I'll assume you have the blue corded type sensors with the little monitor in the plastic box that you plug in at each bin? Brand escapes me right now.

We don't have any trouble with it in the bins that are filled from our u-trough at our drying system as the grain is coming in rather slow. However, in the bins that we fill with 10" or 13" augers we have to tie them down with baling wire. They have a cable loop at the end for this reason. Takes a little common sense to tie them behind the sweep so you can start up the sweep and then get in the bin and untie them while cleaning it out. No biggie.