JP2014084215A - Elevator monitoring equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide elevator monitoring equipment that can maintain the operation of an elevator in a normal state, even if power failure occurs.SOLUTION: The elevator monitoring equipment includes: a power failure detection device 8 for detecting interrupt of a power supply from an AC commercial power supply 1; electric storage equipment 6 for storing electric power for use in substitution for the AC commercial power supply 1, when the interrupt of the power supply is detected by the power failure detection device 8; an elevator control device 3 for controlling the operation of an elevator; a power failure rescue operation device 7 for performing rescue operation at power failure; and a monitoring part 10 for detecting abnormal conditions of the elevator. The elevator monitoring equipment also includes: a timer 11A for measuring the time elapsed after the interrupt of the power supply is detected by the power failure detection device 8; and an elevator power source switching device 4 for switching a power supply source for supplying power to the elevator control device 3 from the AC commercial power supply 1 to the electric storage equipment 6 when the time measured by the timer 11A reaches a predetermined time T.

Description

  The present invention relates to an elevator monitoring device that monitors an abnormality of an elevator, and more particularly to an elevator monitoring device that is suitable for operating an elevator during a power failure.

  Conventionally, an elevator installed in a building is operated mainly by supplying power from an AC commercial power source to a control circuit or a drive circuit, but when the power source from this AC commercial power source is interrupted by a power failure, Even if the running car stops between the floors where the doors do not normally open, by moving the car to the nearest floor with the power of the storage battery provided in advance, the door is opened in the car Rescue operation during a power failure to rescue the trapped passengers. For example, an emergency automatic landing device for an AC elevator shown in Patent Document 1 is known as one of conventional techniques related to a power failure rescue operation device that prevents such confinement during a power failure.

  In addition to the elevator, the building is provided with facilities such as water supply, lighting, security devices, etc., and these facilities are also supplied with power from an AC commercial power source in the same manner as the elevator. Therefore, if the AC commercial power supply is cut off, the building equipment cannot be used. Therefore, even in such a case, the power supply of the building equipment including the elevator can be secured to some extent. A power storage facility is provided as a supply source, and power from the power storage facility is used for building facilities until the power from the AC commercial power source is restored.

JP-A-2-198994

  In an elevator provided with a rescue operation device at the time of a power failure such as an emergency emergency landing device for an AC elevator according to the prior art disclosed in Patent Document 1, when a power failure occurs and the power from the AC commercial power source is cut off As described above, the rescue operation during a power failure is performed by the rescue operation device during a power failure using the power of the storage battery. At this time, when power is supplied from the power storage equipment to the building equipment including the elevator, the rescue operation device during a power failure detects the interruption of the power from the AC commercial power supply and performs the rescue operation during a power failure. Regardless, since the power supply is received redundantly from the power storage equipment in addition to the storage battery, there is a risk of an emergency stop resulting in a malfunction.

  The present invention has been made based on the actual situation of the prior art as described above, and an object thereof is to provide an elevator monitoring apparatus capable of maintaining the operation of the elevator normally even if a power failure occurs.

  In order to achieve the above object, an elevator monitoring apparatus according to the present invention includes an AC commercial power source that supplies power to a building facility including the elevator, and a power failure detection that detects an interruption of the power source supplied by the AC commercial power source. A power storage device for storing power to be used in place of the AC commercial power supply when the power failure from the AC commercial power supply is detected by the power failure detection device, and an elevator control device for controlling the operation of the elevator And a power failure rescue operation device that performs a power failure rescue operation that moves the elevator car to the nearest floor when a power supply to the elevator control device is detected, and is connected to the elevator control device. And a monitoring unit for detecting an abnormality of the elevator, wherein the AC quotient is detected by the power failure detection device. A timer unit for measuring the time elapsed since the detection of the power cutoff from the power source, and a power supply source to be supplied to the elevator control device when the time measured by the timer unit reaches a predetermined time And a switching unit for switching from the AC commercial power source to the power storage facility.

  According to the elevator monitoring apparatus of the present invention, the operation of the elevator can be kept normal even if a power failure occurs. Problems, configurations, and effects other than those described above will become apparent from the following description of embodiments.

It is a figure which shows the structure of one Embodiment of the monitoring apparatus of the elevator which concerns on this invention. It is a flowchart explaining operation | movement of this embodiment.

