CN205540234U - Band conveyer protects end system - Google Patents

Abstract

The utility model belongs to the field of industrial control, in particular to a belt conveyor protection terminal system. Including the signal input terminal connected to the protection sensor, the output terminal of the signal input terminal is connected to the input terminal of the protection terminal unit; the output terminal of the protection terminal unit is connected with the controller unit, the controller and the acquisition terminal through the communication output mode and/or the analog output mode respectively. The input end of the card unit is connected; the other input end of the controller unit is bidirectionally connected with the output end of the computer. The communication output rules of the RS-485 interface of the MODBUS communication protocol are used to transmit various protection signals to the controller unit. This communication method only needs one communication interface to complete the transmission of protection signals, and has high efficiency and anti-interference ability Strong; use the analog signal 4‑20mA communication output rule to transmit various protection signals to the controller and acquisition card unit. This communication method only needs a quarter of the channel to transmit signals, which greatly reduces industrial investment costs. .

Description

A belt conveyor protection terminal system

technical field

The utility model belongs to the field of industrial control, in particular to a belt conveyor protection terminal system.

Background technique

In industrial production, the belt conveyor is the main transportation equipment in industrial production, and the operation status of the belt conveyor directly affects the daily industrial production. When the belt conveyor is used, various sensors for the protection of the belt conveyor will be installed, such as pull rope switches, deviation sensors, tear sensors, coal pile sensors, etc. The output of these sensor signals is generally in the form of passive contacts. That is, switch output.

The traditional belt conveyor protection device directly connects the output signal of the protection sensor to the PLC or DCS controller supporting the RS-485 MODBUS protocol of the industrial production centralized control system, which not only occupies a large number of switching input channels, but also Greatly increased the cost of investment.

Utility model content

In order to overcome the shortcomings of the prior art, the utility model provides a belt conveyor protection terminal system. The utility model occupies a very small number of switch input channels, which greatly reduces the industrial investment cost.

In order to achieve the above object, the utility model adopts the following technical measures:

A belt conveyor protection terminal system, including a signal input terminal connected to a protection sensor, the output end of the signal input terminal is connected to the input end of a protection terminal unit;

The output end of the protection terminal unit is connected to the input end of the controller unit, the controller and the acquisition card unit respectively through a communication output mode and/or an analog output mode;

The other input end of the controller unit is bidirectionally connected with the output end of the computer.

The utility model can also be further realized through the following technical measures.

Preferably, the communication output mode adopts the communication output rules of the RS-485 interface of the MODBUS communication protocol.

Preferably, the analog output method adopts the communication output rule of 4-20mA analog signal.

Preferably, the communication output of each analog signal 4-20mA is combined by 8421 codes.

Preferably, the protection terminal unit includes an interface circuit, the interface circuit is provided with a circuit for attenuating the input signal from the signal input terminal and a circuit matched with a capacitor; the output terminals of the interface circuit are respectively connected to the controller Unit, controller and the input end of the acquisition card unit.

Further, the baud rate of the RS-485 interface is set to 9600bps, and the communication parameter is RTU mode.

Further, the voltage of the input interface of the signal input terminal is set to an AC voltage of 220V.

Further, the output end of the protection sensor is connected to the input end of the signal input terminal through a cable.

The beneficial effects of the utility model are:

1), the utility model enters the protection terminal system after processing various protection signals of the protection sensor through the interface circuit, and processes various protection signals inside the protection terminal unit, and at the same time, the protection signals are output through communication and/or analog The output mode is output, and various protection signals are transmitted to the controller unit by the communication output rule of the RS-485 interface of the MODBUS communication protocol. This communication mode only needs one communication interface to complete the transmission of the protection signal, and the efficiency High, strong anti-interference ability; use the analog signal 4-20mA communication output rule to transmit various protection signals to the controller and the acquisition card unit, this communication method only needs a quarter of the channel to transmit signals, greatly Reduced industrial investment costs.

