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hi All Can you please help me to understand if the sine filter requires a minimum current to work properly and create sine like signal ? If yes how to determine this current as it does not seem to be listed in the data sheets. Would it make a difference if the sine filter is standard type or...

As we know control panels have low base frequencies 50/60 and 50th harmonics is only 2.5kz. All affordable spectrum analysers like rigol 815 tg have bandwidth from 9khz so does it mean they are not useful for FFT analysis of the EMC issues in the control panel? What gear do you use ? What near...

hi All Just wondering if i used good quality generic serial cable why would i not be able to connect to the Control Technique drive eg. Mentor? is there some sort of hacking required rather than studing manuals from the drive manufacturer about the pinout, protocol and speed? I feel like i might...

hi All Can you please kindly advise how to check analogue output if its working in 4-20mA mode? my idea is to connect 250 ohm resistor to the AO output, set drive to hand, disconnect motor, set ref to 100 percent and check if the voltage at full 20 mA is 5 V. Is that correct? Any other ideas...

hi Siemens does not sell power meters covering that range. PAC3220 can only do typical range 40-60hz The voltage is coming from the transformer which is stepped down by the voltage transfomer to 400V. Transformer is fed by the VFD with the sine filter so the measured voltage is sine rather than...

hi All Fundamental question so please bear with me. I understand the concept of Siemens Wincc HMI tag as a memory structure to hold many properties related to the tag so tag it is really "structure of structures" to contain all these details which is much more than just address to store the raw...

hi All Might sound ridiculous but please bear with me. I heard that apple computers can run windows virtual machines much faster that standard PCs and some people use it in automatin. I would like to verify that claim: has anybody from this forum used macbook pro (what model was it) with...

hi All Any chance somebody explains me why real numbers are not used in VFD drives speed reference etc? So instead of sending sending 90.9 percentage of speed i would have to multiple it by 10 and send 909 which is then converted by the drive itself? Why floating point arithmetic in not used in...

I feel like i am asking very wide question but it will be beneficial for many people to organise this huge chunk of automation knowledge. When answering this question can you please consider 3 scenarios: A PLC brand e-g. Siemens, Mitsubishi, Allen Bradley, Beckhoff, others B Ways to extract...

hi Do you know which PLCs support MQTT? What can be done if they dont support MQTT - would kepware with Direct Drivers be the only option for the 4.0 connectivity? Regards

Hi I am trying to structure my understanding. As i know OPC DA servers sometimes allow tag browsing but siemens does not allow this - experience with siemens sinumerik opc machineswitch on CNC. I dont think s7300 allow tag browsing as well. What about other siemens devices like 1200 plc and...

can you help me with some basics which i thought understood: 1- when server is connected to the plc but no client used is there any data being fetched from plc at all? or there must be at leat 1 client with at at leat one group and 1 item? so when client disconnects plc gets no traffic? 2- is...

Just wonder if all scada systems are OPC UA based to provide the access to the tags? In particular i would like to compare: 1 - rockwell factory talk site edition 2 - citec scada 3 - iconics 4 - intouch 6 - ignition - this is OPC UA for sure 7 - wincc How did tag servers work in the past ? was...

Hi I wonder how you would go about troubleshooting OPC DA comms between 2 computers on the same network (obviously 1 being server and the other client). The only thing know is that the ping is working between both PCs. What is the best path and the least amount of steps ? i have a feeling it...

hi all I know plc 5 inherited octal system from plc 2. But why was octal addressing used in the first place? why not decimal or hexadecimal? plc-5 internally only understands binary and other codes are for us humans… Does anybody know internals of plc 5- is it 8 bit on 8 bit bus but addressing...

hi All I have kepserverEx configured to connect to the plc but there is no physical connection there yet. Is there any way to simulate the communication as healthy so i dont get plenty of messages in the scada "Error_configuration" ? I tried to use the option "Operating Mode\Simulated" set to...

hi All I am completely green in Mitsubishi PLC (i used to program siemens) but need kepware to connect to FX3U pls with ENET adp module. Could somebody pls help me with the very basics as kepware does not talk to the FX3U yet: What software do i need to read configuration/potentially do...

hi I would like to kindly ask you about fundamental concept: In control automation can database be event driven or only polled? For example when we have scada which reads data from MES or ERP system inside mssql server can this database somehow notify scada that there is new data to be queried...

Hi All I am rather green in SAN topic which is huge (i did do some short introduction to SAN course). Lets assume you need to configure SAN (storage area network) for the history records of the SCADA. 1 What things are critical to consider when designing SAN? performance, choice of iSCSI, FC...

I would like to deepen my knowledge on modbus so please answer the questions if you can: 1 Is it true that modbus ascii is addressable the values byte by byte - same as modbus RTU. This is different to modbus TCP which is addressing the values using 2 bytes? Is my understanding correct? 2 what...