Agricultural spraying and insecticide control circuit

The nursery automatic spraying and insecticide control circuit composed of time relays is as shown in the figure. The start and stop time can be set manually. It can spray
for 2 minutes, stop for 30 minutes, then spray 2m/n, stop for 30 minutes, and work over and over again.
    When the start switch SA1 is turned on, the time
relay KT2 coil forms a loop through the KM-1 normally closed
contact and starts to work. After the set
delay time is reached, its KT2-1 normally open
contact closes, thereby making the AC contact The KM coil of the device
is powered to work. Make its neighboring contacts move. Among them
, after the KM-3 contact is closed, the power supply circuit of the water pump motor is connected
, water is pumped and sprayed,
and the auxiliary contact KM-1 is disconnected. The time relay
KT2 is de-energized and its KT2-1 contact is disconnected;
however, since the normally open contact KM-3 of KM has been closed
, the KM coil
continues , so Leave the water pump to continue spraying
. Due to the closure of the KM-2 contact, the KT1 time
relay coil is energized and starts to work. When the set delay time arrives, the KTl-1 contact opens, causing the KM AC contactor coil to lose
power and release. Its KM-3 contact is disconnected, and the water pump motor loses power and stops working. At the same time, due to the reset of the KM-1 normally closed contact ,
the KT2 time relay is energized and starts working.
    If spraying is required immediately after powering on, just move the inching switch SB to start the water pump motor.
    KT1 and KT2 are time relays with digital display. The delay range of this relay is 19h59min, and the adjustment unit is nun.