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Dear colleagues and siemens experts, I''m new in siemens. As all I make my program for PLC, but I need help with PID autotunig (pretuning) I use : 1.CPU 1214C DC/DC/DC (6ES7214-1AG40-0XB0) 2. 6ES7214-1AG40-0XB02. 16IN/16 OUT DC/DC/DC (6ES7-223-1BL32-0XB0) 3. 2x 6ES7231-5PD32-0XB0 ( 4 channel RTD analog module - PT100) We use 7(seven) Pt100 points with 7(seven) heaters ... so I need 7 additional outputs..... [you can see example of wiring in attached pic 6es7231-5pd32-0xb0-modules.jpg] Maximum heating point is around 220 degrees. I make my configuration for PID_Compact : 1. Basic settings 1.1 Controller type : Temperature : °C Set mode to : Pretuning ( sometimes I make it Automatic mode) 1.2 Input_Per(analog) -----> Output_PWM 2.Process value setting: 2.1 Process value limits: Process value high limit : 220.0 °C 2.2 Process value limits: Default 3. Advance setting 3.1Process value monitor : Default 3.2 PWM limits Minimum ON time : 0.5 sec Minimum OFF time : 0.5 sec 3.3 Output value : Default 3.4 PID parameters : Default I start Commissioning with these steps : 1. Measurement : Sampling time 0.5 Start 2. Start PID_Compact 3.Tuning mode : Start When I try first time my setpoint was 90 degrees , second time I try with 120 degrees. After 4-5 hours it stop more in Progress bar it stop when I reach a little more then 50%, and I stop PID. For heaters it is not normal to process to be 4-5 hours, there have some wrong. Example with 120 degrees : During process I make : When Input_PER reach 120[1200] degrees I stop physical access to heaters. When Input_PER reach 100[1000] degrees I start physical access to heaters So 4-5 hours is soo long time for this type process. Time to reach 120 degrees from 100 degrees is around 2-3 min. Time to fall from 120 degrees to 100 degrees is around 4-5 min. Total time for one whole cycle around : 8min. Sometimes when I set setpoint to 140, 150 degrees it writes me that output set value is to high after I give Start Pretuning ? Even sometimes when try for 120 degrees .... As all I want to start PID pretuning (autotuning) with setpoint 140 - 150 degrees. Which are minimum requirement to start PID autotuning with PID_Compact ? Could you send me some very simple example and steps that I must make or only steps ? I attached files in dropbox with images and program example, because I can't attached nothing here. This form don't give me access to attached something. So link is here : Even program is there. Thanks in advance Best regards : Altan

Hey, this may be an obvious question, but here goes: I have a CompactLogix L36ERM running RL5000 controlling one of our lead die cast machines. When I make a change to the program offline and need to download I always go and shut the machine down for safety reasons before downloading. One of our techs stopped the machine but left the control power and hydraulic pump on while downloading (something we are not supposed to do) when he finished downloading he switched it back to run mode and the machine closed on it's own and started right back up. This is a safety concern to me. We have a "close enable" tag that is true when all necessary conditions are met, and gets latched on when the machine is running in full auto. Before he downloaded the machine was at idle, meaning that the only way to close the machine would be to press the two dead-man switches to start the process. But, when he downloaded it started up automatically. Now I know the reason why is when the program was last saved, the "close enable" tag had a value of 1, it was latched on, so it bypassed the dead-man switches. A quick fix would be to save the program with that tag un-latched so that it can't start up on it's own after downloading. But, in case somebody saves the program while the machine is running and with that tag latched on, I need a better solution. Is there any tag or bit that goes true when a program is downloaded or when the mode of the PLC is switched from run to download to run? I want to manipulate that tag so that when I download it un-latches the "close enable" tag. I'm sure there is a way to do it, I'm just not even really sure what to search for in the online help. Any help is greatly appreciated. Thanks Howard

Hi all. I currently have a scenario where I connect with a SCADA (OPC using virtual com port) to an Controller (A-series) via E300 HMI using transparent mode. This setup works fine, no problems. I have now upgraded the E300 to the E1032 HMI with all the same settings, except the E300 was using an expansion Ethernet card and the E1032 is using the built-in Ethernet port. Now with the E1032 in place the SCADA (OPC) just cannot get healthy comms to the A series PLC. Am I missing something somewhere?