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  1. guilio2010

    Edge Computing and examples

    I am having trouble really defining what “Edge Computing” really means and how it will improve my process. Example: If I have a controller at a remote location monitoring a pressure from a transmitter and based on a condition, it will shut off a motor and Alarm, how does edge computing on a...
  2. guilio2010

    High Voltage lines near transmitters

    We have grounding all over our equipment, bonding, and then we take it back to earth ground bed. For our transmitters, we have a specific isolated ground that all shields connect to and then that will tie into our ground bed. Even with the ground, I see the 60Hz wave with the scope. What’s the...
  3. guilio2010

    High Voltage lines near transmitters

    itsmoked, I remember talking to the power company before during the construction of the location and I don’t remember the exact voltage (or find my notes) but i remember them mention a value above 300kV. 345kV sticks in my mind but I don’t know the voltage ranges so I could be wrong. These are...
  4. guilio2010

    High Voltage lines near transmitters

    Thanks Cuky2000. We have shielding around our conductors but measuring the shield noise at our isolation ground, I read nothing. I would expect that if I was getting that much interference, similar to what I was getting with our VFDs, I would see this. I’ll have to check our other components...
  5. guilio2010

    High Voltage lines near transmitters

    No. We just commissioned the site and started at day 1 and would randomly clear but would stay HIGH level for most of the time. I increased our polling rate to see clear and alarm times and how often. Historically if we had issues like this it was from our VFDs causing spikes in the signal and...
  6. guilio2010

    High Voltage lines near transmitters

    That’s again wayne440. I see you edited your post. Transmitter is a guided wave radar. Communicating RS485. The transmitter is mounted to a metal tank 30’ in higher. We current run 20/4 wire, shielded. 2 wires for power, 2 for communication. This is the end device in a daisy chain wiring...
  7. guilio2010

    High Voltage lines near transmitters

    Thanks wayne440. I agree on many devices operate fine near these lines which is why I am not saying it’s root cause but when static discharge is reported I have to consider it a source to investigate. As for need more detail, that’s where I have to reply back with what details do you need in...
  8. guilio2010

    High Voltage lines near transmitters

    So I’ll start with a basic question. If I had a transmitter near a HV power line (say 50’), is it possible that the power line could induce a voltage on the transmitter or power/comms wiring and cause false values? If I took a scope and noticed that the voltage readings increased as I walked...
  9. guilio2010

    What connection (delta wye) would be best

    I have conflicting opinions on this project. We are looking to need 3 phase 480v service mostly for process heating (225kW). We have other items such as lights, heat tracing, etc...which has me thinking Wye (multiple voltage requirements). Another individual in the this project said they want...
  10. guilio2010

    API (Application program interface) - ROC800

    I have been wanting to make a user program for the ROC800/Fischer (Emerson) products. I searched and asked around but can't find anything in regards to the API that is used for developing the user program. Does anyone know of where to get the software or if there are multiple software...
  11. guilio2010

    Self Exciting Alternators

    I want to confirm my thought process on the alternators we use. We have various engines with a 12180-SEN alternators. This alternator from my research is self exciting so we would just connect the battery positive to the Batt terminal post. From here, the alternator will adjust the charging...
  12. guilio2010

    MODBUS maximum wire length

    From my end, the specs states -7 TO +12. I see the TO as it can vary the output of the driver between these values and so long as your difference in voltage is 200mV to the receiver, then it detects the HIGH or LOW. I'm wondering what controls that output if it's +12 or -7 or +1, etc...is what...
  13. guilio2010

    MODBUS maximum wire length

    Thanks all. I'll start recognizing some stars. Irstuff. Thanks for the document. I actually found in the datarate vs cable length that explained a question about can I go further distant then with slower data rate. I reworked out your example with 9600 bps and came up with 9800' but from the...
  14. guilio2010

    MODBUS maximum wire length

    Based on itsmoked, so long the larger diameter cable has the same thickness insulation and dielectric as the smaller diameter cable, then it will experience more capacitance. Else, if they are separated further, then capacitance could be decreased. I totally agree that smaller cable for...
  15. guilio2010

    Remotely programming PLCs.

    We have a similar setup where we have multiple controllers in remote locations. We are always changing set points, updating logic, firmware, etc... If your controllers are part of a safety system, I would be leery of changes programming remotely and not on location. I tried this once and when...
  16. guilio2010

    MODBUS maximum wire length

    I think in summary of this, one action item I will go is specifying the wire to match the device rather than trying for a one size fits all. We have a standard, stick with the standard. Realistically, we have all low powered devices and the only device I see that doesn't meet our standard is a...
  17. guilio2010

    MODBUS maximum wire length

    Thanks all. I wish I didn't have to put this much work into something like this but this is what is needed to make a change. For the wire, we generally run the same wire for all the devices. One pull can contain 12 to 20 of the same wires that will land on the 485 device but also provide...
  18. guilio2010

    MODBUS maximum wire length

    I don't think we are at the point in distance of needing fiber optics. From readings and what I have calculated in distances, we are at about 2000' with 12 devices connected. Our baud rate is 9600. Due to he layout, we run up to the device, back to a central marshaling cabinet, then back out...
  19. guilio2010

    MODBUS maximum wire length

    I'm going through calculations for various equipment and the one item I haven't found much information on was calculation the maximum distance for MODBUS communication based on wire size. I seen general rule of thumbs and basic equations in regards to data rate and distance, but I would think...
  20. guilio2010

    Lightning Strikes and design theory

    Thanks for you time all. I know lightning strikes are very hard to distinguish, but from my end, I get a lot of force that people want to jump to this conclusion because it's the easiest to understand, and not really look into it to see if that is what really happened. Power0020: Thanks for...

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