JPS6310424A - Operation time detector for breaker or the like - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to an improvement in a device for detecting operating time of a circuit breaker or the like.

[Conventional technology] FIG. 3 shows an operating circuit of a conventional operating time detection device.

In the figure, the circuit breaker section (9) is coupled to the operating mechanism (6) via an operating link (8), which is not shown. The operating coil (4) is connected to the operating mechanism (6) via a transmission mechanism (7), which is not shown. Also, pallet contacts (
5) is a b contact switch that operates in conjunction with the operating mechanism (6). ! ! Switch (2) to operate when disconnecting
) is connected to one end (1) of a DC power source.

The other end of the switch (2) is connected to the other end (19) of the power source via the operating coil (4) and pallet contact (5) by a conductor (21) inserted through the current transformer (11), and is connected to the operating circuit ( 14).

Next, the operation will be explained. When the switch (2) is closed to perform a cutoff operation, a direct current (IC
) flows in the direction shown by arrow A, for example, and the operating coil (4)
is excited to operate the control I'Pa mechanism (6). The time point is indicated by time point (tl) in the timing chart of FIG.

Control machine v! Opening of the circuit breaker (9) is started at time (t2) after the time required for transmission of the operation link (8) from the operation (6). The operating mechanism (6) interrupts the circuit breaker (4) at time (t3), opens the pallet contact (5) to open the operating circuit, and ends the interrupting operation. The current (ic) is detected by a current transformer (11), and the detection signal is input to a timer (15). Timer (15)
The arithmetic unit whose illustration is omitted is shown in FIG. 4(b).
The time between t2) and t3 is calculated and displayed on the display (16) as the operating time of the circuit breaker, etc.

[Problems to be Solved by the Invention] In the conventional circuit breaker operation time detection device described above, when the current conduction time of the operation circuit becomes longer due to a malfunction in the operation mechanism, the current transformer (11) will cause DC saturation. Put it away.

As a result, correct current detection may not be possible during the next operation. In such a case, in order to eliminate the magnetic saturation of the current transformer (11), it is necessary to remove the current transformer (11) and remove the residual magnetic flux.

[Means for solving the problem] The operating time detection device for a circuit breaker, etc. according to the present invention detects the operation time of a current transformer when the operation time of the operation circuit exceeds a predetermined time. It is configured so that a current equal to and opposite in polarity to the operating current is passed through the operating current.

[Operation] The magnetic saturation of the current transformer is canceled by the current of opposite polarity and the normal state is restored.

[Example] Fig. 1 shows the operating device 15 (14) of the circuit breaker operation time detection device of the present invention. machine t*(6)
is combined with The operating coil (4) is connected to the operating afJ (6) via a transmission mechanism section (7), which is not shown. In addition, the pallet contact (5) is a B contact switch that is linked to the operating mechanism (6). One end of the switch (2) that is operated when performing a 0g disconnection operation is one end of the DC power supply (1
)It is connected to the. The first conductor (21) connected to the other end of the switch (2) passes through the current transformer (11), passes through the operating coil (4) and the pallet contact (5), and connects to the other end of the power supply, the ground ( 19).

The output of the current transformer (11) is input to a timer device (15). The timer device (15) measures the time during which the current (IC) flows through the operating circuit (14) and displays the value on the display (16). The current transformer (11) has a second conductor (1) connected at one end to the power supply (1) via a DC saturation canceler (17).
20) is inserted through it, and the other end is connected to ground (19). The direction of insertion of the conducting wire (20) into the current transformer (11) is such that the direction of current flowing through the conducting wire (20) is opposite to the direction of current flowing through the conducting wire (21). The timer device (15) has an arithmetic device (not shown), and calculates the energization time (T+) of the current (ic).
When the value exceeds a predetermined value, a signal is output to a DC saturation eliminating device (17). .

Next, the operation will be explained. When the switch (2) is closed to perform a cutoff operation, a direct current (IC) flows through the operating circuit (14), energizing the operating coil (4) and operating the operating mechanism (6) - at that point. The opening of the cutoff part (9) starts at time (t2) after the time required for transmission of the operation of the operation link (8) from the operation of the operation mechanism (6), which is shown at time (1+) in the timing chart of FIG. 2. be done. The operating mechanism (6) interrupts the interrupter (9) at time (t3), opens the pallet contact (5), and closes the operating circuit (14).
) to complete the shutoff operation.

The current (ic) is detected by the current transformer (11), and the detection signal is calculated by the arithmetic unit of the timer (15) to determine the current conduction time (T1), which is the time between time (t2) and (t3).
) is calculated and the zero energization time (1) is displayed on the display (16).

For example, due to a malfunction in the operating unit IN (6), the energization time (T+
) becomes longer than a predetermined value preset in the timer (15), the timer (5) turns off the cut-off part (9).
After completion of the cutoff, an activation signal is given to the DC saturation elimination device (17) at time (t4). The DC saturation canceling device (17) is activated by the activation signal and the AC converter (11) is activated.
Connect the conducting wire (20) to the DC power source (1). As a result, the DC current flows in the current transformer (11) in the direction shown by the arrow (B), canceling out the DC saturation caused by the current in the direction shown by the arrow (A) during the interrupting operation. The current value when the DC saturation canceling device (17) operates is set to be the same as the current (ic). Also, energization time T2 (ts-t4)
is controlled by the arithmetic unit in the timer (15) so that it is the same as the energization time T1 when DC saturation occurs.

Note that the v1 operation time detection device of the present invention can be applied not only to circuit breakers but also to disconnecting switches and grounding devices.

[Effects of the Invention] According to this invention, DC saturation of the current transformer of the operating time measuring device can be automatically resolved while the current transformer is attached to the operating circuit, so there is no need to remove it, and therefore the residual magnetic flux can be reduced. No removal work is required.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram showing an operating circuit of an embodiment of the operating time detection device of the present invention, FIG. 2 is a timing chart showing the operation of this embodiment, and FIG. 3 is a circuit diagram of a conventional operating time detection device. FIG. 4 is a circuit diagram showing the operating circuit, and is a timing chart showing the operation of the conventional example shown in FIG. 11: AC generator 14: Operation circuit 15: Timer 17: DC saturation canceling device 20; Second conducting wire Note that the same reference numerals in each figure indicate the same or corresponding parts. Agent Masuo Oiwa Figure 1 2: Switch 4: Seshii Ai'l. 5: Ha・I, 7to side point 6: Sot fraud 79 fable・7T tool 8 ・〈:1 memiike 3' non 7 9: Lq'tk 4P 12: Out 77 Uchiko 1S: Ri, timer 16-display A 17, Xiankyo/Princess, +I disassembly device 0: Second conductor Figure 2 Figure 3, 14 Kaya 4 x Procedural amendment (voluntary)

Claims (2)

[Claims] (1) Based on the current transformer installed to detect the current of the operating circuit, the second conductor inserted through the current transformer, and the detection output of the current transformer, the current conduction time exceeds a predetermined time. An operating time detection device for a circuit breaker, etc., comprising: switching means for causing a current of opposite polarity and the same value as the current of the operating circuit to flow through the second conductor when the current is applied. (2) The switch means includes a timer device that compares and calculates the energization time with a preset predetermined time and outputs an output signal when the energization time exceeds the predetermined time, and a timer device that outputs an output signal when the energization time exceeds the predetermined time; An operating time detection device for a circuit breaker or the like according to claim 1, comprising a DC saturation eliminating device for controlling the flowing current.