Text copied from TM9-1985-2 German Explosive Ordnance 1953 :

Description: The igniter is housed in an ebonite moulding into which is screwed a pressure igniter mechanism similar in operation to the S.Mi.Z.35 igniter. The igniter has a transit cap the wall of which is recessed to accommodate the safety pin. This safety pin is provided with a ring which is folded back over the igniter head. When the igniter is laid in position, the transit cap is removed and the three-pronged "treadspike" which is a push fit onto the striker release plunger is mounted in its place. In place of the detonator cap, as fitted to the S.Mi.Z.35, is housed the glass ampoule in a cup shaped recess in the porcelain fitting which is screwed into the base of the moulding. This ampoule contains an orange liquid which, when released, forms the electrolyte for a small cell. The electrodes of this cell are formed by the lining of the recess and are attached to the two terminal rods. The assembly is completed by the aluminium cup which screws on to the base of the ebonite moulding over the porcelain fitting and terminates in a spike for insertion into the ground. ine of these igniters are wired up in parallel with 2feet 7inches of wire between each igniter and 5feet 3inches of wire leading away from one end of the chain of igniters and terminating in two plugs which are protected during transit by the caps. The plugs fit into sockets in the bridge which screws on to the mine. This bridge incorporates an electric flash housed in the aluminium tube which is protected during transit by the cap. Other components consists of the pressure bar which enables the igniters to be used in pairs. the bridge assembly holder and the pressure plate which is to be used in conjunction with the igniter in soft ground.

Operation: Pressure on the prongs of the electric detonator depresses the release plunger, releasing the two steel locking balls in the head of the striker ad permitting the striker spring to drive the striker into the glass ampoule containing the electrolyte. The electrolyte sets up current between the electrodes and this current induces a flash in the flash tube of the firing bridge, exploding the mine.

Employment: These electric spikes are used to explode the S mines. The two chains of nine igniters used with each S mine greatly enlarge the igniter area for one mine making possible equally effective mine fields although fewer mines are used.

Right photo: nice components of the E.S.Mi.Z40


Photo below © B. Bosman.