The 5UB1515 takes the standard DELTA i-system white SCHUKO socket and adds one deceptively simple feature: a transparent labeling window integrated into the 55 × 55 mm cover plate. A paper strip or card slides behind the window, letting electricians mark the circuit number, distribution board reference, or room designation directly on the socket face. No label printer, no adhesive tags that yellow and peel — just a piece of paper behind a clear plastic window.

When does a labeling field pay for itself?

In a residential bedroom with two sockets, labeling adds no value. In a commercial office floor with 40 identical white SCHUKO sockets spread across 6 circuit breakers, the math changes. During a fault, the maintenance electrician needs to identify which socket is on which breaker without tracing conduits or playing "flip the breaker and walk back." A socket labeled "DB3-C12" answers the question in one second. Similar payoff in server rooms, hospital wards, and university labs — anywhere circuit density makes visual identification the bottleneck during troubleshooting.

What can you put in the labeling field?

The transparent window accepts a standard paper strip approximately 12 × 45 mm. Typical content: circuit breaker number, distribution board ID, room number, or function (e.g., "CT Scanner" or "Rack B14"). Some facilities use pre-printed sheets with the building's circuit plan and cut individual strips to size. The window cover snaps open from the front without removing the socket from the wall — labels can be updated when circuits are reorganized.

Frequently Asked Questions

Is the 5UB1515 otherwise identical to the standard 5UB1511?

Electrically and mechanically, yes — 10/16 A, 250 V, IP20, screwless plug-in terminals, claw-and-screw flush mounting, 55 × 55 mm plate, same DELTA i-system frame compatibility. The labeling window adds approximately 2 mm to the plate depth but stays within the 45 mm minimum box depth requirement. If you need increased touch protection together with a labeling field in i-system, consider stepping up to the DELTA style range (68 × 68 mm), where 5UB1816 offers both in orange.

Does the labeling window affect the IP20 rating?

No — the transparent window is sealed and the paper compartment is isolated from the live terminals behind the cover plate. The socket maintains full IP20 protection.