JPH0396871A - Online diagnosis method and device for electromagnetic equipment - Google Patents

Abstract

PURPOSE:To detect abnormality of the driving circuit by applying a test signal of time width in which an electromagnetic apparatus does not operate to the driving circuit, inputting a current detection value in its circuit to a level shifting means and a delaying means and a comparing means, and comparing the result of its comparison and the test signal. CONSTITUTION:At the time of on-line diagnosing a switch 3 and an electromagnetic apparatus 2 being a driving circuit, a current flowing through the switch 3 is detected through a resistance 4, the result of its detection is inputted to a level shifting circuit 8 and a delaying circuit 9 and both outputs are compared by a comparing circuit 10. Also, a signal passing through a window circuit 12 and the output signal of the circuit 10 are allowed to take AND by a comparing circuit 13, its result is decided by fault deciding circuits 14A, 14B, and in that case by setting a test signal from a circuit 11 as a test signal of time width in which the apparatus 2 does not operate, a diagnosis of the driving circuit is executed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an online diagnostic device for electromagnetic devices such as electromagnetic relays and electromagnetic switches, and edge drive circuits.

[Prior Art] Many electromagnetic devices such as electromagnetic relays and electromagnetic switches are used in various power generation plants including atomic couplants, steel plants, chemical plants, and the like. These electromagnetic devices are usually in a standby state, and are often used in so-called standby mode, in which they are activated when an operation request occurs. In such cases, it is important for the safe operation of the plant to be able to know in advance whether or not the electromagnetic equipment will actually operate when there is someone to operate it, without operating the electromagnetic equipment. There is a strong demand for diagnosis of equipment and its drive circuits.

The failure detection device for electromagnetic equipment disclosed in Japanese Patent Application Laid-open No. 53-41971 detects that when an operation command is given to the electromagnetic equipment, the inductance of the excitation coil of the electromagnetic equipment changes as the movable part of the equipment moves. A failure of the electromagnetic device is detected by detecting the extreme value of the excitation current that occurs according to the change and determining whether or not the electromagnetic device has actually operated. Changes in the excitation current are detected by a comparison circuit that inserts a resistor into the drive circuit, detects the excitation current flowing through the resistor in the form of voltage, and compares this detection signal with a signal obtained via a delay circuit. It is detected by

In addition to this conventional example, JP-A-53-21392, JP-A-5
There are No. 4-159584 and JP-A-63-135679. All of these are related to failure diagnosis of solenoid valves.

[Problem to be solved by the invention]

In the above-mentioned Japanese Patent Laid-Open No. 53-41.971, a failure of the electromagnetic equipment is detected by detecting the extreme value of the excitation current that occurs with the operation of the electromagnetic equipment. When a test signal is applied to the drive circuit, the electromagnetic device does not operate, so the inductance of the excitation coil does not change.

As a result, although a slight change occurs in the excitation current, there is no extreme value. Therefore, in such a case, there is a problem in that the conventional technology cannot detect abnormalities in the electromagnetic equipment and the vibration circuit.

In addition, in the above conventional technology, a resistor is inserted directly into the drive circuit to detect the excitation current, but if the electromagnetic equipment is of a type that operates with the excitation current off, if the resistor fails on the disconnection side. , there is a problem that the electromagnetic equipment malfunctions and high reliability of the system cannot be ensured.

Also, JP-A-53-21392, JP-A-54-159
No. 584 and Japanese Unexamined Patent Publication No. 63-135679 also do not describe the application of a test signal with a time width that does not cause electromagnetic equipment to operate.

The present invention has been made in view of the above points, and an object of the present invention is to first provide a device that can diagnose electromagnetic equipment and its phasing circuit without operating the equipment.

[Means to solve the problem]

The present invention applies a test signal with a time width during which the electromagnetic device does not operate to a drive circuit of an electromagnetic device, detects a current in the driving circuit, and applies this detected current to a level shift means, a delay means, and a comparison means. The response of the drive circuit upon application of the test signal is detected by inputting the signal into a circuit consisting of the following, and the result of this detection is compared with the test signal for determination.

