The Siemens 5UB1911 is the basic orange Schuko socket in the DELTA i-system 5UB191x line. It carries the ZSV marking for UPS-backed and safety power circuits but omits increased touch protection — making it the economical choice where the orange colour code is required but touch protection is not mandated by the installation specification.

What does the orange ZSV marking mean?

Orange sockets marked ZSV (Zentrale Sicherheitsversorgung / central safety power supply) are reserved for circuits backed by an uninterruptible power supply (UPS) or a standby generator. In hospitals, data centres, and industrial control rooms, the orange colour lets maintenance staff instantly identify which outlets remain live during a mains failure.

How does this differ from the 5UB1901 orange socket?

Both are orange DELTA i-system Schuko sockets rated 16 A / 250 V in the 55×55 mm format. The critical difference: the 5UB1901 includes increased touch protection (internally shuttered apertures), while the 5UB1911 does not. If the installation code or site policy does not require increased touch protection on colour-coded sockets, the 5UB1911 delivers the same ZSV identification at a lower cost.

When should I choose this over the 5UB1901?

Choose the 5UB1911 when the orange colour code is needed for circuit identification but the socket is installed out of casual reach — for example, above a raised floor in a data centre rack row, inside a locked equipment cabinet, or at ceiling height for projector power. In publicly accessible areas where finger-proof safety is a regulatory requirement, the 5UB1901 with increased touch protection is the correct choice.