Pin busbar, 16mm2 Connection: 3x (3x (1x phase+HS/FS) touch-safe pin busbar SENTRON 5ST3 as an additional component for residual current protective devices and circuit breakers. These additional components can be mounted universally. They can be installed and connected easily and conveniently. Thanks to the standard touch protection, safety during installation is reliably guaranteed. Optimum technology for your safety - only from Siemens.