[For production]

The present invention applies a test signal with a time width during which the electromagnetic device does not operate to a drive circuit of an electromagnetic device, and uses a level shift means and a delay means to adjust the amount of minute change in the current flowing in the drive circuit in response to the test signal. Since detection can be performed using a circuit consisting of the electromagnetic device and the comparison means, the electromagnetic device and its drive circuit can be diagnosed without operating the electromagnetic device.

〔Example〕

Embodiments according to the present invention will be described below with reference to the drawings. Portions with equal numbers each time indicate corresponding portions.

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

The electromagnetic device 2 shown in this embodiment is of a type that is normally in an energized state and operates in a non-excited state when a switch 3, which is a drive circuit, is opened. It is not limited to. A structure that operates in this way is generally called a fail-safe structure; for example, even if the power supply 1 is lost, the electromagnetic device will continue to operate, and is used in cases where high safety is required. often used for

A diagnostic device for determining whether or not the electromagnetic equipment 2 configured in this manner and its purification circuit are healthy or not is constructed as follows.

First, the current flowing through the drive circuit is detected in the form of voltage via the resistor 4. This is connected to a level shift circuit 8 and a delay circuit 9.
and a comparison circuit 10 that compares these output signals, and inputs the output signal 7 of the input signal tracking type comparison circuit 6, which is outputted as a result, from the test signal generation circuit 1. The output test signal and the signal obtained via the window circuit 12 are ANDed by the digital comparison circuit 13, and this result is sent to the failure determination circuit 1.
4A and 14B and display the diagnosis results.

Now, the operation of the diagnostic apparatus constructed in this way will be explained using FIG. 2.

Figure 2 (a) is a diagram showing the operating waveforms of each part when the drive circuit 3 and electromagnetic equipment 2 are normal, and Figure 2 (b) is a diagram showing the operation waveforms of each part when the drive circuit 3 is in a closed state. FIG.

First, a case where the drive circuit 3 is normal is shown using FIG. 2(a).

The test signal 11A shown in (IV) of FIG.
Output to 2. This test signal 11A is a pulse signal with a time width during which the electromagnetic device 2 does not operate. Application of this test signal causes the switch of the drive circuit 3 to be in an open state for a short period of time. Therefore, the current flowing through the oscillation circuit 3 becomes zero during this period.

In FIG. 2(a), the test signal is applied when the current in the drive circuit, that is, the current flowing through the electromagnetic device, is exactly zero, so the current detected by the resistor 4 is also After the current reaches zero, it remains zero for as long as the test signal is applied.

Then, when the test signal is released and the switch of the drive circuit 3 returns to the closed state, current flows from that point on. Therefore, the current detected by the resistor 4 is (
The current detection signal 5 is shown in V).

Note that if the test signal is not applied, the electromagnetic device 2
The current flowing through is determined by the voltage of the power supply and the impedance of the excitation coil of the electromagnetic device 2.

Now, the current detection signal 5 is processed by the input signal tracking type comparison circuit 6 as follows. Current detection signal 5 is input to delay circuit 9 . This delay circuit 9 can be realized by a filter circuit, and its output becomes the delayed signal 9A shown in (V) of FIG. 2(a). In this way, the current detection signal 5 and this delayed signal 9A do not overlap when the test signal is applied, so whether or not the drive circuit 3 is operated by the test signal and current no longer flows to the electromagnetic device can be determined by using these two signals as they are. You can't judge by comparing. Therefore, the current detection signal 5 is also input to the level shift circuit 8, and a signal lower by a certain level than the current detection signal is outputted from the level shift circuit 8.
This output signal and the delayed signal 9A are made to cross each other on the waveform and then compared. The level-shifted signal 8A, which is the signal output from the level shift circuit 8, has a waveform shown in (V) of FIG. 2(a). Therefore, since the level-shifted signal 8A and the delayed signal 9A are inverted in magnitude when the test signal is applied, by comparing these two signals in the comparison circuit 10, (III) in FIG. 2(a) is obtained. The output signal 7 of the input signal tracking type comparison circuit shown in FIG.
+ signal output) can be obtained. The magnitude relationship between the delayed signal 9A and the level-shifted signal 8A changes not only when the test signal is applied, but also at the convex and concave portions of the current detection signal, as shown in (V) in FIG. 2(a). be. Therefore, in this respect as well, the input signal tracking type comparison circuit 6
Outputs logic II II I+ signal. In this way, since the input signal tracking type comparison circuit 6 outputs the logic rr I I+ signal even when the test signal is applied, it is necessary to extract only the response to the test signal application. A window circuit 12 and a digital comparison circuit 13 are provided for this purpose. The window circuit 12 is shown in FIG. 2(a) (
When a test signal 11A is input as shown in n), a window signal 12A is output after a certain period of time. A digital comparison circuit 13A performs a logical product of this window signal 12A and the output signal 7 of the input signal tracking type comparison circuit, thereby obtaining a response signal 13A shown in (d) of FIG. 2(a). In other words,
test signal]. Apply IA, active circuit 3 and electromagnetic equipment 2
If it is healthy, a response signal 13A shown in (I) of FIG. 2(a) can be obtained.