  EMBODIMENT OF THE INVENTION Hereinafter, the form for implementing the elevator monitoring apparatus which concerns on this invention is demonstrated based on figures.

  One embodiment of an elevator monitoring apparatus according to the present invention includes an AC commercial power source 1 that supplies power to building facilities (not shown) such as waterworks, lighting, and security devices including an elevator, as shown in FIG. And a distribution board 2 that is provided in the site of the building and distributes the power supplied by the AC commercial power supply 1. The AC commercial power source 1 is a three-phase AC power source that transmits power from a power company, for example, and outputs an AC voltage having a constant frequency to a connected device.

  The distribution board 2 has, for example, a primary side connected to the AC commercial power supply 1 and is connected to the primary side switch 2a that controls the connection state of the AC commercial power supply 1 by opening and closing, and the secondary side is connected to each device of the building facility. And a plurality of secondary side switches 2b to 2n for controlling the connection state of each device by opening and closing.

  The present embodiment includes a power failure detection device 8 that detects the interruption of the power supplied from the AC commercial power source 1, and this power failure detection device 8 is stored in the distribution board 2, for example. A power failure detection signal is output when power interruption from the AC commercial power source 1 is detected due to a power failure or opening of the primary side switch 2a, and AC commercial power is restored by returning the AC commercial power source 1 or closing the primary side switch 2a. When power recovery from the power source 1 is detected, a power recovery detection signal is output.

  In the present embodiment, the elevator control device 3 for controlling the operation of the elevator and the elevator car (not shown) on the nearest floor when the interruption of the power supplied to the elevator control device 3 is detected. A power failure rescue operation device 7 that performs a power failure rescue operation to be moved to a power failure, and a storage battery (not shown) that stores electric power used in the power failure rescue operation by the power failure rescue operation device 7 are provided.

  Therefore, even if the power supplied from the AC commercial power supply 1 to the elevator control device 3 is cut off and the traveling car stops between the floors where the doors (not shown) normally do not open, it is rescued in the event of a power failure When the driving device 7 performs the rescue operation at the time of a power failure by the power of the storage battery, the stopped car starts to move to the nearest floor and the door is opened.

  In the present embodiment, when the interruption of the power supply from the AC commercial power source 1 is detected by the power failure detection device 8, the power storage facility 6 that stores power to be used instead of the AC commercial power source 1 and the elevator control device 3 are supplied. Elevator power source switching device 4 that switches the power supply source from AC commercial power source 1 to power storage facility 6, and secondary side switch 2n, power storage facility 6, among secondary side switches 2b to 2n of distribution board 2, and Connected to the elevator power supply switching device 4, the alternating current transmitted from the AC commercial power supply 1 is converted into direct current to charge the power storage facility 6, and the direct current taken out from the power storage facility 6 is converted into alternating current to convert the elevator power supply switching device 4. And a power converter 5 that outputs to the power source.

  The above-described power storage facility 6 that supplies power in the event of an emergency includes, for example, a plurality of storage batteries, and is installed in the site of the building in the same manner as the distribution board 2. Then, when the power failure detection device 8 detects the interruption of the power supply from the AC commercial power source 1, the power storage facility 6 supplies power to building equipment such as water supply, lighting, and security device in addition to the elevator control device 3. Like to do.

  The present embodiment includes a monitoring unit 10 that is connected to the elevator control device 3 and detects an abnormality of the elevator. The monitoring unit 10 includes, for example, an elevator control device 3, an elevator power switching device 4, a power conversion device 5, And an input / output device 12 that is connected to the power failure detection device 8 and inputs / outputs various signals to / from these devices, and a control unit 11 that performs a corresponding processing operation on the signal input by the input / output device 12. And a storage device 13 for storing at least an operation program executed by the control unit 11.

  Here, the monitoring unit 10 is connected via a communication line to a monitoring center that remotely monitors the elevator (not shown), for example, and the control unit 11 is connected to the building facility including the elevator via the input / output device 12. When an abnormality is detected, the monitoring center is notified that an abnormality has occurred in the building equipment. For example, when the monitoring center receives a notification from the monitoring unit 10 that an abnormality has occurred in a building facility, the monitoring center dispatches a worker who performs a restoration operation of the building facility to the building.

