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About MRPLC82

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  1. I have done some research today and found that COP instruction can not be used in this situation as it will pack two INT tags in one DINT tag.
  2. I could use OTE, that`s an option, I just though OTL would be more robust solution in case of PLC restart etc. I have got two conditions on rung 1 , when hour is greater than 11 and less 16 to OTE an output. This should work too. Going back to my OTL option, what was I doing wrong there, OTL and OTU were active at the same time - condition on rung were not permitting it .
  3. I want to energize it for few hours hence I decided to use OTL. In simple terms when there is 12:00:00 , OTL my output. Output should stay latched until on rung below PLC detects request to unlatch it at 16:00. I hope I explained it well.
  4. Evening, I struggle with simple task... I need to activate PLC Output at the specific time of a day. I`m using GSV to obtain PLC time, data is being moved to DIN[7] registers. Then I have three EQU (Hour / Minute / Second) and at the end of rung there is OTL for output. Rung below I have two EQU (Hour / Minute) to disable output at different time - OTU. However every time OTL is energised , OTU on rung below is fired too. What am I doing wrong here ?
  5. Michael, Many many thanks, you helped me a lot. After playing with PID yesterday I understand a lot more. 
  6. I need some advice how to tune PID properly. The PID is only PI type (two mode) and its overshooting frequently. Assuming I need to tune P with starting incrementing by very small steps till PID oscillates.  Once the P is established then will be tuning I , again with small increments till PV follows SP.  So this is my assumption below but would like someone to comment on it as I haven’t had to do it before , been learning PLC for 4 months now.  Do I need to start a machine and then start tuning PID or can this be done in more friendly way , offline ?