JPH02118463A - Voltage abnormality detector - Google Patents

Abstract

PURPOSE:To detect voltage abnormality due to the length of a power cord by providing a means which compares voltages measured while an equipment is not in operation and in operation and their potential difference with the preset maximum permissible value of the potential difference. CONSTITUTION:A CPU 44 stores a RAM 42 with the voltage measured by a voltage measuring instrument 40 while the equipment is not in operation as a 1st measured voltage and the operation measured while the equipment is in operation as a 2nd measured voltage. Further, the lower limit value of a source voltage at which the operation of the equipment becomes abnormal is set in a ROM 46 as a 1st reference value and the maximum permissible value of the potential difference between the nonoperation voltage and operation voltage as a 2nd reference value. Then when the 1st measured voltage in the RAM 42 is lower than the 1st reference value in the ROM 16, it is judged that an abnormal voltage is generated and an abnormality signal is outputted to a 1st warning device 48. Further, when the 1st measured voltage is larger than the 1st reference value, the potential difference between the 1st and 2nd measured voltages in the RAM 42 is computed and when this computed value is larger than the 2nd reference value, it is judged that the extension cord is too long, so that an abnormality signal is outputted to a 2nd warning device.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a voltage abnormality detection device, and more particularly to an improvement in a device for detecting voltage abnormality in equipment to which drive power is supplied via a power cord.

[Prior Art] Various types of OA equipment used in offices today are designed to be supplied with driving power via power cords. Many devices in which the current used changes significantly due to deafness are equipped with a voltage abnormality detection device that detects whether or not driving power is being supplied at a normal voltage.

Conventionally, such a voltage abnormality detection device includes a measuring means for measuring the voltage of driving power supplied via a power cord;
The storage means includes a storage means in which a voltage that causes an abnormal operation of the device is recorded as a voltage.

The measured voltage and the reference voltage are then compared, and if it is determined that the device cannot operate normally as a result of the comparison, a warning is generated.

[Problems to be solved by the invention] By the way, various OA equipment used in offices etc.
It is often used by connecting an extension cord to the power cord.
In such cases, it is often possible to avoid voltage abnormalities in the equipment simply by removing the extension cord.

However, since the conventional device simply compares the measured voltage and the reference voltage, it is possible to detect an abnormality in the voltage of the power supply, but the cause of the voltage abnormality cannot be identified. There was a problem in that even if it was possible to avoid it, it was not possible to notify the user.

For this reason, once a voltage abnormality is detected, the OA equipment cannot be used until it is repaired by specialized maintenance personnel, and an effective countermeasure has been desired.

The present invention was made in view of such conventional problems, and its purpose is to replace voltage abnormalities caused by the length of the power cord, which can be easily avoided by the user, with voltage abnormalities caused by other causes. I identified this and went out on a limb.

- To provide a voltage abnormality detection device capable of warning the user.

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a means for measuring the voltage of the drive power in a device to which drive power is supplied via a power cord, and a means for measuring the voltage of the drive power when the device is not in operation. Measured voltage storage means for storing a first measured voltage to be measured and a second measured voltage to be measured during operation, and a basis for setting a maximum allowable value of a potential difference between a drive voltage that occurs when the device is not in operation and when the device is in operation. a comparison means for outputting an abnormality detection signal when the potential difference between the first measured voltage and the second measured voltage exceeds the maximum allowable value; This detects voltage abnormalities caused by the length of the

[Action Co. Next, the present invention will be explained in detail.

Among devices to which driving power is supplied via the fM power cord, there are many devices, such as copying machines, in which the current that flows is small when the device is not in operation, and extremely large when it is in operation.

When such equipment is operated with a large current flowing through it, there is a large voltage drop due to the power cord, and if the power cord is too long, the driving power voltage may drop below the voltage required for the equipment to operate normally. There are many cases where this happens.

The present inventors believe that if voltage abnormalities caused by the length of the power cord manifest as a potential difference between the drive voltage when the device is not operating and the drive voltage when the device is operating, voltage abnormalities caused by other causes may occur. We have found that it can be identified and detected as an abnormality.

For this reason, the voltage of the driving power is measured using a δp1 constant means, and the voltage measured when the device is not operating is set as the first measured voltage, and the voltage measured when the device is operating is set as the second measured voltage and the measured voltage is stored. Write down the means.

Further, the maximum allowable value of the potential difference that occurs when the device is not in operation and when it is in operation is set in advance in the reference value storage means.

When the potential difference between the first measured voltage and the second measured voltage exceeds the maximum allowable value, this is determined to be a voltage abnormality caused by the length of the power cord, and an abnormality detection signal is sent from the comparison circuit. Output.

