JPH09244712A - Load control system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To constitute a system, which can continue control over a load even in case of the occurrence of abnormality to a transmission line, at low cost. SOLUTION: A master station 1 outputs a send signal for control to 1st and 2nd transmission lines 2 and 3 under the command of a programmable controller 4. Then 1st and 2nd transmission devices 10 and 15 receives the send signal sent by the master station 1 through the 1st and 2nd transmission lines 2 and 3. Electric motor controllers 11 and 16 open and close electromagnetic contactors 13 and 18 according to the sent signal received by the transmission devices 10 and 15 to control the operations of induction motors 12 and 17. Here, the electric motor controllers 11 and 16 if detecting abnormality of the transmission lines 2 and 3 inform the opposite-side electric motor controllers 16 and 11 of the abnormality occurrence. Then the opposite-side electric motor controllers 16 and 11 controls the operations of the induction motors 12 and 17 instead of the electric motor controllers 11 and 16.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a load control system for controlling a load based on a signal received from a master station via a transmission line.

[0002]

Conventionally, for example, remote control of a plurality of electric motors has been performed, and a transmission system is provided as a means for realizing the remote control. This transmission system is composed of a master station which controls the transmission system as a whole and a transmission device which receives a command from the master station through a transmission path. In this case, the master station has a data transmission memory, and one transmission device on the transmission side is set for each transmission address set in the transmission memory, and a transmission device on the reception side is set. One or more are set including the master station.

Then, when data is transmitted from a predetermined transmission device to another transmission device, the master station transmits to the transmission device to which the address of the transmission side is set and the transmission device to which the address of the reception side is set. On the other hand, the address information including the transmission address is output to the transmission path at a predetermined timing.

Then, when each of the transmission devices connected to the transmission line receives the address information from the transmission line, it compares the address indicated by the address information with the preset address, and becomes the transmission side. The transmission device set to the address outputs the data owned by itself to the transmission line, and the transmission device to the address set to the receiving side receives the data output to the transmission line. By the above operation, data transmission is performed between the transmission devices including the master station, and the master station attempts time sharing of the transmission path.

Here, a programmable controller is connected to the master station, and the programmable controller can write and read data to and from the transmission memory of the master station. Then, when data is written in the transmission memory from the transmission device set on the transmission side, the programmable controller reads the data, processes the read data, and sends the result to a predetermined transmission memory. Write to a credit address.

As a result, data is transmitted from the master station to the transmission device set on the receiving side, so that the transmission device set on the receiving side receives the data processed by the programmable controller and sends it to the motor control device. Output. Therefore, the electric motor control device can control the electric motor according to the data from the transmission device. By the way, in the transmission system as described above, if a part of the transmission line is broken or short-circuited, data transmission between the master station and each transmission device becomes impossible, which hinders control of the electric motor. Cause

Therefore, by duplicating the transmission line from the master station and connecting the transmission devices to both transmission lines, even if a part of one transmission line is broken or short-circuited, the transmission device can operate normally. There is known a transmission system capable of continuing operation by switching to a transmission path through a transmission path. However, in such a configuration, the transmission device requires two receiving circuits and two transmitting circuits for transmitting and receiving signals from the two transmission paths, respectively, which makes the circuit complicated and expensive. There is a problem that it ends up.

The present invention has been made in view of the above circumstances, and an object thereof is to inexpensively construct a system capable of continuing control of a load even when an abnormality occurs in a transmission line. It is to provide a load control system capable of performing.

[0009]

A load control system of the present invention includes a master station that transmits a transmission signal for controlling a load in response to an external command through a first transmission line and a second transmission line. A first transmission device is provided, which is connected to the first transmission line, receives a transmission signal from the master station, and detects an abnormality of the first transmission line, and the first transmission device receives the signal. A first for controlling a first load according to a transmission signal
And a second transmission device that is connected to the second transmission line and that receives a transmission signal from the master station and that detects an abnormality in the second transmission line. A second load control device for controlling a second load according to a transmission signal received by the transmission device is provided, and the first and second load control devices are transmitted by the transmission device connected to itself. When a road abnormality is detected, the load control device on the other side is notified of the occurrence of the abnormality, and when the load control device on the other side is notified of the abnormality, the load is controlled on behalf of the load control device on the other side. (Claim 1).

In such a configuration, when the master station receives a command from the outside to control a predetermined load, it outputs a transmission signal for controlling the load to the transmission path. Then, since the transmission device receives the transmission signal from the master station, the load control device can control the load according to the transmission signal from the master station.