  In this embodiment, the power failure detection device 8 measures the time elapsed since the interruption of the power supply from the AC commercial power supply 1 is detected, for example, a timer 11A, and the time measured by the timer 11A is a predetermined first time. A switching unit that switches the supply source of power to be supplied to the elevator control device 3 from the AC commercial power source 1 to the power storage facility 6 when 1 hour T is reached. It consists of device 4.

  Specifically, the timer 11A is provided in, for example, the monitoring unit 10 and is connected to the control unit 11. The timer 11A measures time when the control unit 11 inputs a power failure detection signal via the input / output device 12. When the measured time reaches a predetermined first time T, a progress signal notifying that is output to the control unit 11.

  When the progress signal is input from the timer 11A, the control unit 11 outputs a discharge switching command signal for converting the direct current extracted from the power storage facility 6 to alternating current to the power conversion device 5 and supplies power to the elevator control device 3 Is supplied to the elevator power switching device 4 at the time of a power failure to switch the supply source from the AC commercial power source 1 to the power storage facility 6.

  Therefore, when the power conversion device 5 receives the discharge switching command signal from the control unit 11 of the monitoring unit 10, the power conversion device 5 converts the direct current extracted from the power storage facility 6 into alternating current and outputs the alternating current to the elevator power supply switching device 4. Further, the elevator power supply switching device 4 is connected to the elevator control device 3 on the output side, for example, so that the connection state on the input side is changed to the switch 2b or the power switching device 5 among the switches 2b to 2n of the distribution board 2. It has the power supply switching switch 4a switched to.

  The power switching switch 4a opens, for example, when a power failure switching command signal is input from the control unit 11 of the monitoring unit 10 to change the connection state on the input side from the switch 2b of the distribution board 2 to the power switching device. 5, and the input side of the power switch 4 a is separated from the switch 2 b of the distribution board 2 and connected to the power switch 5, thereby supplying power from the power storage facility 6 to the elevator controller 3. Is to be done.

  In addition to the above-described discharge switching command signal and power failure switching command signal, the control unit 11 receives signals input from the elevator control device 3, the elevator power switching device 4, the power conversion device 5, and the power failure detection device 8. Accordingly, for example, a power failure operation command signal for switching the operation of the elevator from a normal operation to a stop operation, a suspension command signal for stopping the operation of the elevator, and alternating current transmitted from the AC commercial power supply 1 is converted into direct current to charge the power storage facility 6 Charge switching command signal for performing the operation, normal power switching command signal for switching the supply source of the power supplied to the elevator control device 3 from the power storage facility 6 to the AC commercial power supply 1, and canceling the operation stop state of the elevator to operate the elevator normally The normal operation command signal to be output is output. The elevator control device 3 is configured to output a stop completion signal for notifying that to the control unit 11 of the monitoring unit 10 when the operation of the elevator is stopped.

  Further, in the present embodiment, the predetermined first time T, which is a reference when the timer 11A measures the time and outputs the elapsed signal to the control unit 11, is the power supply supplied to the elevator control device 3, for example. It is set to be longer than the time taken from the detection of the interruption until the operation of the rescue operation apparatus 7 during a power failure is completed.

  Next, operation | movement of one Embodiment of the monitoring apparatus of the elevator which concerns on this invention is demonstrated in detail based on the flowchart of FIG.

  FIG. 2 is a flowchart for explaining the operation of this embodiment.

  In the present embodiment, the elevator control device 3 controls the operation of the elevator so that if the elevator operates normally without any abnormality, the monitoring unit 10 does not detect the abnormality of the elevator. Operation is performed (step (hereinafter referred to as S) 1).

  Next, the power failure detection device 8 confirms the interruption of the power from the AC commercial power source 1 by the power failure of the AC commercial power source 1 or the opening of the primary side switch 2a of the distribution board 2, and the distribution board 2 enters the energized state. It is determined whether or not there is (S2). At this time, if it is determined by the power failure detection device 8 that the distribution board 2 is in the energized state, the power failure rescue operation device 7 supplies power to the elevator control device 3 when the elevator car is traveling. Is checked, that is, whether or not a power failure has occurred in the elevator control device 3 during traveling of the car (S3).

