OK. Anyone with knowledge of your typical 3 phase motors knows reversing any two phases causes them to rotate in the opposite direction.(Well, since it's past a week . . .) Could it be ABC (or equal) = up, ACB (or equal) = down?
Nothing wrong with that but what's the paramount reason why it matters, c'mon lads n' lasses, you can parse this??So that after plugging it in, somebody marks the "UP" and "DOWN" buttons properly? And then makes sure to check it every time it's reconnected?
Calling @dvsDave and / or @egilson1 and / or @What Rigger? [B] @derekleffew [/B] [B] @RonaldBeal [/B] and /or @ all other REAL riggers; I suspect we have a WINNER personally, I'dve settled for the chain hoists would've ignored their limits, the limits you were counting / depending upon for too, too, many reasons and would be more than STARTLED when the hoist, or all the hoists in your rig, were missing their limits when they'd been operating FLAWLESSLY during your out only a few sleep deprived hours earlier.My suspicion would be the limit switches. If you hit the upper limit you want the hoist to disable going up but still want to be able to go down.
If the phase rotation is backwards so that up is down and down is up then those limit switches won't engage and stop the travel, but it would stop you when you try to come back down?
My suspicion would be the limit switches. If you hit the upper limit you want the hoist to disable going up but still want to be able to go down.
If the phase rotation is backwards so that up is down and down is up then those limit switches won't engage and stop the travel, but it would stop you when you try to come back down?
@JonCarter I'll try and explain it, others will likely post wile I'm doing my slow-typing best. I'll attempt to oversimplify and use a more familiar electric garage door opener for illustration purposes, the same situation applies to (within) electric chain hoists.OK, guys, educate me. Don't "limit switches" activate and disconnect the motor when specific physical events occur? E.g., when either end of the chain reaches the point where it's about to run out of the mechanism? Why does the direction of motion when the event occurs matter whether it's going up or down?
@DrewE Excerpted from my Post #15: "The upper EOT intentionally DOES NOT inhibit all power, if it did you wouldn't be able to close the door "What Ron says is true (well, at least to the extent of my knowledge).
Just to be perfectly clear, the basic reason why the limit switches do not interrupt both controls is that you'd still like to be able to move the hoist or door or whatever in the opposite direction of travel once you've reached maximum travel in a given direction. Once the door is all the way open, it's handy to be able to close it under power control; but if the limit switch affected both direction controls, you could only move it manually (until clear of the limit switch). It's rather obvious once you think it through all the way, but not necessarily before then.
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