@turkey_hollow_rr posted:I'm still working out in my mind how I might implement some kind of minute adjustment for the limit switches should it prove necessary. Perhaps in addition to angle brackets there could be a bolt threaded through the bracket with a lock nut on top. The bolt head would then make contact with the switch.
Did you look at my thread? The spring loaded switch sensing the slight slack in the cable really solved my problem of unreliable lower limit switch activation. Obviously, the upper limit switch isn't all that critical, you just have to make sure you don't go past the point where you run out of travel in the cable or slides.
Below is how I wired mine for two-sided activation. I did contemplate something much fancier with relays and interlocks. However, upon reflection I figured that was gilding the lily and wasn't really needed. I just wired the two switches in parallel, and then I inserted a PTC to guard against the unlikely scenario where two people were operating each switch in opposition. This was a whole lot easier to put together than my first plan. The PTC makes sure we never have a direct short with switches in opposition.
Funny you should mention the 4 x 4 box, I found one at Home Depot that was 4 x 4 x 4, I put the cap and PTC and all the junction of the wires in that box. I pitched the yellow control handle, I had no use for a single control, my bridge is four feet wide.
Since there's four switch machines and power to three different loops on the lift bridge, I have loops of wire hanging between the fixed and movable sections of the bridge to bring power and control in, one set of wires on each side.
