Since no earth contact is required in plugs and sockets of rated voltage up to 50V, two keyways instead of one are provided the collar. They are accordingly termed the major and minor keyways. The major keyway is always in the 6 o'clock position. Depending on voltages and frequencies, the minor keyway is always in accordance with table 103 taken from EN 60309-2:1999.

Arrangement of the minor keyway (major keyway 6 o'clock) for various voltages and frequencies using clock-face positions in accordance with table 103 taken from EN 60309-2:1999.

Rated operating voltage of plug or socket in V	Frequency Hz	Clock-face position of keyway (major keyway = 6 o'clock)	Colour code
20 to 25	50 and 60	no minor keyway	violet
40 to 50	50 and 60	12	white
20 to 25 and 40 to 50	100 to 200	4	green
	300	2	green
	400	3	green
	> 400-500	11	green
	Direct Current	10	* violet or white
25	Direct Current*	8 *for portable equipment of electrical incubators - operation with 12V or 24V DC in rescue vans or helicopters.

* MENNEKES offers this device in neutral gray since two colours are specified.

Positions 1 and 9 are reserved for future standards and for design reasons, positions 5, 6 and 7 are not available for use.