In this way, the device of the present invention can distinguish voltage abnormalities caused by the length of the power cord from voltage abnormalities caused by other causes and notify the user.

Therefore, by using the voltage abnormality detection device of the present invention, a user can distinguish voltage abnormalities caused by the length of the power cord from voltage abnormalities caused by other causes, and can detect such voltage abnormalities. When a voltage abnormality is detected, it is possible to easily avoid the voltage abnormality by removing the extension cord being used.

[Example] Next, preferred embodiments of the present invention will be described based on the drawings.

FIG. 2 shows a preferred embodiment in which the present invention is applied to a copying machine.

The copying machine 10 of the embodiment has a power cord 20 having a plug 22 at the tip thereof, and is configured so that driving power is supplied by inserting the plug 22 into an FCS power outlet 24.

Generally, such a copying machine 10 is connected to an outlet 24 via a power cord 20 as shown in FIG. It is often used by connecting an extension cord 26 to the cord 20. Typically, such an extension cord 26 is
A tap 30 to be connected to the plug 22 is provided at one end, and a plug 28 to be inserted into the power outlet 24 is provided at the other end.

When such an extension cord 26 is used, the distance of the power line from the Tl5K outlet 24 to the main body of the copying machine 10 becomes long, and the voltage drop along this line becomes non-negligible.

Here, when using a copying machine 10 with a current flowing when using a power supply of 100 volts, the current flowing is about 1 to 2 amperes during non-exposure (non-operating) and 15 amperes during exposure (operating), and a certain power cord is used. When the driving voltage VP at the connection point P between the copying machine 20 and the copying machine 10 was measured, the driving voltage (2) was as shown in FIG.

As is clear from this measurement example, when the copying machine 10 is directly connected to the electrical outlet 24 via the power cord 20, the potential difference between the non-exposed state and the exposed state is approximately 95-92-3 volts. On the other hand, it is understood that when the copying machine 10 is connected to the outlet 24 via the power cord 20 and the extension cord 26, the potential difference becomes 95-85-10 volts, which is three times as large.

In particular, the longer the extension cord 26 used, the more
This voltage drop becomes even larger, and in the worst case, the voltage drops to such an extent that normal operation of the copying machine 10 is prevented.

A feature of the present invention is that voltage abnormalities caused by the power cord 20 and extension cord 26 are detected separately from voltage abnormalities caused by other causes, and the user is notified of this.

FIG. 1 shows a preferred example of the voltage abnormality detection device of the present invention provided in a copying machine 10 in order to detect such voltage abnormalities.

The voltage abnormality detection device (hereinafter referred to as the detection device) of the embodiment includes a voltage measuring device 40 that determines the voltage V at the measurement point P shown in FIG.
including.

Moreover, this detection device is provided with a CPU 44,
The CPU 44 determines that the copying machine 10 is in a non-exposed state when the halogen lamp 12 is OFF.

At this time, the voltage V output from the voltage measuring device 40
P is the first measured voltage (■) and written in the RAM 42. Further, if the halogen lamp]2 is ON, it is determined that the copying machine 10 is in an exposure state, and the voltage VP output from the voltage measuring device 40 at this time is set as the second measured voltage VP2.
It is formed so as to be written into the RAM 42 as a.

The detection device of the embodiment also includes R as a reference value storage means.
An OM 46 is provided, and in this ROM 46, a lower limit value of the power supply voltage that causes an abnormality in the operation of the copying machine 10 is stored.
The reference value VSI of the copying machine 10 is set as the reference value VSI, and the voltage VPI of the copying machine 10 during non-exposure and the voltage VP during exposure
2 or the maximum allowable potential difference with the second group L'jp, fa
It is set as VS2.

Then, the CPU 44 selects the first measured voltage Vl"l stored in the RAM 42, that is, the measured voltage V, 1 when the copy 110 is not exposed, and the first base value preset in the ROM 46. When the first measured voltage VPI is less than the first base value VS1, it is determined that the drive voltage is too low and is interfering with the normal operation of the copier. , outputs a first abnormality detection signal to the first warning device 48.

As a result, the warning device 48 displays a warning to the user of the occurrence of an abnormality in the power supply voltage.

Mata, CPU 44 +; i, first measurement 1u pressure v,
, is larger than the first reference value VSI, then the first δIII constant voltage V stored in the RAM 42
Potential difference V-V between PI and second all constant voltage VP2
ptoVp2 is calculated, and it is determined whether this calculated value V is larger than a second reference value V3□ registered in advance in the ROM 46.

