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Registered: 1442612739 Posts: 132
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Rusty of the ones I dealt with the IMI that John mentioned was my first choice.
Registered: 1442538912 Posts: 1,810
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"No matter what they're telling you, they're not telling you everything." Always remember that. In this instance, I found out they were asking about the switches because the power for all the electronic switches was fed from a single breaker. The breaker tripped, and shut down a whole bank of fans (4 or 5). The switches may or may not be in good working order - as far as I know they've never been checked, and as I've asked before, how do you actually test them? I have a way, but it wouldn't be all that simple.
We actually have real-time vibration monitoring on the bearings, with alarm and trip limits set up. They work ok except for the annoyance of faulting to 1 in/sec (and tripping out) if there is a break in a cable, which is sometimes a problem (don't get me started as to how the cables get broken). Just recently on a fairly large, overhung fan with roller bearings, I get a call that "we lost a bearing." Checking my data, I didn't see anything particularly worrisome the last survey. (Always makes me nervous, even when they don't seem to be pointing a finger at me) We'd had trouble for some time on this fan with one of the sensors showing 1 in/sec all the time (broken cable), but they couldn't find it and hadn't replaced the cable. I figured they'd just disabled the trips, and the bearing failed with no alarm. When I finally go over there last week, I find out they didn't just lose the bearing. If caught on fire, came apart, the wheel was damaged. It was all removed and sent out so I didn't see any of it. But then someone said it looked like something had "gotten into" the wheel. Later, I heard from someone else that the fan kept tripping (apparently the trips were active), so -- you guessed it -- they raised the limit so they could keep it running. I am really pushing for remote monitoring so that I can at least know what actually happens on these fans. I believe there is a lot that I never hear about. __________________ "The trend is your friend"