JP2018036800A - Apparatus, system, and method for control - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress increase of a time until an apparatus is activated while reducing the possibility of occurrence of failures of activating the apparatus.SOLUTION: In a system 9, the apparatus includes: a power source for a load part which receives power supply from a first power source and supplies power to a load part; a switch which is provided between the first power source and the load part power source; a control unit which is activated when the first power source starts supplying power; and a storage unit which stores a parameter for calculating a delay time from activation of the control unit to start of power supply to the power source for the load part. The control unit calculates the delay time on the basis of the parameter so that the delay time is shorter than a predetermined maximum delay time and sets the switch in an on-state when the delay time has passed.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a device, a system, and a control method.

  Conventionally, a delay time corresponding to an identification number is set for each slave station connected to the slave station power supply device, and a switch in each slave station when the delay time has elapsed since the slave station power supply device supplied power There is known a system for turning on the signal (for example, Patent Document 1). Thereby, each slave station is sequentially activated.

JP 2006-345608 A

  In the above-mentioned Patent Document 1, since a slave station is added and the pattern of delay time increases, the time required for starting all the slave stations becomes long. If the maximum delay time is limited in order to avoid this, there is a possibility that the delay times coincide with each other in a plurality of slave stations.

  An object of the present invention made in view of such circumstances is to provide a device, a system, and a control method capable of reducing an increase in time until the device is activated while reducing a possibility that the activation of the device is failed. There is to do.

  An apparatus according to an embodiment of the present invention is provided between a power supply for a load unit that receives power supply from a first power supply and supplies power to the load unit, and between the first power supply and the power supply for the load unit. A switch and a control unit that is activated when power supply from the first power source is started. The device according to an embodiment of the present invention further includes a storage unit that stores a parameter for calculating a delay time from the start of the control unit to the start of power supply to the load unit power supply. The control unit calculates the delay time so as to be less than a predetermined maximum delay time based on the parameter, and sets the switch to an ON state when the delay time elapses.

  In addition, a control method according to an embodiment of the present invention includes a power supply for a load unit that receives power supply from a first power supply and supplies power to the load unit, and a power supply between the first power supply and the power supply for the load unit. A switch provided, a control unit that starts when power supply from the first power supply is started, and a delay time from the start of the control unit to the start of power supply to the power supply for the load unit And a storage unit for storing the parameters. The control method according to an embodiment of the present invention includes a step of calculating the delay time so as to be less than a predetermined maximum delay time based on the parameter, and setting the switch to an ON state when the delay time has elapsed. Steps.

  Moreover, the system which concerns on one Embodiment of this invention has a some apparatus and 1st power supply. Each of the plurality of devices includes a power supply for a load unit that receives power supply from the first power supply and supplies power to the load unit, and a switch provided between the first power supply and the power supply for the load unit , Storing a control unit that starts when power supply from the first power supply is started, and a parameter for calculating a delay time from the start of the control unit to the start of power supply to the power supply for the load unit And a storage unit. The control unit calculates the delay time so as to be less than a predetermined maximum delay time based on the parameter, and sets the switch to an ON state when the delay time elapses.

  According to the device, the system, and the control method according to the embodiment of the present invention, it is possible to reduce an increase in time until the device is activated while reducing the possibility that the device is unsuccessfully activated.

It is a functional block diagram of a system concerning an embodiment of the present invention. It is a figure which shows the relationship between time and the electric current which flows into a system. It is an example of the table which the memory | storage part in the system of FIG. 1 memorize | stores. It is another example of the table which the memory | storage part in the system of FIG. 1 memorize | stores. It is an example of each value in calculation of the delay time of the apparatus in the system of FIG. It is an example of each value in calculation of the delay time of the other apparatus in the system of FIG. It is an example of each value in calculation of the delay time of the other apparatus in the system of FIG. It is a flowchart which shows operation | movement of the control part in the system of FIG.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a functional block diagram of a system 9 according to an embodiment of the present invention. The system 9 is a power supply control system including a plurality of devices and the first power supply 2. Although the number of a plurality of devices is not limited, in the present embodiment, for convenience of explanation, the plurality of devices will be described as a device 1a, a device 1b, and a device 1c. The device 1a, the device 1b, and the device 1c may be the same model or different models. The devices 1a, 1b, and 1c are connected to the first power supply 2 in parallel. An overcurrent protection device 3 is provided on a common line between the first power supply 2 and the devices 1a, 1b, and 1c. In FIG. 1, the power line is indicated by a solid line, and the control line or the information transmission line is indicated by a broken line.

