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I am assuming you are using an NA series HMI. To the best of my knowledge, you can't include a variable in the Message or Details fields of the NA series alarms. What you can do is go to the properties of the alarm, and it gives you a spot for "Additional Information". This can be a variable value (Boolean, Numeric or String), but shows as a separate column in the alarm viewer. What I have done in the past is just used a generic message in the Message column (ie. Motor Fault - Check this and that), and then used a string variable (max string length is 32) in additional information to indicate what the actual equipment was (ie. Conveyor 1). The column can be added, rearranged and renamed in the column settings of the alarm viewer object. -
I am trying to display an Error String from a Festo FB being used in my Omron PLC to an Alarm Message or General Message Display....cannot figure out how to show a message with an Embedded Variable? -
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Providing they can get away with the DOL starting of the pumps (or maybe use soft starters), this is a good idea. Only downside would be if the VSD ever failed, there would be no redundancy with the other 2 pumps to regulate pressure (ie. they are either 0% or 100%). Putting 2 pumps on VSD's would alleviate that, but if that level of redundancy was required it would probably just be easier to run all 3 on VSD's 🙂.
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Yes,its Serial Communication Unit -
My Suggestion for revision: When the auto cycle starts, Pump 1 runs on vfd power and try to maintain the set pressure using PID. -If the pressure does not reach the set value in desired time, then contactor K3 will be turned on instantly. So the pump 2 will be now work on full speed mode. -Pump 1 still on VFD will try to maintain the set pressure using PID. --If the pressure does not reach the set value in desired time, then contactor K5 will be turned on instantly. So the pump2 and pump3 will be now work on full speed mode. -Now Pump 1 still on VFD will try to maintain the set pressure using PID. If the pressure increases then the set point and VFD runs on Low (20hz) speed for set time, the reverse sequence will work. - If pressure remain high for some time and VFD at Low (20hz) speed then, contactor K5 will be off. So pump 3 will stop and pump 1 will run on VFD with Pump 2 to maintain pressure. - If pressure remain high for some time and VFD at Low (20hz) speed then, contactor K3 will be off. So pump 3 and pump 2 will stop and pump 1 will run on VFD to maintain pressure. This avoids the dangers of bypass contactors and the fact that most VFD do not like their output interrupted. -
By Jefferson Ryan · Posted
I was very interested in this and I had to figure it out myself. For the record, these are working ASCII examples of 3E frame: Set M69 to 1: 500000FF03FF000019000214010001M*00006900011 the CPU is going to answer D00000FF03FF0000040000 Set M69 to 0: 500000FF03FF000019000214010001M*00006900010 again, the answer will be: D00000FF03FF0000040000 Just use any TCP enabled client capable to send ASCII strings. In my test, CRLF line endings were ignored. Tested on a Q03UDECPU The 3E frame works with all Q03UDECPU. It´s the simpler 1E frame that was implemented later, so units with an old firmware are incompatible. Tips: 1) After configuring the network parameters, you must reboot the CPU. Same after changing between ASCII and Binary. 2) You must be able to "Telnet" to the CPU on the chosen port. If you are unable to, you have a connectivity problem. I'm learning the 3E frame format by analyzing the source code of https://github.com/mendozaphd/Mitsubishi-MC-Protocol and comparing with the Mitsubishi docs. -
Hello, Did you solved this issue? I am looking for PanelMate Transfer to try upload new files to my HMI. Could you help me? -
I have done several parallel pumping systems for pressure maintenance and agree with the other posters about not using bypass contactors. If you want to lock pumps at 100%, it is better to use the equivalent of software manual or an output hold in the PID. I have designed a couple systems that work the way you describe in that when the running drives are maxed, they lock at 100% speed and a new pump is started to modulate and maintain pressure, but I have found that it is more efficient, and safer, to allow all pumps to modulate with a PID at all times. This helps to prevent over-pressurizing the system if demand drops suddenly. Also note that depending on the system pressure, your pumps potentially won't actually start moving liquid until they are at 50% - 70% speed, so look at your pump curves and do some testing to set the minimum speed (or feed forward) in the PID just under where your pumps actually come up to pressure.
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