  In step S3, when the power saving rescue operation device 7 confirms that the power failure of the elevator control device 3 during the traveling of the car has not occurred, the elevator control device 3 is in the energized state, so the operation returns to the operation of step S1. Thus, the elevator control device 3 continues the normal operation of the elevator. On the other hand, in step S3, when the power failure rescue operation device 7 confirms that the power failure of the elevator control device 3 during traveling of the car has occurred, the time elapsed since the power failure of the elevator control device 3 occurs is counted. .

  The rescue operation device 7 at the time of a power failure waits until the counted time reaches a predetermined second time, for example, 3 seconds (S4), and when the counted time reaches 3 seconds, the car is placed at a position where the door can be opened. It is determined whether or not has stopped (S5). At this time, if it is determined that the car is not stopped at a position where the door can be opened, the rescue operation device 7 during a power failure performs a rescue operation during a power failure and moves the car to the nearest floor (S6). Return to the operation of step S5.

  On the other hand, in the operation of Step S5, when the rescue operation device 7 during a power failure determines that the car has stopped at a position where the door can be opened, the door is opened and the time elapsed since the door was opened is counted. To do. Then, the rescue operation device 7 at the time of a power failure waits with the door opened until the counted time reaches a predetermined third time, for example, 30 seconds, and when the counted time reaches 30 seconds, the door is closed and the passenger rides. After the car is turned off, the operation of the elevator is stopped (S7), and it is confirmed whether the supply of power to the elevator control device 3 is restored (S8).

  In step S8, when the power failure rescue operation device 7 confirms that the power supply to the elevator control device 3 has been restored, the power failure rescue operation is canceled, and the procedure returns to the operation of step S1 to return the elevator control device 3 to the elevator control. Perform normal operation.

  In step S2, the power failure detection device 8 determines that the distribution board 2 is not energized, or in step S8, the power failure rescue operation device 7 confirms that the power supply to the elevator control device 3 has not been restored. When the power failure is detected, the power failure detection device 8 outputs a power failure detection signal to the monitoring unit 10. And if the control part 11 of the monitoring part 10 inputs the power failure detection signal from the power failure detection apparatus 8 via the input / output device 12, the control part 11 will start the timer 11A and the timer 11A will start measurement of time.

  Here, assuming that the car runs at a speed of 6 meters per minute, the driving time from the position between the floors where the door cannot be opened in step S6 to the nearest floor is half of the floor of the first floor. (1) The number of travels is 1 minute (there are few buildings with a distance between floors of 12m or more).

  Accordingly, the time from when the power failure rescue operation device 7 confirms that the power failure of the elevator control device 3 during the traveling of the car has occurred in step S3 until the elevator operation is stopped in step S7, that is, the elevator control device. 3 is 3 seconds measured in step S4 and between the floors where the door cannot be opened in step S6 after the interruption of the power supply supplied to 3 is detected. 1 minute, which is the driving time from the location of the car to the nearest floor, and a little over 30 seconds from when the car arrives at the nearest floor in step S7 until the elevator operation is stopped. Less time.

  Therefore, in the present embodiment, the above-described predetermined first time T that is a reference when the elapsed time signal is output to the control unit 11 after the timer 11A measures time is set to 2 minutes, for example. Therefore, when the time measured by the timer 11A reaches 2 minutes (S9), the timer 11A outputs an elapsed signal to the control unit 11.

  When the elapsed signal is input from the timer 11 </ b> A, the control unit 11 outputs a discharge switching command signal to the power conversion device 5 and outputs a power failure switching command signal to the elevator power switching device 4. Thereafter, the control unit 11 outputs a power failure operation command signal to the elevator control device 3.

  When the power conversion device 5 receives the discharge switching command signal from the control unit 11 of the monitoring unit 10, the power conversion device 5 converts the direct current extracted from the power storage facility 6 into alternating current and outputs the alternating current to the elevator power supply switching device 4. In addition, when the power supply switching command signal at the time of power failure is input from the control unit 11, the elevator power switching device 4 opens the power switching switch 4 a and supplies power to the elevator control device 3 from the AC commercial power supply 1 to the power storage facility 6. Switch (S10).

  Next, when the elevator control device 3 is supplied with power from the power storage facility 6 via the power conversion device 5 and the elevator power supply switching device 4 and receives a power failure operation command signal from the control unit 11 via the input / output device 12, A preset power outage operation of the elevator is performed (S11). Then, the power failure detection device 8 confirms the power recovery from the AC commercial power supply 1 by returning the AC commercial power supply 1 or closing the primary side switch 2a of the distribution board 2. It is determined whether or not is in a power failure state (S12).

