JP2964836B2 - Temperature controller and temperature instrumentation system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a temperature controller used in combination with a general-purpose sequencer, and more particularly to an improvement in data communication when a plurality of temperature controllers are combined.

[0002]

2. Description of the Related Art A temperature instrumentation system using a temperature controller is disclosed, for example, in Japanese Patent Application No. Hei 4-3054 proposed by the present applicant.
No. 75 is disclosed. FIG. 6 is a configuration diagram of a temperature controller combined with a conventional general-purpose sequencer. The sequencer 10 has a digital output unit DO, a digital input unit DI, an analog output unit AO, and an analog input unit AI, and is connected to the signal input / output of the temperature controller 20. Here, AO is used for remote setting of operating conditions and the like for the temperature controller 20, AI is used for data transmission to the sequencer 10 side by a transmission function of the measured value PV of the temperature controller 20, and DI is used.
Is used for transmitting an alarm signal from the alarm output contact of the temperature controller 20 to the sequencer 10 side, and DO is used for the sequencer 10
Used to transmit a RUN / STOP switching signal from the side to the temperature controller 20.

According to such a configuration, the sequencer 10
Has the advantage that the data of each temperature controller 20 can be accessed directly, and the creation of a ladder program becomes easy. However, the sequencer 10 and each temperature controller 20
Both require DO, DI, AO and AI,
In addition, there is a problem that the number of cores of the signal lines connected to each other increases and the cost increases. In addition, when analog transmission is used, a setting error and a reading error are inherent, so that there has been a problem that high-precision data transmission becomes difficult.

FIG. 7 is a configuration diagram of a temperature controller combined with another general-purpose sequencer. The serial communication unit 11 is attached to the sequencer 10, and data exchange with the temperature controller 20 is performed by serial communication such as RS-232 and RS-422 via the communication line 30. On the temperature controller 20 side, the communication line 30 is connected in a multi-drop connection terminating at each branch. And according to such a configuration,
Since it is only necessary that both the sequencer 10 and each temperature controller 20 have a one-port serial communication function, there is an effect that the communication line is simplified.

[0005]

However, when the serial communication unit 11 is attached, the sequencer 10 cannot handle the data of the temperature controller 20 by the ladder program. Therefore, there is a problem that it is necessary to handle a high-level language such as BASIC having a communication interface function, and it is necessary to attach an expensive function to the sequencer 10. For such a request, for example, a set value is sent from the sequencer side to each temperature controller 20 and
This occurs when a readback is performed to confirm whether the set value is correctly set in each temperature controller 20.

An object of the present invention is to solve the above-mentioned problems, and an object of the present invention is to provide a temperature controller capable of exchanging data with a sequencer by serial communication and transmitting and receiving data by a ladder program on the sequencer side. I do.

[0007]

According to the present invention to achieve the above object, the present invention is connected to a sequencer 10 via a communication line and sent from the sequencer to a temperature controller in which an address 26 is defined. A data receiving unit 21 for receiving the setting data RD for the temperature controller at each address, a data storing unit 22 for selecting and setting data addressed to the own address from the received setting data, After a delay time that increases in response to the own address, a transmission delay activation unit 23 that activates the data reading unit, and in response to activation of the transmission delay activation unit,
A data reading unit for reading the received data stored in the data storage unit; and a data transmitting unit for transmitting the data read by the data reading unit to the sequencer as transmission data SD. The delay time is characterized in that the delay time is set to be longer than a normal time required for the temperature controller of the adjacent address to send out transmission data.

[0008]

The data receiving unit and the data transmitting unit are generally used for serial communication using a communication line. Since a plurality of temperature controllers are connected to the communication line, unique addresses are respectively defined. Then, the data storage unit recognizes and captures the address addressed to the own station based on the address, which is useful for the operation as a temperature controller. The transmission delay activation unit secures a delay time according to the address,
Avoid communication conflicts when temperature controllers at other addresses are using the communication line. The data reading unit sends the data to be transmitted this time to the data transmitting unit and cooperates with the read back of the sequencer.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the drawings. FIG. 1 is a configuration block diagram showing one embodiment of the present invention. In the figure, a temperature controller 20 is connected to a sequencer 10 via a communication line including a transmission line and a reception line. The address 26 is used to identify the temperature controller 20, and a unique value is given from a plurality of the temperature controllers 20 connected to the communication line. The data receiving unit 21 receives the setting data RD for the temperature controller 20 at each address, which is sent from the sequencer 10. The data storage unit 22 selects data addressed to the own address from the received setting data, and sets a set value and a measured value, which are necessary data for the control unit 27. The control unit 27 controls the temperature of a controlled object such as an electric furnace to a set value, and executes a control amount for an operation terminal such as a heater by PID control calculation or the like based on information of a detection terminal such as a thermocouple. .

