JPH04258769A - Electromagnetic interference detecting device - Google Patents

Abstract

PURPOSE:To detect the presence of the interference occurrence of an electronic device without affecting the electromagnetic environment around the electronic device or being affected by it. CONSTITUTION:The light of an interference detecting lamp informing the interference occurrence of an electronic device is received by a light reception section 1, and the received light is sent to a necessary position with an optical fiber 3 as the light signal. The light signal is converted into the electrical signal by a light/electricity converting circuit 4 to detect interference occurrence. When the optical fiber 3 is used, no effect is given to the electromagnetic environment around the electronic device, and no effect is given from the ambient electromagnetic environment.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetic interference detection device for detecting electromagnetic interference in electronic equipment caused by various electromagnetic interference waves.

0002

[Prior Art] In recent years, electromagnetic pulses caused by electrostatic discharge, electromagnetic pulses emitted from power tools and fluorescent lamps, and electromagnetic interference waves from amateur radio and CB radio can cause malfunctions and destruction of electronic devices. It is causing a problem. This type of electromagnetic environment is worsening due to a decline in the noise tolerance of electronic devices to electromagnetic interference waves due to faster operating speeds and lower power consumption of semiconductor devices, and a significant increase in the number of electronic devices that generate electromagnetic interference waves. It's exacerbating the problem. Most of the electromagnetic interference waves that cause electromagnetic interference are high-speed and transient phenomena, so it is often difficult to identify when interference is induced in electronic equipment, and there are no countermeasures. in a situation that is not well established.

[0003] Therefore, it is necessary to understand the electromagnetic environment at the time when a failure occurs in electronic equipment, and to clarify the correlation between the understood electromagnetic environment and electromagnetic interference in electronic equipment, in order to establish countermeasures against electromagnetic interference in electronic equipment. is important above. To achieve this, it is first necessary to accurately detect the occurrence of a failure in the electronic device without affecting the electromagnetic environment surrounding the electronic device.

[0004] Conventionally common fault detection methods include visually checking a fault detection lamp provided on an electronic device, or outputting an electric signal indicating the occurrence of a fault on an electronic device. There are several ways to wire to the output terminal. In addition, in cases where such failure detection lamps or output terminals are not available, a method has been adopted in which the internal circuit of the electronic device is changed to extract the necessary electrical signals and wired thereto.

[0005]

However, among the fault detection methods according to the above-mentioned conventional techniques, it is impossible to detect faults with high accuracy by visually observing fault detection lamps. Further, in the method of wiring the output terminal or internal circuit of the electronic device, the wiring ends up affecting the electromagnetic environment around the electronic device.

The present invention has been made to solve the above-mentioned problems, and its purpose is to detect a failure with high precision without affecting the surrounding electromagnetic environment when a failure occurs in an electronic device. The object of the present invention is to provide an electromagnetic interference detection device that can notify whether or not a failure has occurred.

[0007]

[Means for Solving the Problems] In order to achieve the above object, one configuration of the electromagnetic interference detection device of the present invention includes a light receiving section that receives light from a fault detection lamp of an electronic device; It is characterized by comprising an optical fiber that transmits the optical signal as an optical signal, and an optical-electrical conversion circuit that converts the optical signal from the optical fiber into an electrical signal.

[0008] In another configuration of the electromagnetic interference detection device of the present invention, instead of the above-mentioned light receiving unit, an electric signal detection unit that detects an electric signal related to failure detection of an electronic device;
It is characterized by using a signal level determination circuit for the electric signal from the electric signal detection section and an electric-optical conversion circuit that converts the electric signal from the signal level determination circuit into an optical signal.

[0009]

[Operation] In the electromagnetic interference detection device of the present invention, the light from a failure detection lamp that indicates the occurrence of a failure in an electronic device or an electric signal inside the electronic device is transmitted as an optical signal through an optical fiber to a necessary location, and the optical signal is converted into an electric signal. Detects the occurrence of a failure by converting it into a signal. In other words, by eliminating wiring for transmitting electrical signals, it is possible to not affect the electromagnetic environment around electronic devices, and it is also less susceptible to the effects of the surrounding electromagnetic environment, allowing for highly accurate failure detection. enable.

0010

Embodiments Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a diagram showing the basic configuration of a first embodiment of the present invention. This embodiment is an example in which a failure detection lamp of an electronic device is used. In FIG. 1, 1 is a light receiving section that receives light from a fault detection lamp of an electronic device (not shown), 2 is a cover for the light receiving section 1, 3 is an optical fiber that transmits the light received by the light receiving section 1 as an optical signal, and 4 is its This is an optical-to-electrical conversion circuit that converts optical signals into electrical signals.

