An electromagnet (10) for actuating a hydraulic on-off valve (11), has a wet-type configuration and its armature (31) is displaced in a pressure pipe (18) when a volume of oil is switched through a throttling site (35) in such a way that switching speed can be influenced. The electromagnet (10) has a manual emergency actuation device (43) in the pressure pipe (18). If necessary, the actuating bolts (44) of said device can be engaged with a throttle screw (39) by an interlocking connection (45, 42) in order to displace said throttle screw that is arranged in the armature (31). The switching speed of the distributing valve (11) can be easily regulated from the outside when the electromagnets (10) are mounted, without impairing functioning of the manual emergency actuation device.