2), the output end of the protection sensor is connected to the input end of the signal input terminal through a cable, and the voltage of the input interface of the signal input terminal is set to 220V AC voltage, which is convenient for the collection and transmission of various protection signals on site.

Description of drawings

Fig. 1 is a schematic diagram of the utility model;

Fig. 2 is the corresponding relation between the data of the present utility model and the signal input terminal;

Fig. 3 is the corresponding relationship between the signal input terminal and the analog output terminal of the present utility model;

Fig. 4 is the work flowchart of the present utility model.

The meanings of the reference signs in the figure are as follows:

10—signal input terminal 20—protection terminal unit

21—Interface circuit 31—Controller unit

32—Controller and acquisition card unit

detailed description

The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. example. Based on the embodiments of the present utility model, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the scope of protection of the present utility model.

As shown in Figure 1, a belt conveyor protection terminal system includes a signal input terminal 10 connected to a protection sensor, the output end of the signal input terminal 10 is connected to the input end of a protection terminal unit 20;

The output terminal of the protection terminal unit 20 is connected to the input terminal of the controller unit 31 through the communication output rule of the RS-485 interface of the MODBUS communication protocol, and the output terminal of the protection terminal unit 20 is also output through the communication of the analog signal 4-20mA The rules are connected to the input of the controller and the acquisition card unit 32;

The other input end of the controller unit 31 is bidirectionally connected with the output end of the computer.

The protection terminal unit 20 includes an interface circuit 21, and the interface circuit 21 is provided with a circuit for matching resistance and capacitance for attenuating the input signal from the signal input terminal 10; the output terminals of the interface circuit 21 are respectively connected to The input end of the controller unit 31 , the controller and the acquisition card unit 32 .

When the utility model is in use, it can be used in cooperation with the software in the prior art. The working principle of the utility model is described below in conjunction with the software in the prior art, but it must be pointed out that: the software matched with the utility model is neither an innovative part of the utility model nor an integral part of the utility model.

Design of communication output mode: set the baud rate of the RS-485 interface to 9600bps, and the communication parameters to RTU mode; the substation address of the belt conveyor protection terminal system defaults to 1, which is 01H; let the computer read the belt conveyor Protects the data format of the end system.

When the host command is: MMH 03H 00H 01H 00H 01H CLH CHH

Belt conveyor protection terminal system response: MMH 03H 02H YYH YYH CLH CHH

Among them, MMH～the substation address of the belt conveyor protection terminal system, the default is 01H;

CLH～MODBUS communication protocol CRC check low 8 bits;

CHH～MODBUS communication protocol CRC check high 8 bits;

YYH～the response data of the belt conveyor protection terminal system.

As shown in Figure 2, in the corresponding relationship between the signal input terminal 10 and YYH of the belt conveyor protection terminal system, N represents the common terminal of the signal input terminal 10, and the belt conveyor protection terminal system collects at least 16 switch input signals, the first A digital input signal corresponds to the D1 terminal, and its signal state is indicated by the bit 0 of the data YYH, that is, when the D1 terminal collects the belt conveyor protection signal, the state of the YYH bit 0 becomes 1, and when the D1 terminal does not collect the belt conveyor When protecting the signal, the state of bit 0 of YYH becomes 0; similarly, the principles of other terminals are the same.

D5 and D11 respectively collect the action signal of the protection terminal system of the belt conveyor, the state of YYH corresponding to bit 0 and bit 2 changes to 1, and the binary data is converted into hexadecimal to 04H 10H, that is, the protection terminal unit 20 turns on the encoding mode , when the controller unit 31 receives the response data from the protection terminal unit 20, it converts the response data from hexadecimal to binary, that is, the decoding mode.