  The device 1a is an arbitrary load device that is driven by receiving power supply from the first power supply 2, and is an electric product including a motor such as an air conditioner or a refrigerator. The device 1a includes a switch 11a, a load unit power supply 12a, a load unit 13a, a control unit 14a, and a storage unit 15a. The device 1a may have a control power source on the overcurrent protection device 3 side of the control unit 14a, and may be configured to start the control unit 14a when the control unit 14a receives power supply from the control power source. . However, in this embodiment, the description of the control power supply is omitted for the sake of simplicity.

  The switch 11a is, for example, a relay. The switch 11a is provided between the overcurrent protection device 3 and the load unit power supply 12a, and is controlled by the control unit 14a by switching between an on state and an off state.

  The load unit power supply 12a is, for example, a power supply for the device 1a, but is not limited thereto. The load part power supply 12a is provided between the switch 11a and the load part 13a. When the switch 11a is set to the on state, the load unit power supply 12a receives power from the first power supply 2 and supplies power to the load unit 13a. When power supply to the load unit power supply 12a is started, a transient inrush current is generated in the device 1a regardless of whether the power supply of the load unit 13a is turned on or off. When the switch 11a is set to the OFF state, the power supply to the load unit power supply 12a is stopped.

  The load unit 13a consumes power supplied from the load unit power supply 12a. Although only one load part 13a is shown in FIG. 1, the number of load parts 13a is not limited.

  The control unit 14a is activated when power supply from the first power supply 2 is started, and controls and manages the entire device 1a including each functional unit of the device 1a. The control unit 14a is configured by a processor such as a CPU (Central Processing Unit) that executes a program that defines a control procedure. The program is stored in, for example, the storage unit 15a or an external storage medium.

  The control unit 14a calculates the delay time of the device 1a based on the parameters stored in the storage unit 15a. When the calculated delay time elapses from when the control unit 14a is activated, the control unit 14a sets the switch 11a to an on state. As a result, power is supplied from the first power source 2 to the load unit power source 12a, and the load unit 13a is energized. Details will be described later.

  The storage unit 15a can be configured by a semiconductor memory, a magnetic memory, or the like, and stores the above-described parameters, various information, various data, a program for operating the device 1a, and the like. The storage unit 15a also functions as a work memory. For example, the storage unit 15a stores, as parameters, the identification number of the device 1a, the number of activations of the device 1a (hereinafter also referred to as the number of activations of the control unit 14a), and the like. Details will be described later.

  As illustrated in FIG. 1, the device 1b includes a switch 11b, a load unit power supply 12b, a load unit 13b, a control unit 14b, and a storage unit 15b. The device 1c includes a switch 11c, a load unit power supply 12c, a load unit 13c, a control unit 14c, and a storage unit 15c. Since the functional block diagrams of the device 1b and the device 1c are the same as the functional block diagram of the device 1a, description thereof will be omitted.

  The first power supply 2 is, for example, a power generation device at the time of a power failure in a commercial system, a commercial system, or the like, and supplies AC power to the devices 1a, 1b, and 1c. When the first power supply 2 is, for example, a power generation device at the time of a power failure in a commercial system, the power generation device is connected to a so-called multi-DC link system in which a power conditioner converts a plurality of direct currents into alternating currents to perform power control. Is done. When the power generation device is driven by a user operation and the power conditioner is set to an independent state, the first power supply 2 starts supplying power, and when the power generation device is stopped by a user operation, the first power supply 2 supplies power. To stop. On the other hand, when the first power source 2 is, for example, a commercial system, the first power source 2 starts supplying power when the breaker is set to an on state by a user operation, and when the breaker is set to an off state by a user operation Alternatively, the first power supply 2 stops supplying power when a power failure occurs.

  In this embodiment, the overcurrent protection device 3 is connected to the first power supply 2 side of the device 1a, the device 1a, and the device 1c as shown in FIG. The overcurrent protection device 3 can cut off the power line when it is determined that an overcurrent has flowed. The presence or absence of the overcurrent protection device 3 is optional, but the overcurrent protection device 3 may be provided when the first power source 2 is an emergency power generation device in which the maximum current is limited.