  At this time, when the power failure detection device 8 determines that the distribution board 2 is in a power failure state, the power failure detection device 8 returns to the operation of step S10. On the other hand, if the power failure detection device 8 determines in step S12 that the distribution board 2 is not in a power failure state, it outputs a power recovery detection signal to the control unit 11 of the monitoring unit 10. Next, when the power recovery detection signal is input from the power failure detection device 8 via the input / output device 12, the control unit 11 outputs a suspension command signal to the elevator control device 3 (S13).

  Next, when the elevator control device 3 inputs a stop command signal from the control unit 11 and the car is running, the elevator control apparatus 3 moves the car to the nearest floor where the door can be opened and stops it. The destination floor registration and hall call registration already registered after the car stops at the nearest floor is discarded, the door is opened, and the time elapsed since the door was opened is counted.

  Then, the elevator control device 3 stands by with the door opened until the counted time reaches a predetermined fourth time, for example, 30 seconds. When the counted time reaches 30 seconds, the door is closed and the car is closed. After the lighting is turned off, the operation of the elevator is suspended (S14), and a suspension completion signal is output to the control unit 11 of the monitoring unit 10. The control unit 11 determines whether or not the elevator is in an operation suspension state based on whether or not the suspension completion signal is input from the elevator control device 3 (S15). At this time, when the control unit 11 determines that the elevator is not in the operation suspension state, the control unit 11 returns to the operation of step S14.

  On the other hand, when the control unit 11 determines in step S15 that the elevator is in an operation suspension state, the control unit 11 outputs a charge switching command signal to the power conversion device 5 and at the same time a normal power switching command to the elevator power switching device 4. Output a signal. When the power conversion device 5 receives the charge switching command signal from the control unit 11 of the monitoring unit 10, the power conversion device 5 converts the AC transmitted from the AC commercial power supply 1 through the distribution board 2 to DC and charges the power storage facility 6. .

  When the elevator power switching device 4 receives a normal power switching command signal from the control unit 11, the elevator power switching device 4 is closed to supply power to the elevator control device 3 from the power storage facility 6 to the AC commercial power source 1. Switching (S16). Thereafter, the control unit 11 of the monitoring unit 10 outputs a normal operation command signal to the elevator control device 3 via the input / output device 12. And the elevator control apparatus 3 will perform the normal driving | operation of an elevator, if the normal driving | operation command signal is input via the input / output device 12 from the control part 11, and complete | finishes the operation | movement of this embodiment.

  According to this embodiment configured as described above, the control unit 11 of the monitoring device 10 uses the timer 11A even if the power failure detection device 8 in the distribution board 2 detects the interruption of the power supply from the AC commercial power supply 1. After the measured time reaches a predetermined first time T of 2 minutes, the switch 4a of the elevator power supply switching device 4 is opened, the input side of the switch 4a is connected to the power conversion device 5, and By supplying power to the elevator control device 3 via the power conversion device 5 and the elevator power supply switching device 4, the power storage facility 6 in addition to the storage battery when the rescue operation device 7 during a power failure performs a rescue operation during a power failure. Therefore, it is possible to avoid the redundant supply of power. As a result, it is possible to suppress the emergency stop of the elevator due to a malfunction, so that the operation of the elevator can be kept normal even if a power failure occurs.

  In the present embodiment, the power supply for supplying the elevator control device 3 with a predetermined first time T, which is a reference when the timer 11A measures the time and outputs the elapsed signal to the control unit 11, is detected. Since the start of the supply of power from the power storage facility 6 to the elevator control device 3 is sufficiently delayed by setting it to 2 minutes of the time required for the operation of the rescue operation device 7 at the time of power failure to be completed. Thus, the elevator can be operated smoothly while preventing the malfunction of the elevator. Thereby, the stability of the operation | movement of the elevator at the time of a power failure can be improved.

