Safety control system for electric water heater

A safety control system for an electric water heater, comprising:

• an inner tank, having a first pipeline formed inside, wherein the inner tank comprises a water inlet connected to a water inlet pipe and a water outlet connected to a water outlet pipe, the water inlet pipe is connected to a cold water source and is in communication with the first pipeline through the water inlet, and the water outlet pipe is in communication with the first pipeline through the water outlet;
• a heating module, comprising a first heating element, a second heating element, and a third heating element arranged in the first pipeline in sequence, wherein the first heating element is closer to the water inlet;
• a sensing module, comprising a first sensing unit, a second sensing unit, a third sensing unit, and a fourth sensing unit, wherein the first sensing unit is arranged on the water inlet pipe and is configured to sense a first temperature, the second sensing unit is arranged on the first pipeline between the first heating element and the second heating element and is configured to sense a second temperature, the third sensing unit is arranged on the first pipeline between the second heating element and the third heating element and is configured to sense a third temperature, and the fourth sensing unit is arranged on the water outlet pipe and is configured to sense a fourth temperature;
• and
• a control device, comprising a microcontroller, wherein the microcontroller is electrically connected to the first heating element, the second heating element, the third heating element, the first sensing unit, the second sensing unit, the third sensing unit, and the fourth sensing unit, and is configured to:
• verify whether the second temperature is in a first temperature range, whether the third temperature is in a second temperature range, and whether the fourth temperature is consistent with a set water temperature, and control on/off and heating temperatures of the first heating element, the second heating element, and the third heating element until the fourth temperature is consistent with the set water temperature if a result of any of the verifications is no, wherein an upper limit value and a lower limit value of the second temperature range are respectively less than the set water temperature and greater than an upper limit value of the first temperature range.