Title: Hardware Installation Guide.pdf
HandKey F3 Signal Ground Terminals: 4, 10, or 13revision 6 — 549HandKey ReadersImportant:In either AC or DC power source applications, do not connect the HandKey unit’s ground lug or rear plate to earth ground. This signal is internally connected to the HandKey signal ground, and therefore connection of that signal to earth ground would be a cause for ground loops in multi-dropped configurations.110.1.5PowerIf the HandKey unit is powered from an AC source, then connect the AC Power source to +VIN and -VIN, as indicated in the diagram. Note, however, that this AC source should NOT be shared to power more than one HandKey unit (a single AC source should not drive parallel bridge rectifiers).