Next, we will discuss the first case where the drive circuit 3 fails in the closed state.
This will be explained using the figure and FIG. 2(b).

If the drive circuit 3 fails to close, the drive circuit 3 will not open even if the test signal 11A is applied, so the current detection signal 5 detected by the resistor 4 will be at (V) in FIG. 2(b). )become that way. As a result, the level-shifted signal 8A and the delayed signal 9A become as shown in (V) of FIG. 2(b). That is, when the test signal is applied, the magnitude relationship between the signal levels of the level-shifted signal 8A and the delayed signal 9A does not change. Therefore, the output signal 7 of the input signal tracking type comparison circuit becomes as shown in (III) of FIG. 2(b),
Digital comparison circuit 1 performs logical product with window signal 12A
3, the response signal 11 12 shown in (1) of FIG. 2(b) is obtained. In other words, if the drive circuit 3 fails in the closed state, no response signal can be obtained when the test signal is applied, and from this it can be determined that there is a failure. This determination is executed by the failure determination circuit 14A. This circuit can be realized, for example, by the circuit configuration shown in FIG.

The failure determination circuit 14A is basically the pulse oscillation circuit 1.
4A1. Counter 14A2 and flip-flop circuit 1
4A3 and a fault indicator 14A4, the flip-flop circuit 14A2 is connected to a power supply 14A6,
It is reset by a reset circuit 14A5 connected to a resistor 14A7 and a switch 14A8.

The counter 14A2 counts the number of pulse signals output from the pulse oscillation circuit 14A1, and the response signal]. 3
A is input to the reset terminal 14A9 to reset it. The period of the pulse signal of the pulse oscillation circuit 14A1 is set to be longer than the period of the response signal (pulse-like signal of logic It I I+) obtained by applying the test signal when the drive circuit 3 and the electromagnetic device 2 are healthy. It is determined in advance. In other words, when the drive circuit circuit 3 and the electromagnetic equipment are normal, the counter 14A
2 means that the pulses output from the pulse oscillation circuit 14A1 are not counted.

If the oscillation circuit 3 fails to close, a response signal to the application of the test signal cannot be obtained, and a signal of logic "1" is input to the reset terminal 14A9 of the counter 14A2, resulting in a count mode, and the pulse oscillation circuit 14A
Count the number of pulses from 1. In FIG. 5, when the count value reaches 4, the flip-flop 14A3
is operated to give a failure indication signal to the failure indicator 14A4 to indicate the failure. As shown in FIG. 5, the counter 14A2
, and when the count value reaches 4, flip
The reason why the flop 14A3 was activated was to provide even more reliable information that the movable circuit 3 had failed.
The value of this count is arbitrary.

Next, a description will be given of detection of a failure when the drive circuit 3 fails in an open state, or when the excitation coil of the electromagnetic device 2 is disconnected, or when its connector has poor contact.

All of these failures occur when current does not flow to the electromagnetic device 2. The operating waveforms of each part in this case are as shown in FIG.

