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Live demo of how to control a 3-Phase AC motor using a GS1 series drive and a CLICK PLC.
In this video I'll be showing you how to control a motor using the CLICK PLC and the GS1 drive. We'll assume that you have already wired the motor and drive correctly, and have already entered all of the required motor nameplate parameters into your drive. If you haven't done that please refer to chapter 3 in the GS drive manual before continuing with the video. Now, we need to setup the GS1 drive for MODBUS communication. First we need to make the drive controllable through MODBUS, so we'll set parameter 3.00 to 3 this sets the source of operation to be determined by the RS-485 interface. Parameter 4.00 needs to be changed to 5, which tells the drive that the source of frequency will be determined by the RS-485 interface. We need to change the communication address, which is parameter 9.00. You can set the address to any slave address you like, I'll choose 2. We need to change parameter 9.01, which is the transmission speed to 2, this sets the baud rate to 19,200. Parameter 9.02 is the communication protocol. We want MODBUS RTU, 8 data bits, odd parity, and 1 stop bit; so we need to change it from 0 to a 5. So now that the GS drive is setup we can move on to setting up the PLC. Now in the CLICK software we need to configure the com port. To get to the setup menu go to setup and then com port setup. For this demonstration I'm running a cable from the RS-485 port on the CLICK to the RS-485 on the drive. You can find the cable on Automation Direct's website. So go ahead and click on setup. Make sure the Node Address is set to 1 because we want the PLC to be the master not the slave. Change the Baud Rate to 19,200; make sure the Parity is set to odd, and make sure the stop bit is set to 1. Once, you are done entering that go ahead and hit ok and then ok again. To test the connection we'll turn the motor on and set the frequency for it to run at. First we need to add an edge contact onto the first rung. Go ahead and type in C7, we need to add another edge contact on the second rung. Type in C8. In the coil area of the first rung we want to set the frequency for the motor to run at, so drag in a send command. Make sure the com port matches the one that you are using. Change the slave id to whatever you had set in the GS drive. Change the Modbus Function code to 06 - Write Single Register. Leave the Addressing Type alone for now. Now we need to put in a slave address. You can find all the slave addresses for the GS drives in the manual under chapter 5. For our example, we want to write a new value into a register in the GS drive. The slave address in the GS drive that we want to write to is 2331. With MODBUS addressing we must include a function code at the beginning of the request. The function code relates to a certain register type. A 0 relates to Coils, a 1 relates to Input Bits, a 3 relates to Input Registers, and a 4 relates to Holding Registers. So, while the desired address is actually 2331, we have to put a 4 in front to denote it as a holding register. And because CLICK requires it to be a six digit number we need to put a 0 after the Function Code and before the desired address. The starting master address is asking you which variable do you want to write to the holding register that you've defined. You can pick any variable you want, I'll go ahead and choose DS1. The status flags are used to let you know the condition of the command. You can set these to whatever you want. I'll set Sending as C1, Success as C2, Error as C3, and Exception Response to DS3. When the command is sending, C1 will energize; when the command is successful, C2 will energize; if there was an error during the command, C3 would energize. If you do get an error you can view the value stored in the tag that you had set for the Exception Response value. The error code will be stored in that variable. We are all done in the receive command and you can go ahead and hit ok. In the coil area of the second rung we want to tell the motor to run, so drag in another send command. Make sure that the com port matches the one you are using. Change the slave id to whatever you had set in the GS drive. Make sure the Modbus Function code is set to 06 - Write Single Register. Leave the Addressing type alone. In the slave address we need to put 402332. Put DS2 in the starting master address and I'll set Sending as C4, Success as C5, Error as C6, and Exception Response as DS4 Don't forget to add your end statement, and then go ahead and download the program to the PLC. Go ahead and open up the data view window by double clicking. And then add the following tags; DS1, DS2, C7, and then C8. DS1 is the frequency for the motor to run at. DS2 is the stop or start command. C7 sends the frequency to the drive. And then C8 sends the run or stop command to the drive. So for the frequency we'll set that as 200. And then for DS2, which is the run or stop, we'll set as 1. And then we'll double click under the write column which sends the value to the PLC. Also do that for DS2. Then we'll double click on on for C7 and then double click off. And then once we double click on for C8 the motor will start running. And sure enough we can see the motor is running. This was a very simple example of what the CLICK and the GS drive are capable of. Now that you know how to send and receive data between the CLICK and the GS drive the possibilities are endless.