In this case, for example, when an abnormality occurs in the first transmission line, control of the load by the first load control device is hindered, but the first transmission device causes an abnormality in the first transmission line. Since the first load control device detects
The second load control device is notified of the occurrence of an abnormality. Accordingly, the second load control device controls the first load in place of the first load control device, so that the first load can be reliably controlled regardless of the abnormality of the first transmission path. it can.

In the above structure, the load control device is
When the abnormality of its own circuit is detected, the abnormality occurrence is transmitted to the master station through the transmission line connected to itself and the abnormality occurrence is notified to the counterpart load control device, and the abnormality is detected from the counterpart load control device. When the occurrence is notified, the abnormality occurrence may be transmitted to the master station through the transmission path connected to itself (claim 2).

In the case of such a configuration, the load control device is
When the abnormality of its own circuit is detected, the abnormality occurrence is transmitted to the master station through the transmission line connected to itself. By the way, when an abnormality occurs in the circuit of the load control device, the abnormality occurrence cannot be transmitted to the master station.
When an abnormality occurrence is notified from the load control device on the partner side, the abnormality occurrence is transmitted to the master station through the transmission path connected to itself, so that the abnormality of the load control device can be reliably transmitted to the master station. .

Further, the load control device protects the load from overload, and when detecting an abnormality of its own circuit, notifies the other load control device of the occurrence of the abnormality, and the load control device of the other side When notified of an abnormality, overload protection may be performed for the load instead of the load control device (claim 3).

In the case of such a configuration, the load control device is
When the own load becomes overloaded, the overload protection for the load prevents damage to the load. By the way, when the load control device becomes abnormal, overload protection for the load is hindered.However, when the overload control device notifies the load control device of the abnormality occurrence, the load control device Since the overload protection for the load is performed instead, the overload protection for the load can be surely performed.

Further, when the load control device is notified of the occurrence of an abnormality by the load control device on the other side, the load control device may load the load on the other side based on the transmission signal received from the master station through the transmission line connected to itself. The load may be controlled instead of the control device (claim 4).

In the case of such a configuration, when an abnormality occurs in the load control device on the partner side, the load control device on the partner side is notified of the occurrence of the abnormality, and therefore the load control device transmits the transmission connected to itself. The load is controlled on behalf of the load control device on the other side based on the transmission signal received from the master station through the road. The load can be reliably controlled according to the command from the master station.

The wiring paths of the first transmission line and the second transmission line may be different from each other (claim 5). In the case of such a configuration, even when a situation occurs in which the transmission line is disconnected due to an external factor, the wiring routes of the first and second transmission lines are different, so that both transmission lines are once Since there is no disconnection, it is possible to reliably control the load through the transmission line.

The load may be an electric motor, and the load control device may be an electric motor control device (claim 6). With such a configuration, it is possible to reliably control the electric motor.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment in which the present invention is applied to a control center control system for controlling a low voltage electric motor as a load will be described below with reference to the drawings. FIG. 1 schematically shows the configuration of a control center control system using a data transmission system. Here, the control center is, for example, one in which a plurality of control units for controlling the low-voltage electric motor are arranged in the box body.

In FIG. 1, a master station 1 for controlling a transmission system is connected to a first transmission line 2 and a second transmission line 3 and transmits / receives transmission signals through these transmission lines 2 and 3. Thereby controlling the transmission system. In this case, the master station 1 is provided integrally with the programmable controller 4, and transmits the transmission signal received from the programmable controller 4 at a predetermined timing to the first and second transmission paths 2, 2.
It is supposed to be sent to 3.

A backup master station 5 is connected to the first and second transmission lines 2 and 3 for system backup. The master station 5 has a programmable controller 6
Is connected. Then, the first and second transmission lines 5, 6
A plurality of control centers 7 are connected to the control center 7, and the control center 7 controls the operation of the induction motor.

Here, the wiring routes of the first and second transmission lines 5 and 6 between the master station 1 and the control center 7 or between the control center 7 are set to be different.
This is to prevent disconnection or short circuit of the transmission lines 2 and 3 due to external factors.

Now, the control center 7 has the first control unit 8 and the second control unit 9 built therein, and both configurations are substantially the same, so the first control unit 8 will be described. That is, the first control unit 8
Is a first transmission device 10 connected to the first transmission line 2,
A first electric motor control device 11 as a load control device integrated with the first transmission device 10 and an electromagnetic contactor 13 for driving a first induction motor 12 as a first load.
Are stored.

