slcman

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About slcman

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  1. micrologix 1200 C series Modbus configs

    1761-NET-AIC+ is not a protocol converter, it's just a RS232 to RS485 converter. To use Modbus you need to change comms driver in Channel configuration (see picture). However, since you only have 1 port, you'll need get DF1 comm to monitor/upload/download. To do that press and hold special hidden comm button for 1 sec (picture), then port protocol will return to default. Once programming job is done, use the same button or laptop to return to modus comms.
  2. How to scroll faults in ML1400 and PV800?

    You should consider to use the alarms feature in the hmi. Alarms does exactly what you want to do. Multistate indicator are not design to show alarms. This is relatively simple to use, clic on alarms in factory talk (left tree). Then select tag who contain your error message. To keep it simple, you should assign on bit per alarms. Next, on message tab you enter the text you want to display while the bit is set. Once done, you have to create a page to display alarms or use the default [alarms] screen.  this is the global idea, just ask if you need more detail. regards
  3. Change P in running PID

    Sorry if my answer was rought a little, very often I got answer from people who doesn't know what they are talking about. They just answer without answer, it's look like it's not your case Wow thanks for reply. I do programming since 25 years, however I do not pretend to be an expert on pid subject. My experience is more related in manufacturing not process. I've really ask Rockwell on how to change P while loop running and they recommend to put loop in manual. This is strange, I already change loop parameter on the fly with Schneider M258 and Siemens plc. Maybe it's wrong to put it in manual..honestly this is a good new and it make sense. I'm not always impress by AB tech connect. You're right about the trend, it's look like a classroom environement. I made it with Studio 5000 emulator v30 for testing and try to figure out what to do before the visit to customer. I'm sure you understand this, production environnement is not a good lab. I'm actually try to figure out how to fix this loop. Altough emulator is not real life, it help to test the idea. You're right again about the very small value of I. The loop have to respond very fast. It drive a 125Hp fan and the load is very variable. PV is pressure. Now let's talk about real life, real trend.  PLC: 1769-L33ER v30 Instruction is PID (not PIDE), it run in a periodic task at 75ms.   Fan is used as exhaust from combustion from boiler. At any time a boiler should start and create hudge change while purging. The idea was to use an higher P while purging. But if you have better sugestion GO I like to learn. This is a trend at normal operation, you can see variation from press transmitter. They will always have some variation on press because of combustion. We ran few test without any boiler in run and pressure signal is quite linear, combustion create fluctuation, we have to deal with. This is why I use an average value. light blue is instant reading from pressure transmitter blue is average value I calculated and use for pid, hmi and so on red is PID.ERR tag brown is speed command 0-100%  green speed feedback 0-100% dashed white is setpoint *pay attention, pen are not on the same Y scale   Thanks again for your time, this kind of forum is very usefull for people like us, I'm member since 2005, each time I got an answer I try to answer about 10 questions to keep to forum alive.   regards
  4. Change P in running PID

    We don't care about I & D, my question is "I need to change P while pid is in run". I can't change P direct in the tag LOOK THE TREND! Rockwell also says it's not a good idea. plc: 1769-L33ER any suggestion?
  5. indirect access to hardware inputs

    As far I can see, you may get the input inderctly but not the slot number. I haven't try with real plc but the following code didn't prompt any error. Wish it help  
  6. Change P in running PID

    Hi all, I need to change the gain in a PID instruction while pid is running. I can't just write new gain in KP variable (it will be too easy), it make a hudge bump in CV..not really what we need (see picture). Rockwell suggest to put pid in manual (.SWM) then change the gain and put back to auto. It's work but not fast enought, it's look like pid take time to calculated few thing on manual to auto transition. I'm sure there's a way to do this, I can't be the first who need to do that. Thanks for help  
  7. Dynamic String Size

    I used Cognex bar code reader with AB. I copy the bar code string in a string tag by using the .ResultLength variable (see picture). As you can see in the screen shot .LEN or ResultLength does not include null. regards
  8. Simatic HMI

    You have to set limit in tag. As exemple, in Portal, go to HMI tags folder, then select a tag, goto properties --> range. You can set a constant or tag as limit. Numeric entry doesn't have limit, tag does.
  9. please guide me how to import tags from rsview32 to rslogix 5000 as an input for softlogix controller

  10. S7-1200 PID compact min process value

    Thanks Ross I really appreciate your help. I didn't see Substitute output value field because my plc firmware is v3.0 and that firmware cannot use PID v2. I'll upgrade firmware and try with PID v2. regards
  11. S7-1200 PID compact min process value

    first thanks for answer. Could you please tell me where you enter "Reaction to error - Substitute output value". regards
  12. PID S7-1200 can't enable.

    Clic on upper right icon (see picture). You need to start the pid controller >(picture Start PID). For have the pid compact start at powerup check enable last mode (picture start at power up) You can detect pid controller mode in your program and change it. I usually use manual config and force run auto or manual, this way I never get a stopped pid controller. (picture mode detect)
  13. PLC and HMI access remotely

    I agree with Nova5 VPN is is definitely the best solution. However, I strongly suggest eWon VPN router. It have a built-in serial/ethernet or PROFIBus/ethernet Gateway usefull for Siemens 2DP plc. IT doesn't need to be involve in the vpn, eWon use outgoing connection - see video on eWon web site. I have about 20 eWon in Canada/US all work fine, device is really easy to use. http://www.ewon.biz/en/home.html
  14. Hi, I use PID_Compact instruction to control a MM440 drive speed. I would like to set a min output value of this instruction as I can do with S7-300 serie. Please don't tell me I can use min drive speed...I know that! I want to have a min speed set in pid instruction. Pid config screen seems the place to do that but when I enter a value greater than 0 in Advanced settings -> Output value limits, I got a red X and portal says Enter a value between -100.0 and 0.0 I can't beleive we can't do that simple thing! Any idea? The only workaround I've found is to write my min speed to my output tag if it is less than min speed. It works but PID take a long time to react when it increase the speed from 0. i.e. output tag is set at 50%(min speed) nothing is changed while pid increase speed from 0 to 50%.
  15. I need to track our control panel (gps or something similar). Any advise, part, manufacturer? I do have internet in the cabinet. thanks