The light receiving unit 1 is surrounded by a cover 2 to prevent ambient light from entering, and the tip of the optical fiber 3 may be attached directly to the fault detection lamp, or the optical fiber 3 may be attached directly to the fault detection lamp. This can be achieved by attaching a cell-hock lens to the tip of the lens. As the optical fiber 3, commercially available products such as plastic fibers and bundle fibers can be used. Further, the optical-electrical conversion circuit 4 can be easily manufactured by using a photodiode, an optical signal module, or the like.

The operation and effects of the first embodiment configured as above will be described.

When a fault is induced in an electronic device having a fault detection lamp, such as a transmission device or a switch, the fault detection lamp emits light, and the light is detected by the light receiving section 1. next,
The optical signal from the light receiving section 1 is transmitted to a desired location via an optical fiber 3, and is converted into an electrical signal by an optical-electrical conversion circuit 4. This electrical signal is sent to means for detecting the occurrence of electromagnetic interference in the vicinity, and the occurrence of electromagnetic interference is detected there by determining the level of the electrical signal. As described above, according to this embodiment, since the light from the failure detection lamp of the electronic device is used, there is no need to make any changes to the internal circuit of the electronic device, and moreover, the optical fiber is used for transmission. , it becomes possible to realize an electromagnetic interference detection device that does not affect the surrounding electromagnetic environment and is not influenced by the surrounding electromagnetic environment.

Next, a second embodiment of the present invention will be described.

This embodiment shows an example of a failure detection system using the electromagnetic interference detection device of the first embodiment. FIG. 2 shows a configuration diagram thereof, and among the reference numerals in the figure, 1 to 4 having the same reference numerals as those in FIG. 1 are the constituent parts described in the first embodiment. Other components include an electronic device 5, a fault detection lamp 6 provided on the electronic device 5, a digital oscilloscope 7, and an antenna 8. Optical-electric conversion circuit 4
The electrical signal from the antenna 8 and the received signal from the antenna 8 are input to the digital oscilloscope 7.

In the above example of the failure detection system, the operation will be described in a situation where electromagnetic interference occurs in the electronic device 5 due to electromagnetic waves emitted by a fluorescent lamp or the like. When electromagnetic interference is induced and the failure detection lamp 6 of the electronic device 5 emits light, the light is detected by the light receiving unit 1. Next, the optical signal from the light receiving section 1 is transmitted to a digital oscilloscope 7 via an optical fiber 3.
The signal is transmitted to the vicinity of , and is converted into an electrical signal in the optical-to-electrical conversion circuit 4. Then, an electrical signal from the optical-to-electrical conversion circuit 4 is input to the digital oscilloscope 7 as a trigger signal. During this time, the digital oscilloscope 7 continues to measure electromagnetic interference waves in the space using the antenna 8, but is set to stop updating the measurement data when the trigger signal is input. Furthermore, it is possible to adjust how far back in time measurement data is accumulated from the time the trigger signal is input to the digital oscilloscope 7 by setting an arbitrary delay time in advance. . That is, it becomes possible to measure the electromagnetic environment around the electronic device 5 from the time when the signal from the optical-to-electrical conversion circuit 4 is input to the time when a failure occurs in the electronic device 5.

Next, a third embodiment of the present invention will be described.

FIG. 3 shows its configuration diagram. In this example,
An example of detecting electromagnetic interference from the internal circuit of an electronic device is shown. In FIG. 3, 3 is an optical fiber, 5 is an electronic device, 9 is an internal circuit of the electronic device 5, 10 is a voltage detection section,
11 is a voltage level determination circuit, and 12 is an electrical-optical conversion circuit. The voltage detection section 10 can be easily manufactured by a voltage probe, the voltage level determination circuit 11 can be easily manufactured by combining an inverter and a comparator, and the electric-optical conversion circuit 12 can be easily manufactured by using a light emitting diode. Here, the voltage detection unit 10 is connected to a location where a voltage associated with a failure occurs in the internal circuit 9, and the detected voltage is inputted to the electro-optical conversion circuit 12 through the voltage level determination circuit 11. The optical signal from this electric-to-optical conversion circuit 12 is guided to the optical fiber 5 and transmitted to an optical-to-electrical conversion circuit (not shown) disposed at a necessary location.

In the third embodiment of such a configuration,
The operation will be described assuming that a failure occurs in the electronic device 5 and a voltage exceeding a normal level is applied to the internal circuit 9. At this time, if the voltage level from the voltage detection section 10 exceeds a preset range, the voltage level determination circuit 11 outputs an electrical signal. This electrical signal is converted into an optical signal in the electrical-optical conversion circuit 12 and transmitted via the optical fiber 3. The functions after the optical fiber 3 are the same as in the first embodiment.