Here, the first transmission device 10 receives the transmission signal sent from the master station 1 via the first transmission path 2 and sends it to the first electric motor control device 11, and at the same time, When an abnormality such as disconnection or short circuit of the transmission line 2 of is detected,
A signal indicating the occurrence of abnormality is transmitted to the first electric motor control device 11.

The first electric motor control device 11 has a built-in contact 11a for an electromagnetic contactor, and the contact 11a is turned on / off according to the data received by the first transmission device 10 to turn on the first electromagnetic contactor 13. By opening and closing, the start and stop of the first induction motor 12 connected to the control center 7 are controlled. Further, the first motor control device 11 is adapted to detect a failure of its own internal device and a failure of the connected first transmission device 10, and when an abnormality is detected, the first
The fault contact 14 of is operated.

On the other hand, the second control unit 9 includes a second transmission device 15 connected to the second transmission line 3, a motor control device 16 integrated with the second transmission device 15, and a second transmission device 15. A failure of the second electromagnetic contactor 18 for controlling the start and stop of the induction motor 17, a failure of its own internal device, a failure of the connected second transmission device 15, or an abnormality of the second transmission path 3 was detected. It is configured with a second fault contact 19 that is sometimes activated.

Here, the first electric motor control device 11 has a built-in circuit 11b for reading the fault contact 19 of the second electric motor control device 16 and a contact 11c for controlling the opening / closing of the second electromagnetic contactor 18. ing. Further, the second electric motor control device 16 includes a contact 16a for opening and closing the second electromagnetic contactor 18, a circuit 16b for reading the first fault contact 14 of the first electric motor control device 11, and a first electromagnetic contact. Contactor 13
It has a built-in contact 16c for controlling opening and closing.

In this case, the first and second electric motor control devices 1
1, 16 have the following functions. When it is detected that the fault contacts 14 and 19 are turned on, it is determined that the electric motor control devices 11 and 16 on the other side are abnormal, and the induction motors 12 and 17 are replaced by the electric motor control devices 11 and 16 on the other side. The operation is controlled and the abnormality occurrence is transmitted to the master station 1 through the transmission lines 2 and 3 connected to itself.

When it is determined that the induction motors 12 and 17 are in an overload state, the energization of the induction motors 12 and 17 is stopped and the overload protection is further performed.
When an abnormality in the electric motor control device 11, 16 on the partner side is detected, overload protection is performed on the induction motors 12, 17 in place of the electric motor control device 11, 16 on the partner side.

When a transmission signal for the induction motors 12, 17 on the other side is received from the master station 1 through the transmission lines 2, 3 connected to itself, the electric motor control unit 11, on the other side,
Instead of 16, the induction motors 12, 17 are controlled.

Next, to explain the operation of the above configuration,
The specific data transmission method between the master station 1 and each of the transmission devices 10 and 15 is the same as that described in the conventional example, and thus detailed description thereof will be omitted. When controlling the operation of, for example, the first induction motor 12 connected to the control center 7, the programmable controller 4 indicates that the master station 1 is the transmission side and the first transmission device 10 is the reception side and controls the control. The address information indicating the contents is stored at a predetermined address in the transmission memory of the master station 1.

Then, the master station 1 outputs the address information stored in the predetermined address of the transmission memory to the first and second transmission lines 2 and 3 at a predetermined timing. And the first
The first transmission device 10 connected to the transmission line 2 receives the transmission signal from the master station 1 through the first transmission line 2, sets itself to the receiving side according to the transmission signal, and The control content included in the information is the first electric motor control device 1
Notify 1.

As a result, the first motor control device 11
Is the contact 1 depending on the control content from the first transmission device 10.
Since the first electromagnetic contactor 13 is opened / closed by turning on / off 1a, the first electromagnetic contactor 13 connected to the control center 7
The operation of the induction motor 12 can be controlled.

Similarly, when controlling the operation of the second induction motor 17, a transmission signal indicating that the second transmission device 15 is the receiving side and indicating the control content is transmitted from the master station 1 to the first and first transmission signals. By transmitting to the second transmission device 15 through the two transmission lines 2 and 3, the operation of the second induction motor 17 can be controlled.

Now, disconnection in the first and second transmission lines 2 and 3,
Alternatively, when an abnormality such as a short circuit occurs, it becomes impossible to transmit a transmission signal to each of the transmission devices 10 and 15 connected to these transmission paths 2 and 3, and each motor control device 11 and
The control of the induction motors 12 and 17 by 16 cannot be executed.

