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  1. M

    Operator Height Adjustment for Heavy Machines

    I'm looking for a way to adjust the operator working height on a machine - but an ordinary small hydraulic lift system will not be sufficient. The machine in question weighs approximately 3500 lbs. I've looked around for commercial solutions to this problem, but to no avail. Most height...
  2. M

    Dealing with Automation Knowledge Loss

    How do "good" companies deal with employee turnover in an extremely skilled position, such as controls engineer/process engineer/chief technician/etc. When I left my last job, I spent my last month there teaching people everything I could think of. I showed how to connect to all the PLCs, what...
  3. M

    Motor failure - terminal block burned off motor - why?

    The situation : 7.5hp motor, running fine since startup. 480V, 3 phase, has fuses and contactor with overloads upstream. Overloads were set to 2A under motor FLA, with manual reset. Today, operator stationed near said motor said it sounded funny. Checked fuses, one leg blown. Check resistance...
  4. M

    How to deal with unresponsive vendors/salespeople?

    I am an engineer, but my day to day job description basically is keeping the machines running at a facility. Unfortunately, a lot of this means working with outside machine builders/parts suppliers/etc and some of the time, it goes very sour. Let me give one example. We have a piece of...
  5. M

    Cycling heaters before the days of SSRs

    We have a piece of equipment which is almost new but has contactors connected to a process controller to control heaters in the 2-5kW range. This is incredibly frustrating, as we have barely made it a year of operation and now have to replace the contactors. How in the heck was it done back in...
  6. M

    HVAC Fractional HP Fan motors- Why are most of them junk, and how to get better ones?

    Back when I was working in maintenance, I always wondered why every small (1/20 to 1/3 hp) blower motor/condenser fan was a complete pile of garbage. It seems like any machine we've purchased with one of these, it's ended up failing within about a year and a few months time - I guess they really...
  7. M

    Safety Relays & Contacts in Series

    I'm always trying to improve my knowledge on one topic or another. Lately, I've been reading a bunch about safety relays. My question is this - if you have one circuit that has the same purpose ("E-stop!") .. can the contacts be in series with one another? Note - this is not a question...
  8. M

    Lowest cost option for multiple velocities for hydraulic cylinder?

    The machine being controlled has a hydraulic cylinder which is moving a ram up and down, basically a hydraulic press. Not a very big cylinder, 2.5" diameter rod, 4" dia piston , and 20" of stroke (These figures are not absolute - just a rough estimation off the top of my head) Right now, it has...
  9. M

    Somewhat OT - Why do conveyors cost so much?

    I'm shopping for conveyors right now for a few different projects, and as I'm doing this, I am constantly blown away by how much conveyors cost. Seeing as the majority of my job has been spec'ing components, I'm always curious about the economics of things. It seems like that since most new...
  10. M

    How do you ensure you get truly reliable equipment?

    I work for a small company that buys a fair amount of semi-automated, custom equipment per year. We have a tremendous amount of problems with getting reliable equipment. It seems like everything we get in - "turn-key", we end up having major downtime, multiple days of downtime every 3-4 months...
  11. M

    Outside Repair Services Hourly Rate - (Not machine shop)

    Can someone explain this to me? I have used all sorts of outside contractors in my maintenance role. Everything from AC repair, roof repair, crane repair, etc. What all of these companies have in common would be absolutely insane hourly rates compared to what most people talk about on this...
  12. M

    Can Dry-Type Transformers be Repaired?

    Does anyone know if smaller transformers are ever repaired, and what kind of places would do them? At my workplace, we have a 480V to 380V, 15 KVA general purpose transformer that has had one set of windings get really hot. It is very likely some turns are shorted. I realize it may be more...
  13. M

    Looking for a durable shim stock punch set

    At my workplace, the tool room makes quite a few shims on a daily basis. These shims will typically made from .010-.030 thick steel shim stock, and will have at least a dozen holes in them. Right now we use something like this. McMaster-Carr It's a clear acrylic block with through holes for...
  14. M

    Servo Motor Constantly Faulting- From Feedback?

    I have a machine with a back-and-forth axis that consists of a servomotor directly coupled to a ballscrew, approximately 2kw. This is driven by an older Allen Bradley 1394 system(SERCOS) and controlled with a Controllogix. The problem stared by the motor "oscillating". In one particular...
  15. M

    Engineering/Project Estimation for Internal Projects

    This topic could also be in the owner forum, but I think it might be more applicable here. In day to day business, I'm often asked to estimate the cost of internal projects. Some are straight forward, like machine repairs, which is basically just (cost of material) + (man-hours * hourly rate)...
  16. M

    Is automation typically an in-house or external function for most manufacturers?

    Just curiosity. My employer outsources the majority of automation/machine building projects, but I understand there are a lot more out there that do most of the stuff themselves. It seems like alot of automation integrators(builders?) in my area got their start by doing "in house" automation ...
  17. M

    OT: Do companies honor warranties in the industrial world?

    I've been working in maintenance for a little over two years now. In my two years, I have seen absolutely nothing that would make me think that companies that supply anything to ours... be it service in the form of repairs, or parts.. will honor any kind of warranty. I have lost count of the...
  18. M

    Good stand/arm for dual monitors?

    This is not necessarily a CAD/CAM question, but I understand many people in this sub-forum use dual monitors. What is a good "arm" that would be capable of holding 2 22" LCD monitors? I want to use them in a horizontal configuration. I am afraid the "cheap" ones aren't rigid enough for me to be...
  19. M

    The "PLC Lab"

    At my workplace, the former maintenance manager put some spare components together to make a PLC/automation prototyping lab in one of our empty offices. It's simply a few switches, PLCs, HMI, relays and terminal blocks to prototype anything or provide an easy place to troubleshoot components...
  20. M

    Properly Sizing MOVs for Inductive Loads?

    At my workplace, there are a few machines with solenoids directly connected to relay outputs on PLCs. This doesn't seem like it would be an issue, but some of these PLCs are having outputs fail with not that many cycles. These machines came from the manufacturer that way. These outputs in...

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