Design of analog output mode: the analog output mode adopts the communication output rule of analog signal 4-20mA. In order to show the state of discrete input signal and its combined signal state, four analog 4-20mA signals are designed. Output, each analog 4-20mA signal output is combined by 8421 codes, which characterizes the state of the four discrete input signals and the state of the combined signal. Table 1 shows the 8421 combination of four discrete input signals, and Table 2 shows the four Discrete input signal 4-20mA truth table.

Table 1

Table 2

As shown in Figure 3, each group of discrete input signals of the belt conveyor protection terminal system is An, Bn, Cn, Dn, where n=1, 2, 3, 4, which correspond to AO1, AO2, AO3, AO4 respectively Group analog output, discrete input signal has 16 state combinations, each state combination follows the 8421 code rule, the output current is 0-15mA, in order to meet the national standard 4-20mA signal, set the initial output current to 4mA, so each The analog quantity corresponding to a group of discrete input signals is 4-19mA, and different output currents represent different input signals and combinations of input signals. Four discrete input signals form a group, a total of four groups of 16-point discrete input. When the 4-20mA signal outputs the analog quantity, the groups are independent from each other. Therefore, the communication output rule of analog signal 4-20mA is used to transmit various protection signals to the controller and the acquisition card unit. This communication method only needs a quarter of the channel for signal transmission, which greatly reduces the industrial investment cost.

As shown in Figure 4, first initialize the MODBUS communication parameters and analog output. If the signal input terminal 10 corresponding to the belt conveyor protection terminal system has an external signal, that is, when the level is high, the protection signal is processed by the interface circuit 21 and then enters the internal circuit. At the same time, the corresponding bit storage area in the software is set to 1. If the external signal becomes low level, the corresponding bit storage area is set to 0, that is, the state of the bit storage area follows the state of the external signal, that is, the state of the bit storage area represents the external signal state, the protection terminal unit 20 calculates and processes the data in the bit storage area according to the MODBUS communication rules, and waits for the computer request command connected with the controller unit 31, and the belt conveyor protection terminal system returns corresponding response data according to the request command; at the same time , according to the 4-20mA communication output rules, calculate 4 sets of digital quantities that need to be output, and convert them into corresponding 4-20mA outputs through D/A.

Claims (8)

1. A belt conveyor protection terminal system, characterized in that: comprise a signal input terminal (10) connected to a protection sensor, the output end of said signal input terminal (10) is connected to the input end of a protection terminal unit (20); The output end of the protection terminal unit (20) is respectively connected to the input end of the controller unit (31), the controller and the acquisition card unit (32) through a communication output mode and/or an analog output mode; The other input end of the controller unit (31) is bidirectionally connected with the output end of the computer. 2. A kind of belt conveyor protection terminal system as claimed in claim 1, characterized in that: said communication output mode is the communication output rule of RS-485 interface using MODBUS communication protocol. 3. A belt conveyor protection terminal system as claimed in claim 1, characterized in that: the analog output mode is a communication output rule using an analog signal of 4-20mA. 4. A belt conveyor protection terminal system as claimed in claim 3, characterized in that: the communication output of each analog signal 4-20mA is combined by 8421 codes. 5. A kind of belt conveyor protection terminal system as claimed in claim 1, is characterized in that: described protection terminal unit (20) comprises interface circuit (21), is provided with in the described interface circuit (21) A circuit in which the input signal of the signal input terminal (10) is attenuated by a resistor and a capacitor; the output end of the interface circuit (21) is connected to the input of the controller unit (31), the controller and the acquisition card unit (32) respectively end. 6. A belt conveyor protection terminal system as claimed in claim 2, characterized in that: the baud rate of the RS-485 interface is set to 9600bps, and the communication parameter is RTU mode. 7. A belt conveyor protection terminal system according to claim 1 or 4, characterized in that: the voltage of the input interface of the signal input terminal (10) is set to an AC voltage of 220V. 8. A belt conveyor protection terminal system according to claim 1, characterized in that: the output end of the protection sensor is connected to the input end of the signal input terminal (10) through a cable.