Hot and cold water dispenser circuit household appliance circuit

The whole machine is composed of power indication circuit, heating circuit and refrigeration circuit.
    1) Power indication circuit: The power indication circuit consists of LED1, VD1, and Ri. Turn on the power, and add the 220V AC power to the power indicator circuit through the connector XB.
The red power indicator LED1 lights up, indicating that the water dispenser is powered on.
    2) Heating circuit: The heating circuit consists of heating switch sl with signal light HL1, heating thermostat ST1, electric heater EH, protection thermostat
ST2 and heating indicator light LEDZ. Close Sl and turn on the power, HL1 lights up red; EH starts to heat the water in the hot tank. LEDZ
lights up red. When the water temperature rises to 100℃. The sri contact is automatically disconnected, cutting off the power supply of the heating circuit, EH suspends heating, LED2 goes out, and the hot
tank is in the heat preservation stage. When the water temperature drops to 85℃, the ST1 contact
automatically closes, resumes power supply to the heating circuit, LED2 lights up, and
EH performs a new round of heating to keep the water temperature within the 85-100℃ temperature
range.
  ST2 protects against dry burning. When the hot tank is out of service (commonly
caused by cleaning the water dispenser and then inserting a water bottle into it) and the switch Sl is closed by mistake.
When the temperature of the hot tank rises sharply to the operating temperature of the S port, its non-self-resetting
contact will automatically disconnect and cut off the heating circuit to prevent the electric heater from burning out
and the hot tank from burning out, thus achieving the purpose of preventing dry burning. Open the back panel of the drinking machine
and use a screwdriver to press the ST2 reset button to close its contacts
. Then reinsert the water bottle and put it into normal heating.
    3) Refrigeration circuit: The refrigeration circuit consists of refrigeration switch S2 with indicator light HIJ2, refrigeration thermostat ST3, starting relay K, compressor
motor M, overcurrent protector FR and refrigeration indicator LED3. Close S2 and turn on the power, HL2 and LED3 will light green. Since
the running winding of the compressor motor M is connected in series with the coil of the CM hammer-type starting relay K, K generates magnetic force to close its contacts, and the starting winding cs of M
is connected to the power supply. M starts running. After the start is completed, the operating current decreases, the magnetic force of K decreases, causing its contacts to open, cutting off the
power supply of the starting winding cs, and M relies on the operating winding CM to maintain operation and start cooling. First, the compressor compresses the refrigerant into high-temperature, high-pressure steam and sends it to
the condenser. Through heat exchange, the refrigerant becomes a low-temperature and high-pressure liquid. It flows through the throttling capillary and dry filter and then bursts into the cold tank evaporator (wrapped
around the The outer wall of the cold tank absorbs a large amount of heat from the water in the cold tank, causing the water temperature to drop. When the water temperature drops to 40°C, the ST3 contact automatically opens, cuts off
the power of the refrigeration circuit, LED3 goes out, and M pauses refrigeration. When the water temperature rises to 11°C When, the ST3 contact automatically closes and turns on the power supply of the cooling circuit .
LED3 lights up green, and M restarts the cooling operation to keep the water temperature in the 4-11.C area.
    FR is over-current protection. When the compressor motor M When the temperature rises too high or the operating current exceeds the rated value, the FR automatically cuts off the power supply to prevent the compressor
motor from burning out.