If this potential difference V is larger than the second value VS2, it is assumed that the power line connecting the copying machine 10 and the outlet 24 is too long, and the second abnormality detection signal is output to the second error detection signal. The information is output to the warning device 50.

As a result, the second warning device 50 displays a warning to the user that the extension cord 26 is too long.

The present embodiment has the above configuration, and its operation will be explained next.

FIG. 4 shows a flowchart showing the operation of this embodiment.

When the power of the copying machine 10 is turned on, the abnormality detection device of the embodiment first resets the RAM 42 (Sl), and then detects whether the halogen lamp 12 is lit (S1).
S2) When the halogen lamp 12 is turned off, its measured voltage V is set as the first measured voltage V, 1, and R
Write to AM42 (S3), and halogen lamp 12 is turned on.

when the measured voltage V is the second measured voltage V
It is written to RAM 42 as P2 (S4).

Then, the CPU 44 compares the first measurement voltage VPI written in the RAM 42 with the first reference voltage VSI registered in advance in the ROM 46 (S5), and determines whether the first measurement voltage VPI or the first reference voltage If the voltage falls below VSI, it is determined that a voltage abnormality has occurred, and the first warning device 48 is used to notify the user of this fact (S6).

Therefore, in this case, the user may request the maintenance company of the copying machine 10 to repair the voltage abnormality, for example, by telephone.

Further, when the first measurement voltage VPI is higher than the first base voltage VSI, the CPU 44 next calculates the first measurement voltage V, 1 and the second measurement voltage VP2 stored in the RAM 42. The potential difference V is determined (S7), and this potential difference V is RO
It is determined whether or not the value is greater than or equal to the second basic emblem value V52 registered in advance in M46 (S8).

If the calculated potential difference V is greater than or equal to the second voltage VS□, it is determined that the extension cord 26 is too long and the voltage drop is too large, and a second warning device 50 is used to notify The user is warned (S9).

In this case, as shown in Figure 2 (B), remove the extension cord 46 and plug the power cord 20 directly into the plaque 24 until you request a maintenance company to repair it. Therefore, voltage abnormalities can be easily avoided within a month.

Incidentally, if VF6 is not written in the RAM 42 in S3, that is, if the halogen lamp 12 has never been lit, the processing in S7 and S8 is ignored and the process returns directly to step S2.

As described above, according to the present embodiment, the second warning device 50 and the first warning device 48 are used to issue a warning due to the extension coat 26 being too long and a warning due to other causes. By distinguishing between the extension cords 26 and 26, when the user receives a warning that the extension cord is too long, the user can easily avoid voltage abnormalities by simply removing the extension cord 26, making the handling much more convenient than before. Become.

Although the present embodiment has been described with reference to the case where the voltage abnormality detection device is provided in the copying machine 10, the present invention is not limited to this and can be widely used in various other devices.

[Effects of the Invention] As explained below, according to the present invention, it is possible to distinguish a voltage abnormality caused by the length of a power cord from a voltage abnormality based on other causes and to warn the user. Users should be able to clearly distinguish voltage abnormalities caused by long power cords from other abnormalities (7). It has the effect of being able to avoid abnormalities.

[Brief explanation of drawings]

FIG. 1 is a block circuit diagram showing a preferred example of a case where the voltage abnormality detection device according to the present invention is applied to a copying machine, FIG. 2 is an explanatory diagram of the usage state of the device, and FIG. (B) is an explanatory diagram when the device is connected to an outlet directly via a power cord and an extension cable. An explanatory diagram showing an example of the measured voltage at the measurement point P in A) and (B), and FIG. 4 is a flowchart showing the operation of the circuit shown in FIG. 1. 40... Voltage measuring device, 42... RAM as measured voltage storage means. 44...CPU as comparison means. 46... ROM as basic value storage means, 50...
Second warning device. Agent Patent attorney, J No. 1 - (2 others) Figure 2 (A) (B) Figure 2

Claims (1)

[Claims] (1) In a device to which driving power is supplied via a power cord, a means for measuring the voltage of the driving power, a first measurement voltage measured when the device is not in operation, and a second measurement voltage measured when the device is in operation. Measured voltage storage means for storing the voltage; Reference value storage means for setting the maximum allowable value of the potential difference between the driving voltages that occurs when the device is not in operation and when the device is in operation; A voltage abnormality comprising: a comparison means for outputting an abnormality detection signal when the potential difference exceeds the maximum allowable value, and detects a voltage abnormality caused by the length of the power cord based on the abnormality detection signal. Detection device.