As shown in FIG. 7 (II), the test signal 11A is at logic t.
t i n In other words, a failure in which current does not flow to the electromagnetic device 2 is detected when the logic N Q I+ pulse signal is not applied. However, FIG. 6 shows operating waveforms in a normal state, and FIG. 7 shows operating waveforms in a case where a failure occurs.

First, in FIG. 6, the test signal 11A is at the logic LL level.
When I I+, the current detection signal 5 obtained thereby becomes as shown in FIG. 6(m). As a result, the level-shifted signal 8A and the delayed signal 9A are respectively shown in FIG.
It becomes like I[I). Therefore, each time the magnitude relationship between these signals changes, the signal shown in FIG. 6(1) is output from the input signal tracking type comparison/determination circuit 6. This signal is the 8th
It is input to the failure determination circuit 1.4B in the figure. This failure determination circuit 14B has the same structure as the failure determination circuit 14A shown in FIG. 5, except for the input signal and the pulse oscillation circuit 14B1. Specifically, first, the input signal is the output signal 7 of the input signal tracking type comparison circuit, and this is logically inverted by the inverting circuit 14B10, and the counter is reset 14B.
9 is entered. Next, unlike the case of pulse oscillation circuit 14A, the oscillation period of pulse oscillation circuit 14B] is set longer than the pulse output period of the signal shown in FIG.
It is set shorter than the application period of the pulse signal in the test signal shown in (IV) of ) or (IV) of (b).

With this configuration, similarly to 14A, if the signal shown in FIG. 6 (1) is input as the input signal, this becomes the reset signal for the counter 14B2, so that the pulses from the pulse oscillation circuit 1481 are counted. Therefore, flip-flop 14B3 does not operate. In other words, it can be determined that the electromagnetic device 2 and the drive circuit 3 are normal. Note that the reset circuit 14A5 includes a power supply 14B6 and a resistor 14 as in FIG.
B17 and switch 1488.

Next, using FIG. 7, we will explain the operation when a failure occurs in which no current flows in the electromagnetic device 2.

The test signal 11A is logic ``↓'' as shown in Figure 7 (II).
''. When the current stops flowing through the electromagnetic device 2, the current detection signal becomes as shown in FIG. 7(m).

In contrast, the level-shifted signal 8A and the delayed signal 9A
are as shown in Fig. 7(m). As a result, the output signal 7 of the input signal tracking type comparison circuit becomes a logic LL I I+ signal as shown in FIG. 7(1). Therefore, in the failure determination circuit 14B, the logic "O" signal is inputted to the reset terminal 14B9 of the counter 14B2 by the inverting circuit 1.4810, so the counter 14B2 becomes the count mode and the pulse oscillation circuit 14B1 outputs the signal. Count the pulses. When this value becomes 4, flip-flop 14
B3 is operated to output a failure display signal to the failure indicator 14B4. In this way, an open failure in the electromagnetic device 2 or the drive circuit is determined and displayed.

The specific circuit configuration of the input signal tracking type comparison circuit 6 described above will be described below.

A specific example is shown in FIG. The comparator circuit 9 consists of an l-order filter consisting of a resistor 91 and a capacitor 92, and the level shift circuit consists of a diode 81, a resistor 82, and a power supply 83. This power source 83 becomes a voltage source of negative polarity when the diode 81 and resistor 83 are connected in this way. In other words, this is to apply to the comparator circuit 10 a voltage that is lower than the input signal by the forward drop voltage Vf of the diode 8l.

Note that the output of the level shift circuit 8 may be connected to the plus side input terminal of the comparison circuit, and the output of the delay circuit 9 may be connected to the minus input terminal of the comparison circuit 10.

However, in this case, although the signal output from the comparator circuit 10 is inverted in logic from the output signal in the case of FIG. 3, the function of the input signal following type comparator circuit is the same. Further, the delay circuit may be another n-order type filter.

FIG. 4 shows another embodiment of the input signal tracking type comparison circuit 6, and this may be used as the input signal tracking type comparison circuit 6 of FIG.

