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  1. JohnWaa

    Exploding MV motor weatherheads?

    It sounds to me like it was a magnetic pulse that took out your weatherhead. The old "opposites attract" and "likes oppose" can really put a hurting on anything nearby. :) Ever see a welding cables slap together? Or hear wires "ringing" in a conduit during a dead short? The magnetic pulse...
  2. JohnWaa

    best way to convert 400 VAC environmental chamber to 480 VAC

    It should. You would just have to purchase a bigger one. Although, I don't know how a VFD would respond to driving an oven...
  3. JohnWaa

    EXP or pipe.

    Either way you are going to have losses, but with electricity you can't easily add sections of cable (ever make up an armored cable? It's a bear). As much as I hate hydraulics, I would say that in this case it's the easier of the two options.
  4. JohnWaa

    meggaring cable

    I would say so, is there any reason why you would suspect otherwise? Are you getting ground faults?
  5. JohnWaa

    [Topic] A little help in programing or same ideas whould be useful

    Well, what I gave you was a FIFO. :) But not one in Step 5... Try www.plcs.net, there might be someone there who could help out.
  6. JohnWaa

    Need VB.Net Help - Trying to Publish for Older Computers

    You can still get Visual Basic Express 2008 here/; http://www.microsoft.com/express/downloads/
  7. JohnWaa

    PLC for use on a house? How could you use it?

    I bought one for a project at work, it was extremely cheap (as PLCs go) and it was a cinch to program. I downloaded the *free* programming software and had my program written in just a few hours. It was simple. :) The software is great, I'd say it's better than anything from Rockwell. Or GE, or...
  8. JohnWaa

    C50h "Data rack error"

    Could be. Put a scope on it and see what kind of noise you are getting back from your IR sensors. Here's what the manual has to say about it: Probable cause: "Either noise, lightning, improper grounding, lack of surge suppression on outputs with inductive loads, or poor power source." So...
  9. JohnWaa

    RSLogix 5000 FIFO

    Here ya go. :) I exported it to a L5K file (open it in RS5k and save it as FIFO Example or whatever). I didn't pick any particular processor, or I/O, etc. But you shouldn't have any trouble editing it...
  10. JohnWaa

    RSLogix 5000 FIFO

    In the spirit of OOP (particularly the "code reuseability" part), I'm going to recycle some puesdo-code I wrote earlier tonight for your problem. For our example let's create five tags (DINTS would be fine). call them Reg1, Reg2, Reg3, Reg4, and Reg5. Do this for each of your four pumps: If...
  11. JohnWaa

    [Topic] A little help in programing or same ideas whould be useful

    I don't have any experience with a S5, so how about some puesdo-code? Pick an area of registers that are available to you, for our example we'll pick ten of them. And for our example we'll say that they are registers 1 - 10. This arbitrary limit of ten registers assumes that you would never be...
  12. JohnWaa

    Crash course in PLC Hardware required for smart devices

    Well, like I said in my previous post, I haven't tried it as of yet (I'm still in Kentucky). And like I also said in my previous post, I wouldn't ever seriously implement it. But for curiosity's sake, I'm going to run a test just to see what it does. Why not? I'm entitled to a few "stupid...
  13. JohnWaa

    Reduced voltage starter

    It's DC, I don't see why not... Well, if you get it from a company like Milwaukee Resistor, then they will be able to point you in the right direction. But basically you will have to fuse it and enclose it inside a case or behind a plexiglass cover to keep it out of way of wandering fingers...
  14. JohnWaa

    DC Motor Test Help

    Back in the 80's LoveJoy (the coupling people) branched off into the drive business. For testing and burning in their drives, they used two AC motors, one 1800 RPM and the other 1200 RPM coupled together to provide a load for the AC drive (the drive was connected to the 1800 RPM motor). This...
  15. JohnWaa

    Century Repulsion Start-Induction Motor Help

    Have you tried contacting A. O. Smith for service parts?
  16. JohnWaa

    Reduced voltage starter

    Yeah, I didn't think so. I think these guys might also deal in AC reduced voltage starters. Look on their projects page (they advertise that they refurbish old starters). It doesn't hurt to ask. http://www.dccontactors.com/index.html These guys might be able to build you something...
  17. JohnWaa

    250 Hp motor running 225 amp + 152 Kw @ 60Hz. 50 Hz Operation?

    You probably can get an external cooling fan kit for your motor. If not, mount a large muffin fan to the rear of the motor (I've done this in the past and it works very well). As for the loading of the motor, check with an applications engineer at the pump company. They should be able to tell...
  18. JohnWaa

    Reduced voltage starter

    Autotransformer style won't do? AB still sells these.
  19. JohnWaa

    Basic wiring in series query

    It looks like R7 isn't being used. And you can program it to provide that signal that you want? Great! Making some general assumptions here (that the yeast batching equipment that you are connecting to is off of the same control system). Yes, you could take a wire from terminal #55 (actually...
  20. JohnWaa

    PLC backplane protocols

    And not that reliable in my experience. Junk, basically. Well, just glancing at a few datasheets, I see that some of them have DMA access... But you're a motion-guy, and that means high speed. I work in the world of "same day service", so things are a bit more relaxed for me. :) But with the...

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