The ZE II is a spring-driven mechanical sterilizing clock that can be set from one to six days at six-hour intervals. On the ZE II, the UES is connected across terminals 1 and 3; the battery is connected across 1 and 2; and the mine unit is connected across 4 and 5. When the UES has concluded its run, a potential is applied across 1 and 3, blowing fuse F, and freeing the escapment to start the ZE II. At the completion of the ZE II run, leaf springs A and B slide into groove C, figure 271; contacts 1 and 2 close, shorting out the battery; and contacts 4 and 5 open, opening the firing circuit. (figure 272)

Figure 270 – ZE II

Figure 271 – Switch Roller for ZE II

Figure 272 – ZE II Wiring Diagram