The input signal tracking type comparator circuit 6 in FIG. The output signal of the level shift circuit is connected to the positive input terminal of the comparator circuit 10. The operating waveforms are (III) to (V) in FIG. 2(a).
) is shown in Figure 9 in comparison. The current detection signal 5 obtained for the test signal 11 is as shown in FIG. 9 (III). Therefore, the delayed signal 9A becomes as shown in FIG. 9 (III). The level shift circuit 8 is different from the case shown in FIG. 1 in that it outputs a signal that is a certain level higher than the input signal of the level shift circuit. Therefore, the level-shifted signal 8A becomes as shown in FIG. 9(m). Since the comparison circuit 10 receives the input signal and the level-shifted signal 8A, the signal shown in FIG. 9(I) is output. In other words,
The same waveform as (III) in FIG. 2(a) can be output from this input signal tracking type comparison circuit 6.

A specific circuit configuration of this input signal tracking type comparison circuit 6 is shown in FIG. As in FIG. 3, the delay circuit 9 consists of a primary filter consisting of a resistor 9l and a capacitor 92, and the level shift circuit has a diode 81, a resistor 82, and a power supply 84 as a positive power source. This power supply differs from that in FIG. 3 and is of positive polarity. By configuring the level shift circuit in this way, the forward drop voltage V of the diode 81 is reduced with respect to the input signal of the circuit 8, that is, the delayed signal 9A.
A voltage higher by f can be applied to the comparator circuit 10.

By the way, the forward drop voltage Vr of the diode in FIG. 3 and this circuit is given by the following equation.

However, −19 The relationship between Vf and If in the above equation is illustrated in FIG. 11. In other words, if the point where the forward current reaches a certain value is defined as the operating point A, then at this point, Vf remains approximately constant even if ir changes. Therefore, Fig. 3 and 1
By configuring as shown in FIG. 0, a level-shifted signal can be obtained.

In FIG. 3 and FIG. 1O, it is possible to use a resistor instead of the diode, but in this case, it is possible to shift the level by the voltage obtained by the resistance ratio between the resistor and the resistor 82. be. However, when the voltage level of the input signal is high and low, the level shift 1
The ratio of the levels shifted to ~ is the same, but the magnitude of the level shifted is different. In other words, when the input signal is small,
The amount of level shift is small, and when the input signal is large, the amount of level shift becomes large. As a result, Figure 2 (
a) Alternatively, in FIG. 9, when the test signal is applied, the inversion period of the magnitude relationship between the two signals input to the comparison circuit IO becomes shorter. In other words, the period of the response pulse of the output signal from this comparison circuit is only 201 times shorter.

Next, a method will be described in which the current flowing through the drive circuit is detected by other detection means instead of the resistor 4 in FIG.

When detecting current using a resistor, the resistor is directly inserted into the drive circuit of the electromagnetic device, so there is a problem that failure of the resistor may lower the operating rate of the system. To solve this problem, it is desirable to detect current without contact.

Therefore, as shown in Fig. 12, the current transformer 15
Using this, the magnetic field generated by the flow of current can be extracted as a voltage signal by the current transformer 15. The output signal of this current transformer 15 is input to the input signal tracking type comparison circuit 6 described above. To Karen 1: Since the transformer is a so-called AC coupling element, the DC component is cut off. For this reason, for example, as shown in Fig. 3 (I), the test signal 11A is
(pulse signal) is applied to the drive circuit, this results in
In the current detection signal obtained by the current transformer 15, the current off period is shifted to the positive side. This is because the current transformer is an AC coupling element, but the input signal tracking type comparison circuit is configured to detect changes in current, and as shown in Figures 3 and 10. , the level shift circuit is designed to be able to shift by a fixed level even if the level of the input signal changes, so the input signal tracking type comparison circuit 6 is configured such that the input signal is shifted as shown in FIG. 13(n).
Even if the current detection signal is as follows, the response signal when the current is off can be accurately detected.

Furthermore, in FIGS. 1 and 12, it goes without saying that if the level of the current detection signal is small, an amplifier circuit for amplifying the signal level may be provided at the input stage of the input signal tracking type comparison circuit. It is.

Also in FIG. 13, the test signal is applied when the current flowing through the electromagnetic device becomes zero, and this is for the following reason.