  For example, when the first power supply 2 starts supplying power to the devices 1a, 1b, and 1c connected to an outlet, the control unit 14a, the control unit 14b, and the control unit 14c are energized and activated. . At this time, if the switch 11a is set to the ON state, power is also supplied to the load unit power supply 12a, and an inrush current flows through the device 1a. Similarly, when the switch 11b and the switch 11c are set to the on state, power is also supplied to the load unit power source 12b and the load unit power source 12c, respectively, and an inrush current flows also to the device 1b and the device 1c. When power is simultaneously supplied to the load unit power supply 12a, the load unit power supply 12b, and the load unit power supply 12c, the inrush currents are added together, and a large current flows through the system 9. The total value of the inrush current increases as the number of devices connected in parallel increases. The time at which power is supplied to the load section power supply 12a, the load section power supply 12b, and the load section power supply 12c is time t1, and the current at that time is shown by a curve C1 in FIG. If this inrush current exceeds the current at which the overcurrent protection device 3 is activated, the overcurrent protection device 3 may be activated, and power supply to the devices 1a, 1b, and 1c may be stopped.

  Therefore, in the system 9 of the present embodiment, for example, the timing at which power is supplied to the load unit power source 12a, the load unit power source 12b, and the load unit power source 12c is, for example, as shown in FIG. And it shifts as time t3. In this case, the current flowing through the system 9 is shown by a curve C2 in FIG. Thereby, a possibility that the overcurrent which starts the overcurrent protection apparatus 3 may flow into the system 9 can be reduced.

  Hereinafter, the control method in the present embodiment will be described in detail. Since the processing executed by the device 1a, the device 1b, and the device 1c in the present embodiment is the same, the following description focuses on the operation performed by the device 1a for the sake of simplicity of explanation.

  When power is supplied from the first power supply 2 to the device 1a by a user operation, the control unit 14a is activated. The controller 14a starts counting elapsed time using, for example, a timer. The control unit 14a acquires the identification number of the device 1a and the number of activations of the device 1a as parameters from the storage unit 15a, and calculates the delay time of the device 1a based on the acquired value.

  The identification number of the device 1a may be a number given at the time of manufacturing the device 1a, or may be a manufacturing number or a serial number of the device 1a. The identification number is stored in the storage unit 15a as shown in FIG. 3A. The number of activations is also stored in the storage unit 15a as shown in FIG. 3A, and the initial value is zero.

The delay time is the time from when power is supplied to the control unit 14a until the switch 11a is set to the on state. The delay time calculation formula is, for example, as follows.
(Delay time) = (Delay unit time) x (Remainder when the hash operation value is divided by the maximum delay coefficient)

  The delay unit time is set as the minimum value of the difference in activation time between devices, and is stored in the storage unit 15a as shown in FIG. 3A. For example, when at least 100 [ms] is required as the activation interval for each device in order to prevent an inrush current from occurring in a plurality of devices at the same time, the delay unit time is set as 100 [ms]. As an alternative example, the delay unit time may be, for example, 20 [ms] or 40 [ms].

  The hash operation value is an operation result of an arbitrary function that outputs different summary values (output values) for different arguments using the identification number of the device 1a and the number of activations of the device 1a as arguments. The argument of the function in the present embodiment is, for example, a bitwise exclusive OR of a binary identification number and a binary activation count. A table showing exclusive OR is shown in FIG. 3B. In the present embodiment, as an example, the summary value is a natural number. For a function that outputs different summary values (output values) for different arguments, a hash function such as an MD (Message Digest) 5 algorithm can be used.

  For example, when all the devices are installed at the same time, the number of activations of the device 1a may be the same as the number of activations of the device 1b or the device 1c. Therefore, in addition to the number of activations of the device 1a, an identification number that differs for each device may be used as an argument.

  The maximum delay coefficient is a value obtained by dividing an arbitrary maximum delay time (for example, 2000 [ms]) allowed as the time until the devices 1a, 1b, and 1c are activated by the delay unit time. The maximum delay coefficient can be arbitrarily set by the user. In the above formula for calculating the delay time, the delay time is obtained by multiplying the delay unit time by the remainder when the hash operation value is divided by the maximum delay coefficient. Since the remainder is below the maximum delay factor, the resulting delay time is below the maximum allowable delay time. The maximum delay time and the maximum delay coefficient are stored in the storage unit 15a as illustrated in FIG. 3A.

  In the example of FIG. 3A, the delay unit time, the maximum delay coefficient, and the maximum delay time are 100 [ms], 20 and 2000 [ms], respectively. For this reason, the difference in delay time between devices is at least 100 [ms], and the time required for starting all devices is less than 2000 [ms].