Therefore, in this embodiment, the control for each induction motor 12, 17 is surely executed as follows. That is, when an abnormality occurs in the first transmission line 2, the first transmission device 10 connected to the first transmission line 2 detects the abnormality in the first transmission line 2 and detects the first Notify the motor control device 11. Then, the first electric motor control device 11 causes the first failure contact 1 provided corresponding to itself.
Turn on 4.

Then, the circuit 16b incorporated in the second electric motor control device 16 detects that the first fault contact 14 is turned on, so that the second electric motor control device 16 follows the program incorporated in advance. , The transmission signal transmitted from the programmable controller 4 to the first transmission device 10 via the master station 1, the second transmission path 3, and the second transmission device 15, and according to the transmission signal, By turning on / off the built-in contact 16c, the operation of the first induction motor 12 is controlled in place of the first electric motor control device 11.

Similarly, when an abnormality occurs in the second transmission line 3, the second fault contact 19 is turned on, so that the first motor control device 11 replaces the second motor control device 16. The operation of the second induction motor 17 is controlled.

In this case, the fault contacts 14 and 19 are the first and second
Since the operation is performed even when the second electric motor control device 11, 16 or the first and second transmission devices 10, 15 fail, the second and first electric motor control devices 16, 11 have the first failure contact point. When it is detected that 14 and 19 are turned on,
The first and second electric motor control devices 11 and 16 are replaced with first and second electric motor control devices.
The operations of the first and second induction motors 12 and 17 can be reliably controlled by opening and closing the electromagnetic contactors 13 and 18.

Further, the first and second electric motor control devices 11,
16 has a function of detecting an abnormality of its own circuit, and when an abnormality is detected, the master station 1 transmits a transmission signal indicating the abnormality through the first and second transmission paths 2 and 3 connected to itself. To the second and first fault contacts 19, 14
When is turned on, the occurrence of abnormalities
It is transmitted to the master station 1 through the second transmission lines 2 and 3.

On the other hand, the master station 1 has the first and second transmission paths 2, 2.
When the transmission signal indicating the abnormality of the first and second electric motor control devices 11 and 16 is received through 3, the user is notified that the abnormality has occurred in the first and second electric motor control devices 11 and 16. . Thereby, the first and second electric motor control devices 1
It is possible to quickly deal with the abnormalities 1 and 16.

The first and second electric motor control devices 11,
When the first and second induction motors 12 and 17 are in an overload state, 16 executes overload protection by stopping energization of these induction motors 12 and 17.
Here, the first and second electric motor control devices 11 and 16 replace the second and first electric motor control devices 16 and 11 when the second and first fault contacts 19 and 14 are turned on. Two
Overload protection for the first induction motors 17 and 12 is performed.

When the master station 1 becomes abnormal, a control transmission signal is transmitted from the backup master station 5 to each of the transmission devices 10 and 15 through the first and second transmission paths. The abnormality of the master station 1 can also be dealt with.

According to the above configuration, the first and second transmission lines 2 and 3 connected to the master station 1 are respectively connected to the two first and second transmission devices 10 and 15 provided in the control center 7. The transmission path connected to the other side electric motor control device 11 and 16 is controlled by connecting and controlling the predetermined induction motors 12 and 17 by outputting a control transmission signal from the master station 1 to the transmission paths 2 and 3. When 2 or 3 becomes abnormal, or when the other party's electric motor control device 11, 16 becomes abnormal, the other side's induction motors 12, 17 are controlled. It is possible to construct a highly reliable transmission system at a low price, as compared with a configuration in which two transmission lines are connected and duplexed.

Further, the electric motor control devices 11 and 16 on the other side
Even if the master cannot notify his / her own abnormality to the master station 1, since the abnormality of the other party is notified to the master station 1, the abnormality of the first and second electric motor control devices 11 and 16 is detected. It is possible to reliably transmit to the master station and deal with abnormally promptly.

Further, the motor control devices 11, 16 on the other side
Even if it is not possible to perform overload protection on the induction motors 12, 17 on the other side due to the occurrence of the abnormal condition, the overload protection for the induction motors 12, 17 is performed on behalf of the electric motor control units 11, 16 on the other side. Since it is executed, the overload protection for the first and second induction motors 12 and 17 can be surely executed regardless of the abnormality of the first and second electric motor control devices 11 and 16.

