EC20 PLC在老化房控制系统中的应用，以及该产品PID闭环功能在恒温控制上的实现和强大的网络通信功能对艾默生EV2000的变频器运行控制。实现了对室内温度和变频器运行的集中控制。 EC20 PLC在老化房控制系统中的应用并着重介绍该产品的PID闭环功能在恒温控制上的实现和强大的网络通信功能对EMERSON EV2000变频器运行控制的实现。该老化房控制系统是家电，电子，电脑行业产品生产检测的重要设备，也是产品生产合格检查的重要环节。该系统采用EMERSON EC20 PLC和多台EV2000变频器，实现对室内温度和变频器运行的集中控制。
The application of EC20 PLC in the control system of aging room, the realization of PID closed-loop function in constant temperature control and the strong network communication function of the product control the operation of Emerson EV2000 converter. The centralized control of indoor temperature and frequency converter operation is realized. The application of EC20 PLC in the control system of aging room and the realization of PID closed-loop function in constant temperature control and strong network communication function in EMERSON EV2000 frequency converter operation control are emphatically introduced. The aging room control system is an important equipment for the production and inspection of household appliances, electronics and computer industries, and also an important link for the product production qualification inspection. The system uses EMERSON EC20 PLC and several EV2000 frequency converters to realize centralized control of indoor temperature and frequency converter operation. 二、 老化房控制系统工艺要求
II. Process Requirements for Control System of Aging Room
具体要求如下：
Specific requirements are as follows:
1, 该系统所控制的老化房面积达16×30M，要求控制范围在20-55℃，控制精度达±5℃，能够在上位机对温度设定/显示/保存；（加湿控制采用单独进行和PLC无关）
1. The area of the aging room controlled by the system is 16 *30M, which requires the control range of 20-55 C and the control precision of <5 C. The system can set/display/save the temperature on the host computer; (The humidification control is independent of PLC.)
2, 该系统有3个风机，用于进风，回风和排风；有4个风闸：新风闸，回风闸，排风闸，防火闸；2个防尘过滤网；6个火灾报警点；
2. The system has three fans for air intake, return and exhaust; four air gates: fresh air gate, return air gate, exhaust air gate, fire gate; two dust-proof filters; six fire alarm points;
在正常情况下（温湿度），关闭进风阀和排风阀，停止进风电机和排风电机，打开回风阀和防火阀，启动回风风机，保持老化房内回风循环；
Under normal conditions (temperature and humidity), close the intake valve and exhaust valve, stop the intake motor and exhaust motor, open the return valve and fire valve, start the return fan, and maintain the return air circulation in the aging room.
在高温情况下，排风阀和进风阀打开，启动排风电机和进风电机，抽出部分空气；
At high temperature, the exhaust valve and the intake valve are opened, the exhaust motor and the intake motor are started, and part of the air is drawn out.
在火灾报警情况下，防火阀关闭，回风禁止循环，全部从室内抽出；同时排风阀和进风阀打开，启动排风电机和进风电机，抽出室内空气；
In the case of fire alarm, the fire valve is closed, the return air is forbidden to circulate, and all the air is drawn out from the room. At the same time, the exhaust valve and the intake valve are opened, and the exhaust motor and the intake motor are started to extract the indoor air.
三、工作原理：
3. Working Principle:
根据老化房工艺要求组成如上图控制系统：上位机采用台湾研华IPC（工控计算机）；监控画面采用亚控公司的KINGVIEW软件，该软件操作简单，元件形象丰富，性能稳定；核心控制部分采用EMERSON EC20-2012BTA类型的PLC和4个温度采集模块（EC20-4TC，接受K型温度信号）；传动采用EMERSON EV2000通用型变频器。
According to the technological requirements of the aging room, the control system is composed as follows: the upper computer adopts Taiwan Yanhua IPC (industrial control computer); the monitoring screen adopts KINGVIEW software of sub-control company, which has simple operation, rich component image and stable performance; the core control part adopts EMERSON EC20-2012 BTA type PLC and four temperature acquisition modules (EC20-4TC, which receives K-type temperature signal); EMERSON EV2000 universal frequency converter is used.
在设备连接方面，EC20 PLC充分体现了自身的优势，由于EC20 PLC本身带有2个串行通信口（1个RS232口，集成自由协议/编程协议/MODBUS从站协议，1个RS232/485口，集成自由协议/MODBUS主站/从站协议），EC20 PLC利用COM0口和IPC进行通信（EC20 PLC做从站，设置成MODBUS从站协议），利用COM1和多台变频器组成网络进行集中控制（EC20 PLC的COM1设置成MODBUS主站协议）。
In terms of equipment connection, EC20 PLC fully embodies its own advantages. Because EC20 PLC itself has two serial communication ports (one RS232 port, integrated free protocol/programming protocol/MODBUS slave protocol, one RS232/485 port, integrated free protocol/MODBUS master/slave protocol), EC20 PLC communicates with IPC using COM0 port (EC20 PLC as slave station, set up as MODBUS slave station protocol), EC20 PLC has advantages. COM1 and several inverters are used to form a network for centralized control (COM1 of EC20 PLC is set as MODBUS master station protocol).
IPC为整个系统的人机接口，IPC读取PLC采集的系统运行状态如各风机的运转状态，各测温点温度，报警状况并显示在监控画面上，IPC又把各种操作命令传给PLC以控制系统的运行，如温度的设定，PID参数设定，各种阀门的开闭，变频器的启动、停止等设定。并且可以实时监控整个系统的工作运行状态、动作过程及故障报警等，IPC还可以根据设定对采集的数据进行保存打印。
IPC is the man-machine interface of the whole system. IPC reads the operation status of the system collected by PLC, such as the operation status of each fan, temperature of each temperature measuring point, alarm status and display on the monitoring screen. IPC transmits various operation commands to the PLC to control the operation of the system, such as temperature setting, PID parameter setting, valve opening and closing, frequency converter starting and stopping, etc. And it can real-time monitor the working state, action process and fault alarm of the whole system. IPC can also save and print the collected data according to the setting.
在系统设计中，EC20 PLC为整个系统的核心，执行各种系统操作及计算，EC20 PLC根据工艺要求和现场状况进行逻辑判断，开闭各种阀门和启停各风机；同时利用自身的PID功能对温度进行控制，具体方法后面描述。
In the system design, EC20 PLC is the core of the whole system. EC20 PLC carries out various system operations and calculations. EC20 PLC makes logical judgments according to process requirements and site conditions, opens and closes various valves and starts and stops various fans. At the same time, it uses its own PID function to control temperature. The specific method is described later.
EV2000系列变频器自带RS485接口的通讯单元，符合RS485通讯规范，用于实现PLC与多台变频器的联网。根据MODBUS通讯协议，我们可以通过RS485网络轻松实现对变频器的运行控制。由于RS485通讯链路传输距离远、配线简单、抗干扰能力强、可靠性高，因此在设计中，我们省略了变频器的外部起停控制线路，对变频器的所有控制都通过RS485通讯链路来完成，达到了经济高效的目的。
The communication unit of EV2000 series frequency converter with RS485 interface conforms to RS485 communication specification, and is used to realize the interconnection of PLC and multiple frequency converters. According to MODBUS communication protocol, we can easily control the operation of frequency converter through RS485 network. Because of the long transmission distance, simple wiring, strong anti-interference ability and high reliability of RS485 communication link, we omitted the external start-stop control circuit of frequency converter in the design. All the control of frequency converter is accomplished through RS485 communication link, which achieves the goal of economy and efficiency.
