The ZE IVa is a 60-day sterilizer developed to replace the ZE IV, and it operates on the same principle. When the ZE IVa is used in the OMA mine, the detonator is connect-ed across terminals 45, figure 283. The clock is started by cam 39. At the end of its run, striker D, figure 284, is released in the same manner as in the ZE IV, disengaging the knife switch A and opening the detonator circuit, thereby disarming the mine.

Figure 281 – ZE IVa for OMA Mine

Figure 282 – OMA/K Mine with ZE IVa

Figure 283 – Diagram of ZE IVa

Figure 284 – ZE IVa, Section A-A