Take the following steps to execute run/stop commands.
(1)Select Operation - Run/Stop Command from the Execute Menu. The following dialog box will appear.
(2)Select Hot Start to hot-start the Loop Control Unit/Board. Select Cold Start to cold-start the Loop Control Unit/Board.
(3)Click the Execute Button. HOT START or COLD START will appear in the Run Status Field. (4)To stop operating the Loop Control Unit/Board, select Stopped and click the Execute Button. NOTE: When ERROR CODE is displayed for the opeating condition, check the communication condition.
Check the following items before operating the Loop Controller.
Make sure the Analog I/O Units used with the Loop Controller are properly mounted.
Make sure the unit numbers on the front panel of the Analog I/O Units coincide with the unit numbers set in the Field Terminal Function Blocks. Data for another Special I/O Unit will be read and written if an incorrect unit number is used.
Make sure the initial settings in the System Common Block in the Loop Controller are correct. Check that the DM Area words for the Node Terminal Function Block in the CPU Unit of the Loop Control Unit will not be used for any other purpose.
Starting/Stopping Loop Controller Operation (All Function blocks)
There are three ways of indicating run/stop of the Loop Controller (common to all function blocks) when the PLC power is turned ON.
(1)By operating CX-Process Tool (Both run start and stop can be specified.)
(2)By issuing the FINS WRITE ITEM commands (command codes 0241 and 0243 Hex) to change ITEM014 (run/stop command) of the System Common block (Block Model 000)(Both run start and stop can be specified.)
(3)By changing ITEM014 (run/stop command) of the System Common block (Block Model 000) by the ITEM Setting blocks (Block Models 171 and 172). (Only run stop can be specified.) NOTE:
a) ITEM014 of the System Common block cannot be set to 1 (hot start) or 2 (cold start) by ITEM Setting blocks. Only 0 can be set.
b) Setting to a hot start or cold start is not accepted if these modes are instructed while the Loop Controller is already running.
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c) ITEM014 (run/stop command) of the System Common block (Block Model 000) cannot be changed directly by the Step Ladder Program block (Block Model 301). It is changed via the ITEM Setting blocks.
Stop/Start Block Operation
Each Function block operation can be stopped or started. Use any of three procedures written below:
Operation from CX-Process Tool (In Block Diagram Validate Action Mode. Both of Stopping and Starting)
Send FINS Command, Write ITEM Command (Command Code 0241/0243Hex) to change the value in ITEM000 (Stop blockoperation). (Both of Stopping and Starting)
HMI Function
It is not possible to start the operation of each Function block in Cold start by resetting operation stop. The operation is started in Hot start mode.
Hot Start and Cold Start Hot Start
Use the Hot start mode when it is preferable to continue operations after a short power interruption, or it is necessary to use the same Remote/Local setting, MV output value, and Auto/Manual setting that existed before the power went OFF.
Hot starts are not performed and cold starts are performed after power interruption of 24 hours. Cold start
When operation is started in Cold start mode, the memory area used for operations, as well as the MV output, Auto/Manual switch, and Remote/Local switch settings are initialized when the Loop Controller is restarted. (PID block restarts operation in Manual mode, with MV=0% and Local SP). Use the cold start mode when it is not necessary to continue operation with the same values that existed before the power was turned OFF and it is acceptable for the controller to start operation with the following settings: Local SP, MV = 0, and Manual mode.
2. System Operation Check
It is possible to monitor or control the status of System Common Block of the Loop Controller. The following items can be monitored or controlled. This function is mainly used for checking the load rate or execution errors.
Monitor items:Present load rate, maximum load rate, operation cycle automatic change flag, mini- mum block address with an execution error, execution error code of each block address, block ad- dress with a database error, battery error, and ITEM data for System Common Block.
Control items:Maximum load rate and resetting operation cycle automatic change flag.
Check the system operation of created Function block data on CX-Process Tool before starting actual operation. Especially check if load rate of the Loop Controller is 80% or less. (Refer to
Appendix3-6 Load Rate of the Loop Controller for detailed infotmation about load rate).
Take the following steps to monitor the run status of System Common Block of the Loop Control- ler.Select Operation - Monitor Run Status from the Execute Menu. The dialog box below will ap- pear.
Operating condition of the Loop Controller system is displayed under the Data Name column. The values under the Data column are recorded when the Monitor Run Status Dialog Box is
opened.
To refresh the data with the dialog box displayed, click the Refresh Button.
To execute the ITEM displayed under the Run column, select the ITEM and click the Execute Button.
For a Loop Controller, the processing time load rate/maximum control load rate indication (Loop Controller's load rate/maximum load rate) for the overall Loop Controller for each oper- ation cycle block (e.g., ITEM 047/ITEM 048), are indicated in1% units. The data range is 0 to 100 (unit: 1%).
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ITEMs Marked "Reset"
ITEMs remarked Reset can be set to 0 (reset). Select the ITEM and click the Execute Button. The following dialog box will appear. Click the OK Button.