gravitar

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Everything posted by gravitar

  1. As I was doing an HMI cutout yesterday, kicking up profuse grit and spark with my die grinder and seeming to take forever, it dawned on me that perhaps there's a better way. So what better place to ask.. how do YOU make your cutouts? I've never seen it done with anything other than a die grinder/cutoff wheel, but then again I've never worked closely with a large OEM that has to cut out dozens of panels a day. If I were the foreman of a shop like that, I'd be looking for a quicker, cleaner way!
  2. Just curious.. Does anyone else here work with resistance welding controls?
  3. I just got an auction listing for a company that was using "Anthropomorphic" welding robots. I wasn't familiar with that term so I googled it, and I guess it means "possessing human qualities".. Which doesn't really tell me anything :) Applied to the context of robotics, what does this indicate? Just catchy advertising jargon written by someone that doesn't know robotics?
  4. Just curious... I saw one for the first time a few months ago on a robot cell.. And wouldn't you know it, I've been called in on very short notice to work on that very workcell now!
  5. I've got a question for those of you that are well-versed with US electrical regulations. The place I work for set up a piece of equipment as a standalone workcell, that was removed from a larger system. There are three electrical panels for controls, as well as a couple robot controllers and another small enclosure that is attached to a packaged piece of machinery. My question is about the three control panels. None of them have any sort of disconnecting means on the outside, but have manual rotary switches in them. Two of them are fed by a bussdrop cable that goes overhead and drops down about 100' away at a load center near another piece of machinery. The third panel is fed from one of the two mains-fed panels. So here's my question.. Is there any requirement about how close the disconnect switch must be to the supplied panels(s)? Does the voltage of the circuit affect this? One of them may only be 120VAC, but I'm sure the other one is 460 3ph. Is it acceptable for there to just be a placard showing a map of the floor that says "Lock it out over THERE"?
  6. Purpose of set-retentive coils?

    Help me out with this, guys.. I'm familiar with the concept of set/reset coils. It's the same as latch/unlatch in an A-B PLC, it seems. But this whole "M" coil thing.. give me an example that I can grasp of what this would be used for! Especially SM/RM coils.. What is the benefit of adding retentiveness to a set output? This program I'm dealing with is full of SM/SR's.
  7. Transfer my activation

    Yeah.. but.. Haven't we officially come to The End Of The Road, for EVRSI activation? Aren't they finally living up to the threat they've been issuing for the last several years, and the latest versions finally are not recognizing EVRSI?
  8. Extreme Newbie Proficy ME Question

    Hello! I'm currently working on my first experience with a GE PLC. It is a small automated shear table with a Series 90-30 CPU374 PLC. The program is already written, I'm just trying to make a few small improvements. Here's the first thing I'm trying to figure out.. I hoped that I could put a contact between a timer and its output coil, but Proficy didn't like that. So I'm figuring that I need to add a rung, assign a new bit to the timer done bit, and use this new bit with the condition I want to trigger the bit that's currently the timer done bit. Here's my problem.. I'm looking in the %M table, and it shows me a table of bits from 0-4096. I can see their present state, but I can't figure out how to see a "usage" table. How do I figure out which bits are unused in the program so that I can use one of them?
  9. Extreme Newbie Proficy ME Question

    Does the "+" coil/contact signify more than just allowing a rung to be longer than the width of the display? I had plenty of room on the displayed rung to insert a contact between the timer block and the done bit, but it seemed that proficy would not accept that as a valid sequence of instructions.
  10. Vibration Monitoring

    That is awesome. Make sure it has a green "Calibrated" sticker on the side of the glass :)
  11. If reliability is the main consideration, you're right to consider a PLC over a PC-based solution. Here's something else to consider.. Will you be able to program this with your employer's software, or will you have to buy your own? PLC software varies in price from several hundred to several thousand dollars. If you're only planning on making one (or a few) of these devices, you're probably going to want to limit your choices to the PLC families that use the least expensive software, or better yet ones that can be programmed with software you already have access to.
  12. I wonder if a PC running a small VB app driving a discrete I/O module, might be the most cost-effective solution.
  13. WORKMASTER INDUSTRIAL COMPUTER

