SN 441011

SN 441011, until 2019 SEV 1011,[1] is the Swiss national standard for AC power plug for domestic use and similar purposes.

[2] The plug-in system defined in the standard for 250 V / 440 V alternating voltage at 50 Hz is structured to be “hierarchically downward compatible”.

On 4 December 2009, the TK23 Technical Committee issued the new revised edition of the Swiss standard SEV 1011:2009 for 10-A plugs and 11/12 sockets to provide, among other things, improved protection against contact with partially insulated pins can.

(A combined socket, which accepts both plugs according to SN 441011 and IEC 60906-1, would, however, be easy to implement, since a further hole for the earthing contact with the smaller distance would only have to be added opposite the previous central hole.)

On December 4, 2009, the technical committee TK23 published the new, revised edition of the then standard SEV 1011:2009 for 10 A plugs and sockets of type 11/12 in order to offer, among other things, improved protection against contact with partially insulated connector pins can.

Originally, T12 plugs and sockets (the most common in domestic use) posed a safety concern.

Since electrical appliances are replaced comparatively often (more often than sockets), the situation should improve overall in a few years.

Geometric construction of the outer shape of the T12 and the T23 plugs
Polarization of the T13 socket when viewed from the front.
Blue (left): neutral conductor
Green-yellow (middle): protective conductor
Brown (right): phase conductor
SN 441011, overview of the hierarchical Swiss System
Pre-2009 T12 plug and pre-2017 T12 socket: fingers can touch dangerous voltage.