The on-off cycle in the master timer should go on only for the set time (here it is 18 minutes). Once the master timer goes off, the cycle should stop. To achieve this, the outputs of both the timers are connected to NAND gate N1 (IC3), which gives a low output only when both the timers are giving high outputs.The output pin 3 of N1 is connected to relay RL1 via pnp transistor T1, so the relay energises only when the output from NAND gate N1 is low. As the mains 220V line is taken through relay RL1,the monitor turns off during the 3-second off period after the set time of 10 seconds is over.
Appliance Balance Switch: During the wash period of your washer, there is comparatively little stress to cause the appliance to move around on the floor. In the high-speed spin, a great amount of centrifugal force is build up in the appliance, and it is particularly noticeable if the clothes load is not evenly distributed around the washer tub. Many items such as a heavy blanket or coat could tend to concentrate the load on one side of the inner washer tub. Most washing machines are designed to take an off-balance condition with no bad effects.