JPH04289776A - Data transmission method between a plurality of inverters - Google Patents

Abstract

PURPOSE:To obviate the necessity of dedicated interface by serving an I/O control terminal for normal signal as an I/O interface for serial data when a plurality of inverters are operated while being interconnected through a serial communication circuit. CONSTITUTION:Data communication is carried out between a master unit, i.e., the first inverter 1-1 out of N inverters connected through a transmission line 3, and slave units, remaining N-1 inverters. Four terminals in a control terminal i.e., block 2-1 are employed as the serial data I/O interface with an external control circuit in the communication of 1 bit data and 4 bit binary data due to modification of terminal function. For example, command input data such as operation/stop commands(HLD, FWD, REV), multi-stage speed switching commands (X1, X2, X3) are transmitted individually or simultaneously to the N inverters. Consequently, a communication data I/O interface dedicated for each inverter is not required.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data input/output method for data transmission between a plurality of inverters.

0002

2. Description of the Related Art In a conventional data transmission method of this type, a control terminal for normal signal input/output and an input/output element as an interface for serial data input/output are placed side by side in each inverter, and both are connected to each other. Each is known to be used as a unique functional element.

0003

[Problems to be Solved by the Invention] However, in the conventional data transmission method as described above, with respect to each inverter that can be operated as either a master unit or a slave unit and is manufactured in a standard manner, the above-mentioned normal signal input/output is The control terminals for the inverters and the serial data input/output interfaces are placed side by side, and the required installation space increases due to the side-by-side placement, leading to an increase in the size and price of each of the inverters. In view of this, it is an object of the present invention to provide a data transmission method between a plurality of inverters that does not require the above-mentioned co-location.

0004

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a data transmission method between a plurality of inverters, each of which has a communication function, and which can mutually operate as either a master unit or slave unit. When operating a plurality of inverters connected to each other via a serial communication line, a control terminal for normal signal input/output is also used as an interface for input/output of serial data via the communication line,
The control terminal input/output data of each of the plurality of inverters is transmitted through the control terminal of one inverter serving as a parent device, and the same number of 1-bit data as the number of parent device terminals and the same number of terminals as the number of terminals. It shall be input and output as bit data, or alternatively, instead of the one base unit,
Multiple inverters appropriately selected from among all inverters are collectively used as a parent unit, and control terminal input/output data for each of all inverters is transmitted via the control terminals of the multiple inverters serving as the parent unit. , the same number of 1-bit data as the total number of terminals in the parent device group, and data in the same number of bits as the total number of terminals are input and output.

[0005]

[Operation] In general, inverter operation methods include normal control by inputting and outputting normal signals such as contact signals or voltage and current signals, or synchronized operation of multiple units by inputting and outputting serial data via communication lines. This is determined at the time of installation of the inverter. In addition, a normal inverter itself has a manual setting section, memory, and CPU.
It has an operating condition setting section consisting of the following, etc., so that it can correspond to both of the above-mentioned operating methods. In accordance with the above, the present invention makes the normal control terminal multi-functional and doubles as the serial data input/output interface by performing a switching operation in the operating condition setting section, thereby eliminating the need to install a separate interface for the interface. be.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples of the present invention will be described below with reference to the drawings. (A) in Figure 1 is a block system diagram of N inverters connected by a transmission line (communication line) and operated in synchronization.
B) is a control terminal arrangement diagram for each of the inverters, and FIG. 2 is a configuration circuit diagram on the parent device side when two inverters are paired as a parent device. First, (b) in Figure 1 is 27
This is an example of the terminal arrangement of the control terminal block 2 which is made up of terminals and has the above-mentioned normal control display, and includes both control command signal terminals and operation display signal terminals. Next, in FIG. 1(a), 1 is an inverter, and 1-1 to
1-N indicates N inverters from the 1st to the Nth, respectively, and the terminal blocks 2-1 to 2-2, respectively.
It has N. Further, 3 is a data transmission path (communication line) that interconnects the N inverters. In the illustrated case, the first inverter 1-1 is used as a master unit, and the other N-1 inverters are used as slave units for data communication, and four terminals from the control terminal block 2-1 are used. This is an interface for serial data input/output with an external control circuit (not shown), and communicates 1-bit data and 4-bit binary data by changing the terminal function.For example, Run/stop command (
HLD, FWD, REV), multi-speed switching command (X1,
The command input data such as , frequency arrival signal (F
Outputs 1-bit data such as AR), running signal (RUN), and 4-bit binary data (trip factor) due to function changes of each of the 4 terminals (LV, OL, FAR, RUN) using the terminal 2-1. It is something that makes you Furthermore, FIG. 2 shows a system in which two of the N inverters 1-1 and 1-2 are paired as a master unit, and the other N-2 inverters are respectively slave units to deal with the increase in data required to be handled. Terminals X1 and X2 are connected from the terminal blocks 2-1 and 2-2 in the inverters 1-1 and 1-2, respectively.
, Can be done.

[0007]

According to the present invention, a plurality of inverters each having a communication function and capable of operating as either a master unit or a slave unit are connected to each other via a serial communication line and operated. In this case, a control terminal for normal signal input/output is also used as an input/output interface for serial data via the communication line, and the control terminal used as the interface is used as a master unit depending on the number of data. Alternatively, by appropriately selecting a plurality of inverters as necessary, it is possible to perform synchronized operation by transmitting data between each inverter without installing a dedicated input/output interface for communication data in each inverter,
By omitting the dedicated interface as described above, each inverter can be made smaller and less expensive.

[Brief explanation of the drawing]

[Fig. 1] Block system diagram of N inverters showing an embodiment of the present invention and control terminal arrangement diagram of each inverter.

[
Figure 2: Configuration circuit diagram of the main unit when two inverters are used as the main unit

[Explanation of symbols]

Claims (3)

[Claims] Claim 1: When operating a plurality of inverters each having a communication function and capable of operating as either a master unit or a slave unit, the normal signal input is used. A data transmission method between a plurality of inverters, characterized in that an output control terminal is also used as an input/output interface for serial data via the communication line. 2. The data transmission method between a plurality of inverters according to claim 1, wherein control terminal input/output data of each of the plurality of inverters is transmitted via a control terminal of one inverter serving as a master unit. A data transmission method between a plurality of inverters, characterized by inputting and outputting 1-bit data of the same number as the number of base terminals and data of the same number of bits as the number of terminals. 3. In the data transmission method between a plurality of inverters according to claim 2, in place of the one master unit, a plurality of inverters appropriately selected from all the inverters are collectively used as the master unit. , the control terminal input/output data of each inverter is transmitted via the control terminals of the plurality of inverters serving as the parent unit, and the same number of terminals as the total number of terminals of the parent unit group is transmitted.
A data transmission method between a plurality of inverters, characterized by inputting and outputting data in bits and data in the same number of bits as the total number of the terminals.