After receiving the data, the transmission delay activation unit 23 activates the data reading unit 24 after a delay time that gradually increases in accordance with its own address. Here, the gradually increasing delay time is determined to be longer than the normal time required for the temperature controller 20 of the adjacent address to transmit the transmission data, and is set to a value obtained by multiplying, for example, 50 msec by the address 1 to n. The data reading unit 24 facilitates the reception data received by the data reception unit 21 in response to the activation of the transmission delay activation unit 23. For example, the data reading unit 24 reads the reception data stored in the data storage unit 22. The data transmission unit 25 includes the data reading unit 2
The transmission data SD read in step 4 is sent to the sequencer 10. As a result, the sequencer performs readback to compare the transmitted data with the received data,
You can check if the communication was successful.

FIG. 2 is a block diagram of an instrumentation system combining a sequencer and a temperature controller. The communication module of the sequencer 10 has transmission terminals SDA and SDB connected to a two-wire transmission line, and reception terminals RDA and RDB connected to a two-wire transmission line. Each temperature controller 20 has a receiving terminal RDA, R
DB and transmission terminals SDA, SD connected to the transmission line
B. Then, the sequencer 10 transmits the data to each temperature controller 20. Each temperature controller 20
Returns the readback information to the sequencer 10, but since there is only one transmission line, the transmission delay activation unit 23 works effectively to avoid contention of communication, and sequentially returns the readback information.

FIG. 3 is an overall configuration diagram of the communication system.
In the ladder program of the sequencer 10, a data copy unit for copying data to the transmission register 12 of the communication module 11, a transmission request relay 13 and a transmission completion relay 14
A transmission flag on unit for instructing the start of transmission by operating
It has a reception completion flag on unit for recognizing the reception completion by operating the reception request relay 16 and the reception completion relay 17, and a data copy unit for copying the data stored in the reception register 15 to the sequencer main body.

Since the eight temperature controllers 20 are connected to the transmission line in the transmission register 12, setting data is stored for each of the addresses 1 to 8 correspondingly.
The setting data transmitted to each temperature controller 20 is a set of three types: mode data, setting values, and manual output. The mode data specifies whether the operation of the temperature controller 20 is performed automatically or manually. Here, a 4-digit numerical sequence is used, where "0000" indicates the automatic mode and "0001" indicates the manual mode. The set value gives a control target value of the temperature controller 20. Here, the set value can be set in units of one degree using a 4-digit numerical sequence. The manual output is a set value when the manual is specified in the mode data. Here, the manual output is specified in 0.1% units using a four-digit number. However, when the automatic mode is selected, "0000" is set. It has become. These setting data are transmitted in the order of each address by the transmission flag ON section, and "CR, LF" indicating the end of data is transmitted last.

That is, the transmission flag on section first turns on the transmission request relay 13. Then, the transmission request relay 13 sequentially transmits the data stored in the transmission register 12, and when "CR, LF" is transmitted, the data transmission ends, and the transmission completion relay 14 is turned on. Then, the transmission flag ON unit includes the transmission request relay 13 and the transmission completion relay 1
4 is turned off to end the transmission sequence.

The reception register 15 stores data sent from the temperature controller 20 at each address. This data is a status flag indicating the output state of the alarm signal and the control signal, and the set value and measured value PV of the temperature controller 20. Data is sent from each temperature controller 20 after the return delay time corresponding to the address has elapsed, and stored in the reception register 15. When "CR, LF" indicating the end of data is received, the reception completion relay 1
6 is turned on, and the data copy unit copies the contents of the reception register 15 to the internal register of the sequencer. When the copying is completed, the reception request relay 17 is turned on, and the reception module 11 is set in a reception waiting state. After that, the reception completion flag ON section includes the reception completion relay 16 and the reception request relay 1
7 are turned off, and the reception sequence is terminated.

