JPS5911217B2 - Remote control method of power supply - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for remotely controlling the power on/off of a terminal device of a computer system from the main device side, and enables accurate remote control using optical signals via an optical fiber cable used for information transmission. It is something to do.

5 In a computer system, when connecting terminal devices using optical fiber cables to form a network system, each terminal device is not necessarily installed in the same location as the main device, and may be installed in a different building. It's coming.

In such cases, in order to remotely control the power on/off of the terminal device from the main unit, a method is adopted in which a power control line is laid in parallel with the optical fiber cable and the operation signal is transmitted in the form of an electrical signal. It was getting worse. As a result, there are problems such as malfunctions caused by external noise such as lightning, and a voltage drop of 15% due to the transmission cable. Attempts are being made to make it compatible with operations. This figure shows a computer network system, where a is the main unit, b,...bn are terminal devices, and each is connected via an optical fiber cable c... has been done. As shown in the terminal device bl, the terminal device is equipped with an optical repeater d, and each terminal device and the main device are connected by an optical fiber cable 25 via the optical repeater d. has been done. The optical repeater d and the power supply unit e of the terminal device are connected by a conductor f. All of the other terminal devices have such a configuration, and the attenuation of the optical signal in the optical fiber cable when transmitting the information signal is compensated for by the optical 30 repeater d in each terminal device.
Therefore, the optical repeater d in each terminal device is always powered on. Light is generated at the same time as the main unit a is powered on to operate the terminal devices, and is transmitted to each terminal device b, . . . , No. through an optical fiber cable c. This light is not modulated with the 35 information signal and does not contain any information. The optical repeater d is equipped with a photoelectric conversion device such as a photocoupler, and the optical signal transmitted from the optical fiber cable is photoelectrically converted and sent to the power supply unit e via a conductor f.

The power supply unit e is equipped with a switch means such as a relay, and the switch means is closed by a signal input from the conductor f, the power supply unit e is started, and the terminal device is powered on. When the power is turned on in this manner, the terminal device starts up, and information sent from the main device can be output, or information can be input from the terminal device to the main device.

In the main unit, when the power is cut off, no light is generated, so no light reaches the optical repeater d, and the power-on signal from the conductor f is also turned off. As a result, the switch means of power supply unit e is opened and the power supply unit is turned off.
The terminal device is powered off. Each terminal device is equipped with a remote/local selection switch, allowing each terminal device to freely select between remote operation and local operation.

If this selection switch is set to the local side, power on/off will be performed on each terminal device, but if set to the remote side, the terminal device with the remote side selected will be able to control the power supply of the main unit. The power is turned on and off according to the following. In the illustrated example, the network configuration is in a loop shape, but the present invention can also be applied to one in which terminal devices are connected radially around a main device. Also, two optical fiber cables are used, one of which is used as a backup. In this way, by using the optical fiber cable for turning on and off the power of the terminal device, there is no need to install a dedicated electric wire for power operation, which reduces costs and eliminates electrical induction disturbances caused by lightning, etc. .

However, the system is designed so that the power is turned on when light arrives from the optical fiber cable, and turned off when the light no longer comes, so if the light level drops or momentarily cuts out for some reason, it can cause errors. This has the drawback of sending a disconnection signal to the power supply unit e and cutting off the power, which destroys information exchanged between the main unit and the terminal device. The present invention prevents the power from being cut off due to malfunction in a system that utilizes optical fiber cables for information transmission and turns on and off power to terminal devices depending on the presence or absence of light coming from the optical fiber cables. The purpose is to To this end, in the system shown in FIG. 1, the present invention provides a logic section in each terminal device to determine a power cutoff signal, and also outputs a special cutoff signal from the main device to the optical fiber cable when the power is cut off. When a disconnection signal is input to the logic unit via the optical repeater, the logic unit identifies it and sends the disconnection signal to the switch means of the power supply unit, while in the power supply unit, the power is disconnected by the disconnection signal. After that, a system is adopted in which the power is prohibited from being turned on again even if a turn-on signal arrives for a predetermined period of time. FIG. 2 shows an embodiment of the system of the present invention, and the same parts as in the system of FIG. 1 are given the same reference numerals.

What is different from Fig. 1 is that in the terminal equipment b1...Bn, there is a logic section g between the optical repeater d and the power supply unit e.
The logic section is provided with a discriminating section for discriminating the disconnection signal. In the optical repeater d, the optical signal is once converted into an electrical signal by a photocoupler or other photoelectric conversion device, and this electrical signal is also input to the discrimination section of the logic section. The cutoff signal determined by the "quick cut" section is input to the switch means of the power supply unit e. On the other hand, the power-on signal is
Similar to FIG. 1, the signal photoelectrically converted by the optical repeater is used and directly input to the switching means of the power supply unit via the conductor f. This switch means is configured to close when a turn-on signal is input from the optical repeater d to turn on the power to the power supply unit, and open to turn off the power to the power supply unit when a cut-off signal is input from the logic section. There is. On the other hand, the optical signal for remotely controlling the power supply uses light that does not contain information signals, which is generated when the main unit is turned on, as in the case of Figure 1, as a power-on signal, and a disconnection signal. creates a special disconnection signal by encoding it, and continuously outputs it from main unit a for a certain period of time. Therefore, the light generated when the power is turned on in the main unit becomes a power-on signal, which is input to the power supply unit e via the optical repeater d, in the same way as in the case of Fig. 1, and is transmitted to the power supply unit e. start.