  In the present embodiment, as an example, the initial value of the delay time of the devices 1a, 1b, and 1c is 100 [ms]. The control unit 14a counts up (that is, increases) the number of activations of the device 1a by one. The control unit 14a stores the number of activations after counting up in a table in the storage unit 15a.

  The control unit 14a sets the switch 11a to the on state when 100 [ms], which is a delay time, has elapsed since the start of the control unit 14a. As a result, the load unit power supply 12 a receives power supply from the first power supply 2. Similarly, the control unit 14b of the device 1b also sets the switch 11b to the on state when the delay time of 100 [ms] has elapsed. As a result, the load unit power supply 12 b receives power supply from the first power supply 2. Similarly, the load unit power supply 12 c also receives power supply from the first power supply 2.

  When the devices are activated for the first time, the delay times of the devices coincide with each other. Therefore, an overcurrent occurs in the system 9 due to the inrush current, and the activation of each device fails. However, in the system 9 according to the present embodiment, even if the delay times of the devices coincide, it may be possible to retry activation by a user operation. The user operation is, for example, an operation for driving the power generation device or an operation for setting the breaker to an on state.

  When the activation is retried by the user operation, the control unit 14a calculates the delay time of the device 1a using the delay time calculation formula. Each value calculated at this time is shown in FIG. 3C. In this embodiment, as an example, the identification number of the device 1a is E. This is expressed as 1110 in binary. The control unit 14a calculates an exclusive OR of the binary identification number and the binary activation count. The exclusive OR at this time is 1111 in binary. The control unit 14a converts the binary exclusive OR into a decimal summary value. The summary value at this time is 15. The control unit 14a calculates a delay time of 1500 [ms] for the device 1a by multiplying the delay unit time of 100 [ms] by the summary value of 15.

  Similarly, the control unit 14b of the device 1b calculates the delay time of the device 1b, and the control unit 14c of the device 1c calculates the delay time of the device 1c. The delay time calculation formula is common to each device. Each value calculated at this time is shown in FIG. 3D and FIG. 3E, and since the calculation method is the same as the calculation method executed by the control unit 14 a, description thereof is omitted. As a result of the calculation, the delay time of the device 1b is 1200 [ms], and the delay time of the device 1c is 1300 [ms]. Therefore, the delay time varies from device to device. According to the present embodiment, even if the devices communicate with each other via the network and do not adjust the delay time, the delay time is likely to be calculated differently for each device, and the delay time of any device is also increased. Below the maximum delay time.

  The control unit 14a increments the number of activations of the device 1a by one.

  When the delay time calculated for the device 1a has elapsed, the control unit 14a sets the switch 11a to the on state. As a result, the load unit power supply 12 a receives power supply from the first power supply 2. Similarly, the control unit 14b of the device 1b also sets the switch 11b to the on state when the delay time calculated for the device 1b has elapsed. As a result, the load unit power supply 12 b receives power supply from the first power supply 2. Similarly, the load unit power supply 12 c also receives power supply from the first power supply 2. Since the delay times of the devices 1a, 1b, and 1c are different from each other, no overcurrent flows through the system 9, and power supply to the devices 1a, 1b, and 1c continues.

  The control unit 14a starts counting elapsed time when power supply to the load unit power supply 12a is started. The control unit 14a determines whether or not a first predetermined time has elapsed since the start of power supply to the load unit power supply 12a.

  The first predetermined time is, for example, until the overcurrent protection device 3 operates due to the inrush current that occurs when power is simultaneously supplied to the load unit power supply 12a, the load unit power supply 12b, and the load unit power supply 12c. It is set longer than the time. When the first predetermined time elapses without the overcurrent protection device 3 operating, there is no possibility of overcurrent. For this reason, when the control unit 14a is activated again, if the delay time calculated most recently is used again to set the switch 11a to the on state, there is no possibility of overcurrent in the system 9.

  Therefore, if the control unit 14a determines that the device 1a is continuously activated until the first predetermined time has elapsed, the control unit 14a counts down (that is, decreases) the number of activations stored in the storage unit 15a by one. As a result, the control unit 14a uses the number of activations before being counted up again in the next calculation of the delay time, so the delay time calculated most recently can be used again.

  The control unit 14a keeps the switch 11a in the on state until the power supply from the first power supply 2 is stopped or a user operation for turning off the switch 11a is accepted.

