[Al Skierkiewicz]

As others have described, there is a piece of metal between the screw and wire opening. This does not automatically push out of the way when you insert a wire and may need a little help from a small screwdriver. When yo insert the wire, the end musts extend beyond the screw prior to tightening. If it does not, the screw will push down on the metal tab forcing the wire out of the terminal. The ferrules described above work well in this application as they will force the metal tab out of the way when inserted. But here comes a big caveat, do not use these for the FRC PD. The PD is designed for a very particular WAGO ferrule that is available from WAGO suppliers. Any other device is not designed to handle the current due to the unique design of the WAGO PD terminals. In general, these terminals and the PD are intended to be used with bare copper (not tinned) or specific ferrules.