When the power is turned off, a special disconnection signal is output from the main unit to the optical fiber cable c, which is determined by the logic section via the optical repeater d, and a disconnection signal is input to the power supply unit. , the power is cut off. In this way, power disconnection? This is done by determining the disconnection signal of u in the logic section, so even if a drop in the level of the optical signal or a momentary interruption occurs, unlike the case in Figure 1, the power will be cut off by mistake and the information being processed will be lost. There is no risk of it being destroyed.

Further, since the disconnection signal is output continuously for a certain period of time, even if a drop in signal level or a momentary interruption occurs during transmission of the disconnection signal, the disconnection signal will be reliably transmitted and received. Furthermore, even if a special signal is used for the input signal, it is impossible to determine the input signal because the logic section is not powered on yet.
When the power is turned off, the disconnection signal can be determined using the logic section that is already in operation, so it is possible to use a special signal when the power is turned off. However, as shown in the time chart in Figure 4, the power to the main unit (B) is not necessarily cut off at the same time as the transmission of the disconnection signal (C) is completed, and the light serving as the ON signal is not always cut off. Even after completion of the process, light still reaches each terminal device from the main device.

Therefore, even after the terminal device is once disconnected, there is a risk that the terminal device will receive the input signal and be powered on again at the same time as the termination of the disconnection signal transmission. In order to eliminate such concerns, the present invention provides the power supply unit e with a re-turn-on prohibition circuit as shown in FIG.

In the illustrated example, relays Rl and R2 are provided, and contact R2 of relay R2 and closing switch S are connected in series with relay R.
Wl is connected. This closing switch SWl is a switch that is closed when a closing signal is input from the conductor f. On the other hand, disconnect switch SW is connected in series with relay R2.
2 are connected. This cutoff switch SW2 is a switch that is closed when a cutoff signal is input from the logic section g. A time constant circuit h consisting of a capacitor and a resistor is connected in parallel with relay R2. Relay R2
When is not energized, its contact R2 is closed.
Therefore, when a turn-on signal is input from the conductor f, the turn-on switch SWl is closed and the relay R1 is operated, and the power supply unit is turned on at its contact point, and the terminal device is started as shown in FIG. 5-2. While the terminal device is powered on, a disconnection signal is output from the main device a,
When a disconnection signal is input from logic section g to power supply unit e, disconnection switch SW2 closes and relay R2 operates. As a result, contact R2 opens and relay R1 turns off.
The contact opens and the power to power supply unit e is cut off.
Time t1 in FIG. 5 is the disconnection time from when the disconnection signal is output from main unit a until the contact of relay R1 opens.
While the disconnection switch SW2 is closed by the disconnection signal,
Of course, contact R2 of relay R2 opens, but even if disconnection switch SW2 opens after sending the disconnection signal, relay R2 has a time constant circuit h consisting of a capacitor and a resistor.
Since the discharge current flows from relay contact R during that time,
2 is held open. By the time the holding time due to the discharge current has elapsed, the sending of the closing signal from the main unit has finished, so even if the contact R2 of the relay R2 closes due to the end of the discharge, the error will not occur as explained in Figure 4. The power will not be turned on again. In this way, when the disconnection signal is no longer input, the disconnection switch Sw: opens, and the time T2 during which the relay contact R2 is opened by the discharge current of the time constant circuit is the reinsertion prohibition time, and T is the disconnection time of the main unit. , T<t1+T2 By setting the re-turning prohibition time T2 using the time constant circuit, re-turning due to malfunction can be reliably prevented.

The time constant circuit h for setting the re-input prohibition time T2 is only an example, and other means such as a timer may be used. Further, the circuit shown in FIG. 3 can also be constructed as a non-contact circuit.
Furthermore, instead of operating the time constant circuit etc. after the disconnection signal is no longer input, a timer etc. is started when the disconnection signal is input, and the timer etc. is started after the disconnection time T has elapsed. You can also do this. As described above, according to the present invention, the power supply unit is disconnected by using a special disconnection signal and determining it in the logic section of the terminal device. Since the disconnection state is maintained for a certain period of time, there is no risk of malfunction if the power is turned on again due to exposure to light after the termination of the disconnection signal.

Furthermore, since a special signal is used as the disconnection signal, there is no possibility that the power of the terminal device will be accidentally disconnected due to a drop in the signal level or a momentary power outage.

[Brief explanation of the drawing]

Figure 1 is a block diagram of a power supply remote control system that has already been tried, Figure 2 is a block diagram showing an embodiment of the power supply remote control system according to the present invention, and Figure 3 is a block diagram of a power supply unit re-inhibition circuit. As an example, Fig. 4 is a time chart of power on/off operation when the re-on prohibition circuit is not installed.
The figure is a time chart when a re-inhibition circuit is installed according to the present invention. In the figure, c... is an optical fiber cable, d
is an optical repeater, e is a power supply unit, g is a logic section, h is a time constant circuit, R1 and R2 are relays, and R2 is a relay connection AS.
SWl is a closing switch, and SW2 is a cutting switch.

Claims (1)

[Claims] 1. In a computer system in which a main unit and a terminal device are connected by an optical fiber cable, light arriving at an optical repeater provided in the terminal device is photoelectrically converted and input to a switch means that operates the power supply of the power supply unit of the terminal device. Occasionally,
Power is turned on by detecting that light has arrived at the optical repeater, and power is turned off by outputting a special disconnection signal from the main unit to the optical fiber cable and transmitting it via the optical repeater. This is done by inputting the signal into the logic section in the terminal device and inputting it as a disconnection signal to the switch means.On the other hand, in the power supply unit, a power re-inhibition circuit causes the power to be disconnected by the disconnection signal. A remote control method for a power supply, which is characterized in that the power supply is prohibited from being turned on again even if a power-on signal arrives for a predetermined period of time after the power supply has been turned on.