  If the power supply from the first power supply 2 to the control unit 14a is stopped before the first predetermined time elapses due to a power failure or the like, the control unit 14a stops. In this case, since the control unit 14a does not determine whether or not the first predetermined time has elapsed, the control unit 14a maintains the number of activations without counting down.

  FIG. 4 is a flowchart illustrating an operation when the control unit 14a of the device 1a shifts from a state in which no power is supplied from the first power supply 2 to a state in which it is received. The control unit 14b of the device 1b and the control unit 14c of the device 1c also execute this flowchart in the same manner, but the description thereof is omitted for simplification.

  In step S <b> 1, the control unit 14 a is activated by receiving power supply from the first power supply 2. In step S2, the control unit 14a starts counting elapsed time after activation. In step S3, the control unit 14a acquires a parameter such as the identification number of the device 1a from the storage unit 15a, and calculates the delay time of the device 1a based on the parameter. In the present embodiment, when the calculation of the delay time in step S3 is the calculation at the first activation of the device 1a, the delay time is set to 100 [ms] as an example.

  In step S4, the control unit 14a increments the activation count of the device 1a stored in the storage unit 15a by one. In step S5, the control unit 14a determines whether or not the delay time calculated in step S3 has elapsed since the activation.

  When No in step S5, the control unit 14a executes step S5 again. On the other hand, if Yes in step S5, in step S6, the control unit 14a sets the switch 11a to the on state and starts supplying power to the load unit power supply 12a.

  When power supply is started, the control unit 14a starts counting elapsed time in step S7. In step S8, the control unit 14a determines whether or not the control unit 14a is continuously activated until the first predetermined time has elapsed from the start of power supply to the load unit power supply 12a. Since the example of the first predetermined time is as described above, description thereof is omitted here.

  When No in step S8, the control unit 14a executes step S8 again. On the other hand, if Yes in step S8, in step S9, the control unit 14a counts down the number of activations stored in the storage unit 15a by one.

  According to the present embodiment, the control unit 14a calculates the delay time of the device 1a based on the parameters stored in the storage unit 15a so as to be less than the predetermined maximum delay time, and when the delay time elapses, the switch 11a. Set to on. That is, since the delay time is calculated using information stored in the storage unit 15a of the device 1a, the possibility that the delay time is calculated differently from other devices increases. Therefore, it is possible to reduce the failure of the activation of the device 1a due to the overcurrent flowing through the system 9. Moreover, it can reduce that the time until the apparatus 1a starts is increased. Furthermore, since the necessity to assume that the inrush current is added by the number of devices is reduced, when the first power supply 2 is a power generation device, the capacity of the power generation device can be reduced.

  According to the present embodiment, the parameter includes at least one of the identification number of the device 1a and the number of activations of the device 1a. The identification number of the device 1a is different from the identification numbers of the devices 1b and 1c. Further, the number of activations of the device 1a may be different from the number of activations of the device 1b and the device 1c unless the installation time is the same as that of the devices 1b and 1c. Therefore, it is possible to increase the possibility that a different delay time can be calculated for each device.

  Further, according to the present embodiment, when the parameter includes the number of activations, the control unit 14a counts up the number of activations. The controller 14a counts up the number of activations before the delay time elapses. Since the control unit 14a sets the switch 11a to the on state after the delay time has elapsed, the control unit 14a may stop and count up the number of activations if the delay time coincides between a plurality of devices by chance. Can not. Therefore, when the control unit 14a counts up the number of activations before the delay time elapses, the activation number is accurately counted.

  Further, according to the present embodiment, when the control unit 14a determines that the device 1a is continuously activated until the first predetermined time elapses from the start of supply of power to the load unit power supply 12a, the activation is started. Count down the number of times. When the device 1a is continuously activated, there is a high possibility that no overcurrent has occurred. Therefore, by counting down the number of activations, the control unit 14a again uses the number of activations before counting up in the calculation of the next delay time. Therefore, since the most recently calculated delay time is used again, it is possible to reduce the possibility of overcurrent in the system 9.

  Further, according to the present embodiment, the first predetermined time is the time until the overcurrent protection device 3 arranged on the first power supply 2 side operates due to the inrush current generated when a plurality of devices are activated simultaneously. Set longer than time. For this reason, the possibility that an overcurrent may occur in the system 9 can be avoided.