    Of all the things to call one's self.. poopstain?
  14. Panasonic Toughbooks

    I feel compelled to comment because I'm a toughbook user.. no, make that a toughbook enthusiast. First of all, Panasonic has several product lines that all share the "Toughbook" name. Personally I think that's a bad strategy. The only ones that deserve to be called Toughbooks are their "fully rugged" line.. The CF25, CF27, CF28, CF29, and the current model, the CF30. All the other ones probably have some degree of ruggedness, but probably not what would you would expect. I only deal with the fully rugged ones and have no desire to try any of the others. Ok with that said, everything Paulengr has said is true about the "fully rugged" line. They're comparitively slow, heavy, expensive, and the screens are lousy. If those are your performance metrics, then don't buy a toughbook. They aren't for everyone.. Heck I would go so far as to say that they aren't for ANYONE, other than those very few people that put reliability, impact resistance, weather resistance, and the couple of other features that toughbooks have (touchscreen, backlit keyboard, vehicle mounting, etc) above all else. I'm in that tiny minority. I think they're ideal for field service applications, or anywhere else that you REALLY, REALLY need that slow CPU and lousy screen to keep working, no matter what.
  15. I've just started working for a company that employs a WIDE variety of PLCs. Some machines have AB, some Siemens, some Mitsubishi, some PLC Direct, some GE, even some brands I've never heard of, like Control Technologies Inc. Likewise, they have HMIs of just about every conceivable flavor. Some of the larger lines mix-n-match several brands.. One line I was working on has a Control Technologies PLC (w/ TCP Quickpanels) controling one thing, a SLC 500/Panelview controlling something else, a PLC Direct (C-more HMI) controlling yet another part of the machine, and a Mitsubishi controller with a Maple Systems HMI controlling yet another part of it (!!) Naturally I inquired into the reasoning behind this. One maintenance guy that had been with the company a long time, explained that in the beginning it was just one PLC, but every time they added functionality, they added another controller and it would always end up being vendors-choice or whatever seemed to be cheapest at the time. I then asked my boss, my boss's boss, and a fellow controls guy about this crazy situation. The answer I got from all of them was along the lines of "Logic is Logic", "They all do essentially the same thing", "You program one you've programmed them all", "Yeah, its a challenge, but I like challenges", etc. Now, to me this whole situation seems asinine. They think it's a badge of honor to try to cope with a PLC version of the "United Nations", but I'm not convinced. Am I just being lazy/ignorant or have I walked onto the set of the Twilight Zone?
  16. Thanks for the tip! I did somehow convince management to provide me with the latest rev, so that hurdle is crossed. It looks like even with this newer version though, it is trying to find help files from an external server.. Very inconvenient!
  17. Timing Diagram for PLC Programme

    My guess is the background image is there to convince you to buy the product.. If it works well for you and isn't insanely expensive (most shareware isn't), your best bet is probably to buy the full version!
  18. RSview ME & Vista

    Haven't we reached the point where OEMs can't sell new computers with an XP COA on them anymore? It would be pretty silly if A-B couldn't sell an industrial PC capable of running their own software!
  19. Wouldn't it be nice...

    I asked about that when they first came out.. was told that online editing takes a lot of "horsepower" and they couldn't fit it in to the 1500's processor slot.. I'm not sure I believe that though.. My guess is it was a turf war with the SLC 500 team :)
  20. I just spent a good long while this morning trying to do just that. I might be approaching this from the wrong mindset, but I just didn't see how you could walk up to an "unknown" processor and capture the program! Anyone know how to do this? I'm using Cimplicity Machine Edition v. 5.0. Just to add insult to injury, the online help system in this particular installation doesn't work, either. It seems to want to go to the web to find the help files, but I'm having no luck getting it to penetrate the company's firewall, nor can I seem to be able to reconfigure it to use local help files.
  21. Robot Forum

    I see some here and some in the GE forum. I think that if you add it, they will come :) I wonder if there has been enough of an increase in active membership here that it might work now even though it failed in the past?
  22. Robot Forum

    +1
  23. I think you hit the nail on the head with this one.. My first "venture into the unknown" is with a GE 90-30 PLC that has been programmed by a contractor that used reasonably current software.. They just handed me a laptop with 4-year-old software on it and, big surprise, it won't open his project!
  24. Makes me wonder if they've moved their headquarters from Milwaukee to Beijing :)
  25. Wouldn't it be nice...

    Not sure why we're doing it-would-have-been-nice's, because none of this is ever going to happen, but.. it would have been nice if they made the CLX chassis downward-compatible with SLC 500 cards, like it was supposedly originally designed to be.