-holding load relay 8, 9 is connected to select and set, for example, the broadcast floor number via a -simultaneous recovery button 7.
is provided.

The load relay 8.9'j: its own contacts 10, 11 and setting buttons 12, 13 are connected in parallel, and when the setting button 12, 13 is operated, it is activated, and its contacts 10, 11 are conductive. - Press the recovery button 7 to return to normal operation, and contacts io and ii are opened.

To explain the switching action, when a power supply with a voltage of 20V is used, the general 20V relay used as the power supply switching relay 4 and the load relays 8 and 9 increases the voltage applied to the coil from zero. The voltage at the time of operation is about 14 to 16 V, and the open-circuit voltage when the voltage is reduced from the operating state to return to normal is about 6 to 8 V.

On the other hand, due to the characteristics of the light emitting diode 3 connected in series to the power supply switching relay 4, when the applied voltage increases from zero (1, the relays 4, 8
．． Approximately 18V higher than the emotional voltage of 9, the barley, which had been in an open (non-conducting) state, suddenly becomes active (conductive) and lights up, and conversely, when the voltage drops from the operating state, ,
At about 10 V, which is higher than the open circuit voltage of the relays 4.8 and 9, the operating state suddenly becomes open and the light goes out.

Therefore, as shown in FIG. 2, to explain the case where the main power supply 2 has a power outage from point A to point B, first, in the normal state before point A (the d1 power supply switching relay 4 is in the operating state, The switching contact 5 is connected to the main power source 2, and the light emitting diode 3
is lit.

Next, when a power outage occurs at point A, the voltage of the main power source 2 gradually drops.

At point C, where the voltage drops to about 10V, the light emitting diode 3 opens and becomes non-conducting, and the voltage applied to the power switching relay 4 becomes lower than the open voltage, the power switching relay 4 returns to its normal state, and the switching contact 5 closes. The power is switched to the backup power source 6, and the light emitting diode 3 is turned off.

At this time, the voltage applied to the load relays 8 and 9: dl does not drop below its open circuit voltage (approximately 6 to 8 V), and only the power source is switched while the operating state is maintained.

Subsequently, when the power outage ends at point B, the voltage of the main power supply 2 gradually increases, and at point D, when it reaches about 18V, the light emitting diode 3 becomes conductive and lights up, and the power supply switching relay 4
operates and the switching contact 5 is switched to the main power source 2.

At this time, since the voltage applied to the load relays 8 and 9 is higher than the sensing voltage (approximately 14 to 16 V), only the power source is switched while the operating state is maintained.

According to the power switching device of the present invention as described above, the main power source, the light emitting diode, and the power switching relay are connected in series in this order, and the light emitting diodes are connected in the forward direction, and the main power source is switched by using the characteristics of the light emitting diode. In order to switch between the main power source and the standby power source in response to voltage changes, it is possible to prevent malfunction by switching the power source with voltage changes that do not activate the plurality of load relays connected to the power source switching relay. .

Furthermore, due to the high reliability of the light emitting diode, there is no failure, making it ideal for emergency broadcasting equipment.

Furthermore, the operating status is displayed by turning on and off the light emitting diode, and it is easy to check whether the operation is being performed normally, which is useful for finding failures, and the high reliability mentioned above. Together with this, it has some practical advantages.

[Brief explanation of the drawing]

The drawings illustrate an embodiment of the present invention, and FIG. 1 is a basic circuit diagram, and FIG. 2 is a graph showing voltage changes during switching. DESCRIPTION OF SYMBOLS 1... Power supply switching device, 2... Main power supply, 3... Light emitting diode, 4... Power supply switching relay, 5... Switching contact, 6... Backup power supply, 8, 9...・Load relay.

Claims (1)

[Scope of utility model registration request] A main power source, a light emitting diode, and a power switching relay are connected in series in this order, and the light emitting diode is connected in a forward direction, and the main power source is connected to one of the switching contacts of the power switching relay connected to a plurality of load relays. , a backup power source is connected to each of the terminals, and the negative □ relay is in a voltage state higher than the open circuit voltage when switching the power supply switching relay due to a voltage drop in the main power source, and the power source is connected to the power source due to a voltage increase in the main power source. A power supply switching device characterized in that a switching relay is in a voltage state higher than a moving voltage when switching.