  Although one embodiment of the present invention has been described based on the drawings and examples, it should be noted that those skilled in the art can easily make various changes or modifications based on the present disclosure. Therefore, it should be noted that these variations or modifications are included in the scope of the present invention. For example, functions included in each member, each part, each step, and the like can be rearranged so as not to be logically contradictory. Also, when implementing the present invention as a method invention, it is possible to combine or divide a plurality of parts or steps into one.

  For example, the control unit 14a may count up the number of activations of the device 1a before calculating the delay time of the device 1a or after the delay time has elapsed.

  Moreover, in the said embodiment, although the parameter used for calculation of delay time is the identification number of the apparatus 1a, and the frequency | count of starting of the apparatus 1a, it may be at least one of the said identification number and the said frequency | count of activation. When only the number of activations is used, the control unit 14a communicates with the device 1b and the device 1c to determine whether the number of activations of the device 1a is the same as the number of activations of the device 1b or the device 1c. For example, only the number of activations may be used as a parameter.

  In the above embodiment, the initial value of the delay time of each device is 100 [ms]. However, the control unit 14a may calculate the delay time for the device 1a from the initial activation without using the delay time as an initial value, using the delay time calculation formula. The same applies to the control unit 14b and the control unit 14c.

  Moreover, the control part 14a, the control part 14b, or the control part 14c which concerns on one Embodiment of this invention can be comprised with a computer. At this time, a program in which processing contents for realizing each function are described is stored in an internal or external storage unit of the computer, and the program is read and executed by a central processing unit (CPU) of the computer. The unit 14a, the control unit 14b, or the control unit 14c can be realized. Such a program can be distributed by selling, transferring, or lending a portable recording medium such as a DVD (Digital Versatile Disc) or a CD-ROM (Compact Disc-Read Only Memory). Further, such a program can be distributed by storing it in a storage unit of a server on a network, for example, and transferring the program from the server to another computer via the network. In addition, a computer that executes such a program can temporarily store, for example, a program recorded on a portable recording medium or a program transferred from a server in its own storage unit. As another embodiment of the program, a computer may read the program directly from a portable recording medium and execute processing according to the program. Further, each time a program is transferred from the server to the computer, processing according to the received program may be executed sequentially.

1a, 1b, 1c Device 11a, 11b, 11c Switch 12a, 12b, 12c Load unit power supply 13a, 13b, 13c Load unit 14a, 14b, 14c Control unit 15a, 15b, 15c Storage unit 2 First power supply 3 Overcurrent protection Device 9 system

Claims (8)

A power supply for a load unit that receives power supply from the first power supply and supplies power to the load unit;
A switch provided between the first power supply and the load power supply;
A control unit that is activated when power supply from the first power source is started;
A storage unit for storing a parameter for calculating a delay time from the start of the control unit to the start of power supply to the load unit power supply;
Have
The control unit is a device that calculates the delay time to be less than a predetermined maximum delay time based on the parameter, and sets the switch to an ON state when the delay time has elapsed. The device of claim 1,
The parameter includes at least one of an identification number of the device and the number of activations of the device. The device according to claim 2,
When the parameter includes the number of activations,
The control unit is a device that counts up the number of activations. The device according to claim 3,
The said control part is an apparatus which counts up the said frequency | count of activation before progress of the said delay time. The device according to claim 3 or 4,
The control unit counts down the number of times of activation when it is determined that the device is continuously activated until a first predetermined time elapses from the start of power supply to the load unit power supply. The device according to claim 5, wherein
The first predetermined time is set longer than a time until an overcurrent protection device arranged on the first power supply side is activated due to an inrush current generated when a plurality of devices are activated simultaneously. . A power supply for a load unit that receives power supply from the first power supply and supplies power to the load unit;
A switch provided between the first power supply and the load power supply;
A control unit that is activated when power supply from the first power source is started;
A storage unit for storing a parameter for calculating a delay time from the start of the control unit to the start of power supply to the load unit power supply;
A control method in a device having
Calculating the delay time to be less than a predetermined maximum delay time based on the parameter;
Setting the switch to an on state when the delay time has elapsed;
A control method. A plurality of devices and a first power source;
Each of the plurality of devices is
A power supply for a load unit that receives power supply from the first power supply and supplies power to the load unit;
A switch provided between the first power supply and the load power supply;
A control unit that is activated when power supply from the first power source is started;
A storage unit for storing a parameter for calculating a delay time from the start of the control unit to the start of power supply to the load unit power supply;
Have
The control unit calculates the delay time to be less than a predetermined maximum delay time based on the parameter, and sets the switch to an on state when the delay time has elapsed.
system.

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