  Further, in the present embodiment, the control unit 11 of the monitoring device 10 causes the stop command signal to be sent to the elevator control device 3 that is performing the power failure operation of the elevator even when the supply of power from the AC commercial power supply 1 is resumed. Is output to stop the operation of the elevator, and then power is supplied from the AC commercial power supply 1 to the elevator control device 3 via the distribution board 2 and the elevator power supply switching device 4, and the elevator control device 3 is normally connected to the elevator. Since the operation is carried out, the execution of the power failure operation of the elevator that is performed by supplying power from the power storage facility 6 and the execution of the normal operation of the elevator that is performed by supplying power from the AC commercial power supply 1 are overlapped. It can be avoided. Thereby, high stability of the operation of the elevator can be ensured even during power recovery.

  In addition, this embodiment mentioned above was described in detail in order to demonstrate this invention easily, and is not necessarily limited to what is provided with all the demonstrated structures. Further, a part of the configuration of an embodiment can be replaced with the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of an embodiment.

  Further, in the present embodiment, the time from when the rescue operation device 7 at the time of a power failure is confirmed that a power failure has occurred in the elevator control device 3 during the traveling of the car in step S3 to when the operation of the elevator is stopped in step S7 Is less than 2 minutes, the case has been described where the predetermined first time T, which is a reference when the elapsed time signal is output to the control unit 11 after the timer 11A measures the time, is set to 2 minutes. However, the predetermined first time T may be appropriately changed according to the distance between floors at which the elevator stops.

  Moreover, although this embodiment is applied to the elevator provided with the rescue operation apparatus 7 at the time of a power failure, since this rescue operation apparatus 7 at the time of a power failure is provided as an option of an elevator, it is applied to all the elevators. It is not always installed. In consideration of this, the control unit 11 according to the present embodiment inputs the power failure detection signal output by the power failure detection device 8 based on the elapsed signal output by the timer 11A measuring time. Since the time until the power failure operation command signal is output to the elevator control device 3 is delayed by the predetermined first time T, the power failure is caused to the elevator by adjusting the predetermined first time T. Regardless of whether or not the hour rescue operation device 7 is installed, the same control can be used.

  In particular, in the present embodiment, it takes two minutes for the elevator to start the power failure operation after the AC commercial power source 1 is turned off. However, the rescue operation device 7 during a power failure is not installed in the elevator. However, since the predetermined first time T is set to, for example, 0 seconds or near 0 seconds, the elevator can be quickly shifted to the power failure operation, so that high convenience can be ensured.

  Further, in the present embodiment, when the control unit 11 of the monitoring unit 10 outputs a discharge switching command signal to the power conversion device 5 in order to cause the power conversion device 5 to convert the direct current extracted from the power storage facility 6 into alternating current. However, the present invention is not limited thereto, and the power failure detection device 8 may output a discharge switching command signal to the power conversion device 5 instead of the control unit 11.

DESCRIPTION OF SYMBOLS 1 AC commercial power supply 2 Distribution board 2a Primary side switch 2b-2n Secondary side switch 3 Elevator control device 4 Elevator power supply switching device 4a Power supply switching switch 5 Power conversion device 6 Power storage equipment 7 Rescue operation device at power failure 8 Power failure Detection device 10 Monitoring unit 11 Control unit 11A Timer (timer unit)
12 Input / output device 13 Storage device

Claims (2)

AC commercial power source for supplying power to the building equipment including the elevator, a power failure detection device for detecting the interruption of the power supplied by the AC commercial power source, and the power failure detection device for shutting off the power from the AC commercial power source When it is detected, when it detects power storage equipment that stores electric power to be used instead of the AC commercial power supply, an elevator control device that controls the operation of the elevator, and a cutoff of the power supplied to the elevator control device Elevator monitoring comprising: a power failure rescue operation device for performing a power failure rescue operation for moving the elevator car to the nearest floor; and a monitoring unit connected to the elevator control device for detecting an abnormality of the elevator In the device
A time measuring unit for measuring a time elapsed since the interruption of the power supply from the AC commercial power source is detected by the power failure detection device;
A switching unit that switches a source of power supplied to the elevator control device from the AC commercial power source to the power storage facility when the time measured by the time measuring unit reaches a predetermined time. Elevator monitoring device. The elevator monitoring apparatus according to claim 1,
The elevator monitoring device characterized in that the predetermined time is set to be longer than a time required for the operation of the rescue operation device at the time of a power failure to be completed after detection of interruption of power supplied to the elevator control device .

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