JPH1123634A - Noise monitoring device - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To provide a noise monitoring device that is easy to install, is effective in preventing malfunctions, and thus preventing accidents before they occur. SOLUTION: A shielded power relay cable 3 is used between a monitoring target device 1 and a device AC power outlet 4. A noise sensor 6 having an amorphous alloy core is attached to the ground wire of the shielded power relay cable 3 to extract noise that enters the monitored device 1. The noise sensor 6 and the noise monitoring device main body 5 are connected by a coaxial cable 7, converted into a pulse by a processing circuit section of the main body 5, and the magnitude and number are monitored and recorded in a time series. This continuous monitoring accumulates trend data and contributes to countermeasures against noise that occurs before malfunction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a noise monitoring device for monitoring noise entering an electric device or electronic device from a power supply unit thereof, thereby preventing a malfunction and consequently an accident.

[0002]

2. Description of the Related Art Various electric and electronic devices themselves become noise sources or are affected by incoming noise. The generation of noise is delicate, installing new equipment,
A change in the wiring route or the like may completely change the previous noise generation situation. The change is a phenomenon that is very hard to notice, such as knowing only when the device malfunctions.

[0003]

At present, there is no dedicated device for monitoring the change of the noise generation (intrusion) situation as a trend. Therefore, the investigation of the site starts after the device malfunctions. Intrusion) situation,
If there is a monitoring device that can grasp the trend, measures against noise can be taken before malfunctioning, and accidents can be prevented before it occurs.

The present invention has been made in view of the above circumstances, and converts noise entering a monitored device into a pulse.
An object of the present invention is to provide a noise monitoring device that is easy to install, and that is effective in preventing malfunctions and preventing accidents from occurring, by recording the levels and numbers in chronological order as judgment data.

[0005]

The present invention uses a shielded power relay cable between a device to be monitored and an AC power outlet for the device, and has a detection coil wound around a core attached to the ground wire. The noise that enters the monitored equipment is extracted by a noise sensor with a structured structure, converted into pulses by the processing circuit of the noise monitoring device, and the magnitude and number are monitored and recorded in chronological order to help understand trends. It is characterized by the following. In this case, the detection sensitivity is increased by using an amorphous alloy for the sensor core.

[0006]

1 and 2 show an embodiment of the present invention. FIG. 1 is an overall configuration diagram, and FIG. 2 is a block diagram showing a circuit configuration of a main body.

In FIG. 1, 1 is a device to be monitored, 2 is a power plug attached to the device 1 to be monitored, 3 is a shielded power relay cable, 4 is an AC power outlet for the device, 5 is a noise monitoring device main body, 6 Is a noise sensor attached to the ground wire of the shielded power supply relay cable 3, 7 is a coaxial cable connecting between the sensor input terminal of the noise monitoring device main body 5 and the noise sensor 6, 8 is Ethernet, and 9 is a personal computer. The personal computer 9 and the noise monitoring device main body 5 are connected by the Ethernet 8. The noise sensor 6 has a structure in which a detection coil is wound around a core of, for example, an amorphous alloy (a structure similar to a CT or a pulse transformer).

In FIG. 2, reference numeral 101 denotes a plurality of, for example, three noise sensors 6 when a plurality of devices are to be monitored.
An input switching circuit for switching the noise detection signals from 1 to 6-3, 102 is a filter circuit, and 103 is an amplifier (AM
P), 104 are pulsating circuits, 105 is a counting circuit for counting pulses, 106 is a comparing circuit, 107 is an alarm output circuit, 108 is a level setting circuit for determining noise exclusion criteria, 109 is a judgment reference value setting circuit, 110 Is a count value accumulation circuit, 111 is a hard disk drive (HDD), and 112 is a LAN board. From the filter circuit 102 to the alarm output circuit 107, the input switching circuit 1
01 is provided in series in a series, and each setting signal is applied to the pulsing circuit 104 from the level setting circuit 108, and to the comparing circuit 106 from the determination reference value setting circuit 109. The output of the circuit 105 is branched and input to the count value accumulation circuit 110. The hard disk of the HDD 111 stores (1) pulse level setting value, (2) pulse count value, (3) judgment reference value, (4) alarm output result, (5) date / time data, etc. The data is stored and uploaded to the host personal computer 9 via the Ethernet 8 via the LAN board 112.

Next, the operation will be described. The noise passing through the power cable is captured by the shielded wire 3, extracted by the noise sensor 6 (6-1, 6-2 or 6-3) when flowing into the ground, and sent to the apparatus main body 5 by the coaxial cable 7. In the apparatus main body 5, after being selected by the input switching circuit 101, a signal in a noise band is extracted by the filter circuit 102 and amplified by the AMP 103. In the amplified signal, a signal having a level equal to or higher than the level set by the pulse generator 104 is pulsed. This pulse is counted by the counting circuit 105, and is compared by the comparison circuit 106 with the set pulse number of the criterion. The comparison result is transmitted to the alarm output circuit 107. Alarm output circuit 107
If the comparison result exceeds the determination level, the lamp on the front panel is turned on.

The following data is stored on a hard disk, uploaded to the host PC 9 via the Ethernet 8 via the LAN board 112, and processed there.

(1) Pulse level setting value (2) Pulse count value (3) Judgment reference value (4) Result of alarm output (5) Year / month / time data Judgment at the time of noise pulse conversion and level judgment If the criterion is set in two stages, it is possible to know the change of the noise intrusion situation macroscopically. Also, graphing the time-series data shows the trend of change (change of day, change of week, etc.) at a glance, and knowing the sudden increase point of the noise will help to find the cause of the noise. As a result, the device environment can be improved before the monitored device malfunctions due to the alarm system.

[0012]

As described above, according to the present invention, noise entering a monitoring target device is converted into a pulse, and its level,
Since the numbers are recorded in chronological order to contribute to the determination, it is possible to take measures against noise before the device malfunctions, thereby preventing accidents from occurring. In addition, use a shielded power relay cable and connect the ground wire to C
Since a noise sensor having a structure similar to that of T or the like is provided, it is extremely easy to mount the device on a monitoring target device. Moreover,
A plurality of target devices can be monitored by one monitoring device.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram showing an embodiment of the present invention.

FIG. 2 is a block diagram showing a circuit configuration of a main unit according to the embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Monitoring target equipment 2 ... Power plug 3 ... Power supply relay cable with shield 4 ... AC power supply for equipment 5 ... Noise monitoring device main body 6 ... Noise sensor 7 ... Coaxial cable 8 ... Ethernet 9 ... Personal computer 101 ... Input switching circuit 102 ... Filter Circuit 103 ... Amplifier 104 ... Pulsing circuit 105 ... Counting circuit 106 ... Comparison circuit 107 ... Alarm output circuit 108 ... Level setting circuit 109 ... Judgment reference value setting circuit 110 ... Count value accumulation circuit 111 ... HDD 112 ... LAN board

Claims (1)

[Claims] An object to be monitored is a noise sensor having a structure in which a detection coil is wound around a core, wherein a shielded power supply relay cable is used between a device to be monitored and an AC power outlet for the device. Noise that extracts noise entering the equipment, converts it into pulses in the processing circuit of the noise monitoring device body, monitors and records the magnitude and number in time series, and helps to understand trends Monitoring device.