For example, as shown in FIG. 14, if a pulse signal is applied as the test signal 11 when the current flowing through the electromagnetic device 2 is at its maximum, a large noise voltage will be generated in the power supply voltage. This noise voltage E. is given by the following equation.

d. The switching time of the drive circuit is considered to be several mg to several μs, although it depends on the elements used, so En ends up being a very large value. In particular, when driving large electromagnetic equipment, the current is large, so En becomes extremely high. Therefore, a new protection circuit for controlling this noise voltage is required, which increases the amount of hardware, and there is a problem in that the reliability of the system decreases due to failure of the protection circuit itself.

In order to solve this problem, control should be performed so that i becomes zero in equation (2). For this purpose, electromagnetic equipment 2
It suffices to detect the current flowing through the circuit and apply the test 1 signal when this current becomes zero, and the structure is as shown in FIG. In this figure, a current is detected by a current transformer 15, and the result is sent to a phase detection circuit 1.
Enter 6. The phase detection circuit 16 outputs a command signal for outputting the test signal 11A when the current becomes zero to the test signal generation circuit 1l. With the above configuration, it is possible to apply a test signal without generating noise voltage.

Here, if the switch making up the active circuit has a mechanical contact structure such as a relay or contactor, the delay in operation may be several times. If this delay time becomes a problem, the drive circuit may be replaced with a semiconductor switching element.

Possible semiconductor switching elements include transistors, thyristors, and the like. In particular, in some cases, the following effects can be obtained using a thyristor.

As shown in FIG. 16, the drive circuit is controlled by the bidirectional thyristor 3, the phase of the power supply voltage is detected by the phase detection circuit 16, and the test signal 11A is output when the power supply voltage becomes zero. A command signal for this purpose is output to the test signal generation circuit 11. The test signal generation circuit outputs a pulse signal having a time width longer than the pulse width of the test signal described above (this pulse width is determined in advance), taking into account the phase difference between voltage and current.

Generally, a thyristor is switched off if there is no gate signal when the current is below the holding current, so in this case, when the current flowing through the bidirectional thyristor 3 is below the holding current, the thyristor is switched off. Then, when the test signal becomes logic rr I I+, the switch is turned on again.
Turns on. As a result, as shown in FIG. 17 (III), the current of the electromagnetic device in response to the test signal 11A is detected by the current transformer 15.

In the case of FIG. 15, the phase was detected using the output signal of the current 1 Herance 5. For this reason, as the application period of the test signal becomes shorter, the level of the signal changes as shown in Figure 13 (+1), so it is difficult to detect the phase point where the current flowing through the electromagnetic device becomes zero. However, if the voltage is detected, this problem will not occur and the application timing of the test signal 11A can be determined with a simple circuit.

FIG. 18 is an example in which the present invention is applied to a redundant control and protection device with a diagnostic function disclosed in Japanese Patent Application No. 62-226370.

However, the output circuit is intended for the power circuit shown in the control protection device of Japanese Patent Application No. 62-4834.

The scram solenoid valve 2 has two excitation coils, and the test signals according to the embodiment described above are separately applied to the excitation coils.

Then, a failure diagnosis is performed for each exciting coil. This is known as a surveillance test. An example of such a surveillance test is shown in FIG.

This circuit structure is basically the same as that shown in FIG.
The series-parallel circuits SI1 to SI18 constitute a fluctuating circuit. However, the coil LO in the output circuit-1 is a current balancing coil for the thyristor parallel circuit. In addition, current lances CT1 to CT4 are provided to detect the current flowing through the parallel circuit structure in the output circuit, and input signals a to d of output circuit-1 and CTI to CT4
The current detection signal obtained by
1 or a failure of the scram solenoid valve 2 can be detected. This pattern comparison is described in Japanese Patent Application No. 62-226370. In addition, since the window circuit 12 has four test signals a to d, the OR circuit 17 calculates the logical sum of these signals and inputs the output signal.
Input signal tracking type comparison circuits 61 to 64 for test signals
is obtained by digital comparison circuits 131-134.