According to this embodiment, the electrical signal of the internal circuit 9 that indicates a fault that has occurred in the electronic device is converted into an optical signal nearby and transmitted to the required location using the optical fiber 5, so that it is not affected by the surrounding electromagnetic environment. The function of detecting the occurrence of a fault can be realized without affecting the electromagnetic environment and without being influenced by the surrounding electromagnetic environment.

Next, a fourth embodiment of the present invention will be described.

FIG. 4 shows its configuration diagram. In this example,
Another example of detecting electromagnetic interference from the internal circuit of an electronic device is shown. In FIG. 4, 3 is an optical fiber, 5 is an electronic device, 9 is an internal circuit of the electronic device 5, 12 is an electro-optical conversion circuit, 13 is a current detection section, and 14 is a current level determination circuit. The current detection unit 14 can be easily constructed by inserting a resistor that is sufficiently smaller than the resistance value of the element in series with a specific element of the internal circuit of the electronic device, and measuring the voltage value across the resistor. Furthermore, the current level determination circuit 14 can be easily manufactured by combining an inverter, a comparator, and the like. Here, in this embodiment, the current detection section 13 is inserted into a signal generation point related to the occurrence of a fault in the internal circuit 9 of the electronic device 5, the signal current is detected, and the detected current is sent to the current level determination circuit 14. The signal is input to the electrical-to-optical conversion circuit 12 via. In addition, the electric-optical conversion circuit 12
The optical signal from the optical fiber 5 is guided to an optical fiber 5 and transmitted to an optical-to-electrical conversion circuit (not shown) disposed at a necessary location.

In the fourth embodiment configured as described above, the operation will be described assuming that a failure occurs in the electronic device 5 and a current exceeding a normal level flows through the internal circuit 9. At this time, if the current level from the current detection section 13 exceeds a preset range, the current level determination circuit 14 outputs an electrical signal. This electrical signal is converted into an optical signal in the electrical-optical conversion circuit 14 and transmitted via the optical fiber 3. The functions after the optical fiber 3 are the same as in the first embodiment. According to this embodiment, the electrical signal of the internal circuit 9 that informs of a fault that has occurred in the electronic device 5 is converted into an optical signal nearby and transmitted to the required location using the optical fiber 5, so that there is no influence on the surrounding electromagnetic environment. It is possible to realize the function of detecting the occurrence of a fault without causing any interference or being affected by the surrounding electromagnetic environment.

[0025]

As is clear from the above description, the electromagnetic interference detection device of the present invention detects a signal indicating the occurrence of a failure in an electronic device as an optical signal, and transmits it to a required location using an optical fiber. Since the system detects the occurrence of a failure by converting it into an electrical signal, it is possible to detect whether a failure has occurred in the electronic device without affecting the electromagnetic environment surrounding the electronic device, and without being affected by the surrounding electromagnetic environment. This has the advantage of being able to notify the occurrence of a failure with high accuracy. The present invention makes it possible to measure the electromagnetic environment around electronic devices when electromagnetic interference occurs, which leads to elucidation of the causes of failures in electronic devices and the establishment of techniques for countermeasures against electromagnetic interference, which is extremely effective.

[Brief explanation of the drawing]

[Fig. 1] Block diagram showing the first embodiment of the present invention

[Figure 2
] A configuration diagram showing a second embodiment of the present invention in which the first embodiment is applied to a failure detection system.

[Figure 3] Configuration diagram showing a third embodiment of the present invention

[Figure 4] Fourth aspect of the present invention
A configuration diagram showing an example of

[Explanation of symbols]

1... Light receiving part, 2... Cover, 3... Optical fiber, 4... Light -
Electrical conversion circuit, 5...Electronic device, 6...Fault detection lamp, 7
...Digital oscilloscope, 8. Antenna, 9. Internal circuit of electronic device 5, 10. Voltage detection section, 11. Voltage level determination circuit, 12. Electrical-optical conversion circuit, 13. Current detection section, 14. Current level determination circuit. .

Claims (2)

[Claims] 1. A light receiving section that receives light from a failure detection lamp of an electronic device, an optical fiber that transmits the light received by the light receiving section as an optical signal, and an optical-electrical cable that converts the optical signal from the optical fiber into an electrical signal. An electromagnetic interference detection device comprising a conversion circuit. 2. The electromagnetic interference detection device according to claim 1, in which the light receiving section is replaced by an electrical signal detection section that detects an electrical signal related to fault detection of an electronic device, and an electrical signal detection section that detects an electrical signal from the electrical signal detection section. An electromagnetic interference detection device characterized by using a signal level determination circuit and an electrical-optical conversion circuit that converts an electrical signal from the signal level determination circuit into an optical signal.