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  1. grounding and fluctuation

    Hi All , Thanks for all the reply and help.  let me try as what u said. And thanks for sharing the video.    
  2. grounding and fluctuation

    HI  BOB,  "What is the analogue signal - 4-20ma? 0-10V? 4-20ma is much better for noise rejection - I will not use voltage analogues at all! Is the 24VDC supply negative grounded? That is always a no no as far as I am concerned - do not ground the negative at all but let it float - ground noise introduced. I expect the 24VDC supply is from a switch mode power supply. If so what brand? There is some really cheap junky stuff out there. Is the analogue cable only grounded at one end? It should be grounded at the source only.  "   Based on red coloured statement how can i do wiring ? Something as below pic?    
  3. Add Delay to to the Analogue out

    Hi Chelton,  thanks a lot.
  4. Add Delay to to the Analogue out

    Hi ,    I already extended FB areas of H-memory. Is there any issue if I change my over all FB memory allocation to d10000 ? Mean while I will try the feasibility of using IN-OUT  method.    
  5. Add Delay to to the Analogue out

    HI,  Its tested and working well. I have 8 Analogue inputs and will be using 8FBs, which need 800 words for Buffer_Ring array. But i don't have much free words in H-memory for Buffer_Ring array.  Is there any way that i can assign  Dmemory for the array? ( Assign "AT" in the Fb variable session not possible as this FB is using simultaneously for different Analogue inputs)    
  6. Add Delay to to the Analogue out

    hi Chelton. Thanks a lot. Let me go thru and work it out.
  7. Add Delay to to the Analogue out

    thanks  It seems like a code for FB.   Could you please specify the input,output and internal variables and data type? I managed to identify some. EN (bool) ------>INPUT Run (Bool)------>INPUT Ring_Buffer_Initialize (bool) Ring_Buffer_Write_Index Ring_Buffer_Read_Index Ring_Buffer_Size Ring_Buffer_Read_Index RB-Loaded (bool)------>OUTPUT ONS_Trig (bool)------>OUTPUT Ring_Buffer[ ] ------>INTERNAL Analogue_In (UINT)------>INPUT  Analogue_Out(UINT) ------>OUTPUT Appreciate all your help Regards, T J sharon
  8. Add Delay to to the Analogue out

    hi Chelton, Mostly 1-5 seconds delay.   Do you have any sample prgm?  
  9. Add Delay to to the Analogue out

    Hi all,    I have an FB (ST) which will calculate the UINT values that need to send to DA outputs. Currently i was requested to add a delay between the calculated output & DA units. I am not sure how to do it? can I just use a TON? Any sample ST code?  
  10. Unable to Recieve data from RS485 in protocol macros

    Hi all,  I managed to wrote the response data strings to data memory. What i did was ,I changed the send and receive message data bit from 'variable Hex' to 'variable' in the CX Protocol file.  Now its working. I tried different combinations of send and receive messages. All worked well . ( refer to the attached pics). compass_macro2.psw Compass_PMCR_WORKING.cxp
  11. Unable to Recieve data from RS485 in protocol macros

    hi Dan ,  "The Modbus Function Code 06 is normally a "write single 16 bit register", so you'd have to write each register value one at a time with separate 'transactions'.  "  How can i write it in each registers ? Should i write my protocol  as " <a>+[0306]+&(W(1),2)+&(W(1+2),2)+&(W(1+4),2)+W(1+6),2 ' , which is (01 03 06 XXXX YYYY ZZZZ CRC)
  12. Unable to Recieve data from RS485 in protocol macros

    Hi dan,    Thanks a lot. Let me try again!!
  13. Unable to Recieve data from RS485 in protocol macros

    hi Dan & team,   So can I use MODBUS-RTU for SCU and General purpose device communication ?  Does it work if i follow the following ways? connect device to SCU Change SCU setting (MODBUS, baudrate , parity, etc). Use CMND instruction  in ladder. Thanks in advance.