By configuring as above, although not shown, 4
This makes it possible to accurately diagnose test signals that are output non-periodically from two diagnostic circuits. When a test signal is applied non-periodically, the output signal of each current transformer may become as shown in FIG. The comparison circuit allows the system to be diagnosed without any problems.

〔Effect of the invention〕

As described above, the present invention applies a test signal with a time width in which the electromagnetic equipment does not operate to the drive circuit, applies the current flowing in the drive circuit to the input signal tracking type comparison circuit, and compares the test signal with the test signal. By comparing the output signal of the input signal tracking type comparison circuit, it is possible to detect slight current changes caused by the application of the test signal, and it is possible to detect failures in the drive circuit or electromagnetic equipment without operating the electromagnetic equipment. can be detected. In addition, it is possible to use a current transformer as the current detection means to detect the current without contact and perform diagnosis in the same way, so the reliability of the system can be increased and the engineering value is extremely high. expensive.

[Brief explanation of drawings]

Fig. 1 is an embodiment of the present invention, Fig. 2 is its time chart, Figs. 3, 4, and 10 are embodiments of the comparison circuit of the present invention, and Figs. 5 and 8 are failures. Embodiment diagram of the determination circuit, FIGS. 6, 7, and 9 are time charts of this embodiment, FIG. 11 is a diode characteristic diagram, FIGS. 12, 15,
6 is a diagram showing another embodiment of the present invention, FIGS. 13, 14, and 17 are time charts of each embodiment, and FIG. 18 is a diagram of an application example of the present invention. 2... Electromagnetic equipment, 8... Level shift h circuit, 3...
- Postal circuit, 9...Delay circuit, 6...Input signal follow-up comparison circuit, IIA...Test signal, 13...Digital comparison circuit.

Claims (1)

[Claims] 1. An apparatus for diagnosing electromagnetic equipment and the drive circuit by applying a test signal to the drive circuit of the electromagnetic equipment, comprising: means for applying a test signal to the drive circuit during a time period in which the electromagnetic equipment does not operate; , current detection means for detecting the current flowing in the drive circuit, level shift means for inputting the detection signal, delay means for inputting the detection signal, and output signals of each of the level shift means and the delay means. 1. An online diagnostic device for electromagnetic equipment and its drive circuit, comprising a comparison means for comparing the test signal and an output signal of the comparison means when the test signal is applied. 2. A device for diagnosing an electromagnetic device and the drive circuit by applying a test signal to the drive circuit of the electromagnetic device, comprising means for applying a test signal to the drive circuit with a time width during which the electromagnetic device does not operate, and current detection means for detecting the current flowing through the circuit, delay means for inputting the detection signal, level shift means for inputting the output of the delay means, and comparison means for comparing the detection signal with the output of the level shift means. and means for comparing the test signal with the output signal of the comparison means when the test signal is applied. 3. In a device that applies a test signal to a drive circuit of an electromagnetic device to diagnose the electromagnetic device and the drive circuit, a test signal having a time width in which the electromagnetic device does not operate in synchronization with the power supply voltage applied to the drive circuit. means for applying the voltage to the drive circuit;
current detection means for detecting a current flowing in the drive circuit;
level shift means for inputting the detection signal; delay means for inputting the detection signal; comparison means for comparing the respective output signals of the level shift means and the delay means; An online diagnostic device for electromagnetic equipment and its drive circuit, comprising means for comparing the output signal of the comparison means with the output signal of the comparison means. 4. The electromagnetic device according to claims 1 to 4 is a scram solenoid valve having two excitation coils, and an online diagnostic device for the electromagnetic device and its drive circuit. 5. The above level shift amount and delay amount are determined by the output of the level shift means when a detection signal is input when a test signal is applied;
4. The online diagnostic device according to claim 1, wherein the output of the delay means for inputting the detection signal when the test signal is applied is set to have a waveform that crosses each other. 6. The delay level shift amount obtained by combining the above level shift amount and delay amount is the detection signal when the test signal is applied,
3. The online diagnostic device according to claim 2, wherein the detection signals taken out through the delay means and the level shift means are set to have waveforms that cross each other.