Furthermore, since the wiring paths of the first and second transmission lines 2 and 3 are made different, it is possible that an unexpected force is applied to one of the transmission lines 2 and 3 due to an external factor to break the wire. Even if a situation occurs, the other transmission lines 2 and 3 will not be disconnected at the same time. Therefore, the normal transmission line 2,
3, the control of the induction motors 12 and 17 can be surely executed.

[0049]

As is apparent from the above description, the load control system of the present invention has the following effects. According to the first aspect, the first and second load control devices notify the load control device on the other side of the occurrence of the abnormality when the transmission device connected to itself detects the abnormality of the transmission path. In addition, since the load is controlled instead of the load control device on the partner side when the load control device on the partner side notifies the load, control of the load is performed even if a fault occurs on the transmission line. You can continue. In this case, since one transmission device corresponds to the load control device, the system can be constructed at a low cost as compared with the configuration in which the transmission line is duplicated.

According to the second aspect of the present invention, when the load control device detects the abnormality of its own circuit, it transmits the abnormality occurrence to the master station through the transmission line connected to the load control device and the abnormality occurrence side on the other side. To the master station through the transmission path connected to itself, when the load control device on the other side is notified of the abnormality occurrence by the load control device on the other side, the abnormality of the load control device is transmitted to the master station. Can be reliably sent to.

According to the third aspect of the present invention, the load control device performs overload protection for the load, and when it detects an abnormality in its own circuit, notifies the other load control device of the occurrence of the abnormality, and When the load control device on the other side notifies the load control device of the abnormality, the overload protection for the load is performed in place of the load control device, so that the overload control for the load can be reliably performed.

According to the fourth aspect of the present invention, when the load control device on the other side notifies the load control device of the occurrence of an abnormality, the load control device transmits the transmission signal received from the master station through the transmission path connected to itself. Since the load is controlled on the basis of the load control device on the other side, the load can be reliably controlled.

According to the fifth aspect of the invention, since the wiring paths of the first transmission path and the second transmission path are different, it is possible to reliably control the load through the transmission path.

According to the sixth aspect, since the load is the electric motor and the load control device is the electric motor control device,
It is possible to reliably control the electric motor.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing an overall configuration according to an embodiment of the present invention.

[Explanation of symbols]

1 is a master station, 2 is a first transmission line, 3 is a second transmission line, 7 is a control center, 8 is a first control unit, 9 is a second control unit, 10 is a first transmission device, 11 is the first
Motor controller (first load controller), 12 is the first
Induction motor (first load), 14 is a first fault contact,
Reference numeral 15 is a second transmission device, 16 is a second electric motor control device (second load control device), 17 is a second induction motor (second load), and 19 is a second fault contact.

Claims (6)

[Claims] 1. A master station for transmitting a transmission signal for controlling a load according to a command from the outside through a first transmission path and a second transmission path; and a master station connected to the first transmission path. A first receiving a transmission signal from the station and detecting an abnormality of the first transmission line;
Transmission device, a first load control device for controlling a first load according to a transmission signal received by the first transmission device, and a transmission signal from the master station connected to the second transmission path. And a second detecting the abnormality of the second transmission line.
And a second load control device that controls a second load according to a transmission signal received by the second transmission device, wherein the first and second load control devices are self-serving. When the connected transmission device detects an abnormality in the transmission line, the load control device on the other side is notified of the abnormality occurrence, and when the load control device on the other side is notified of the abnormality occurrence, the load control on the partner side is performed. A load control system characterized by controlling a load instead of a device. 2. When the load control device detects an abnormality of its own circuit, the load control device transmits an abnormality occurrence to the master station through a transmission line connected to itself and notifies the load control device of the other party of the abnormality occurrence. The load control system according to claim 1, wherein when the load control device on the other side notifies the abnormality occurrence, the abnormality occurrence is transmitted to the master station through a transmission line connected to itself. 3. The load control device performs overload protection against a load, notifies the other side load control device of the occurrence of an abnormality when detecting an abnormality of its own circuit, and from the other side load control device. The load control system according to claim 1 or 2, wherein, when notified of the occurrence of an abnormality, overload protection for a load is performed instead of the load control device. 4. The load control device, when notified by the load control device of the other party that an abnormality has occurred, based on a transmission signal received from the master station through a transmission line connected to the load control device of the other party, the load control apparatus of the other party The load control system according to any one of claims 1 to 3, wherein the load is controlled instead of the control device. 5. The load control system according to claim 1, wherein the wiring paths of the first transmission line and the second transmission line are different from each other. 6. The load control system according to claim 1, wherein the load is an electric motor, and the load control device is an electric motor control device.