FIG. 4 shows a sequence from the sequencer 10 to each temperature controller 2.
FIG. 4 is an explanatory diagram of transmission to 0. Here, eight temperature controllers 20 are connected to the transmission line, and addresses 1 to 8 are assigned from the side closer to the sequencer 10. Here, one transmission frame has 12 addresses in each address.
There are 8 sets of byte data, CR, LF indicating the end of data
Is added, so that the data length is 9
It is 8 bytes. In contrast, each temperature controller 2
In the case of 0, the instruction addressed to the own station is extracted from the communication frame sent from the transmission line. Assuming that the address of the temperature controller 20 is n, the cutout position of the mode data is 12x (n-1),
For example, for address 1, the cut-out position of the mode data is from 0, and the read mode data is "0000".
It has become. The set value cutout position is 12x (n-1) +4. For example, for the address 1, the set value cutout position is from 4, and the read set value is "0200". The manual output cutout position is 12x (n-1) +8. For example, for address 1, the manual output cutout position is from 8, and the read manual output is "0000". The temperature controller 20 stores setting data addressed to its own station in the data storage unit 22.

FIG. 5 shows a sequencer 1 from each temperature controller 20.
FIG. 4 is an explanatory diagram of transmission to 0. Temperature controller 2 for each address
0 stores the setting data fetched from the receiving line in the data storage unit 22, waits for the transmission delay activation unit 23 to time out, and sends out the status data, the setting value, and the PV value to the transmission line. The temperature controller at the last address adds "CR, LF" after its own data. Here, the time-up time is set in increments of 50 ms, and if the address is n, the time-up time will expire after 50 nms.

On the other hand, the communication module 11 stores data sequentially sent from the temperature controller in the reception register 15. When the data is sent from the temperature controller 20 at the final address, "CR, LF" is received. Therefore, the data reception is completed and the reception completion relay 16 is turned on to notify the ladder program. Then, the data is copied into the sequencer internal register by the data copy unit.

[0019]

As described above, according to the present invention, the data setting from the sequencer to the temperature controller is performed by the broadcasting method, and the communication from the temperature controller to the sequencer is provided with the transmission delay activation unit to provide time division. Since the synchronization is performed, there is an effect that a temperature controller capable of performing data communication with a simple configuration is provided. Also, on the sequencer side, each parameter of a plurality of addressed temperature controllers can be handled as an image located on a fixed position in the transmission / reception register, so using only a general-purpose communication module and a ladder program, There is an effect that a temperature instrumentation system capable of transmitting and receiving parameters of the temperature controller can be provided.

[Brief description of the drawings]

FIG. 1 is a configuration block diagram showing one embodiment of the present invention.

FIG. 2 is a configuration diagram of an instrumentation system combining a sequencer and a temperature controller.

FIG. 3 is an overall configuration diagram of a communication system.

FIG. 4 is an explanatory diagram of transmission from the sequencer 10 to each temperature controller 20.

FIG. 5 is an explanatory diagram of transmission from each temperature controller to the sequencer.

FIG. 6 is a configuration diagram of a temperature controller combined with a conventional general-purpose sequencer.

FIG. 7 is a configuration diagram of a temperature controller combined with another general-purpose sequencer.

[Explanation of symbols]

 Reference Signs List 10 Sequencer 11 Communication module 12 Transmission register 15 Receiving register 20 Temperature controller 21 Data receiving unit 22 Data storage unit 23 Transmission delay starting unit 24 Data reading unit 25 Data transmitting unit

Claims (2)

(57) [Claims] 1. A temperature controller connected to a sequencer (10) via a communication line and having an address (26) defined therein, wherein setting data for the temperature controller at each address sent from the sequencer. (RD), a data receiving unit (21), a data storing unit (22) for selecting and setting data addressed to the own address from the received setting data, and a data storing unit (22) corresponding to the own address after receiving the data. A transmission delay activating unit (23) for activating a data reading unit after a delay time which increases gradually, and a data reading for reading a set value and a measurement value (PV) of the own device in response to the activation of the transmission delay activating unit Unit (24), and transmits the data read by the data reading unit to the transmission data (S
D) a data transmission unit (2) to be transmitted to the sequencer.
5) The temperature controller wherein the step-up delay time is set to be longer than a normal time required for a temperature controller at an adjacent address to transmit transmission data. 2. A sequencer according to claim 1, wherein the transmission register transmits setting data (RD) for the temperature controller at each address, and stores data transmitted from the temperature controller at each address. Receiving register (15)
And a transmission data copy unit for copying the contents of the internal register to the transmission register, and turning on the transmission request relay (13) to transmit the contents of the transmission register to the temperature controller at each address, and transmitting after the transmission is completed. A transmission flag on section for turning on the completion relay (14), a reception completion flag on section for turning on the reception completion relay (16) when data transmission from the temperature controller of each address is completed, and the data stored in the reception register. A temperature instrumentation system, comprising: a reception data copy unit for copying data to an internal register; and a combination with the temperature controller according to claim 1.