We had such a device until yesterday. The low price makes here are not paid. My girlfriend has the hot water just before the power goes off normalerweie, used and empty containers be returned to the station. The switch instead remained in the turned-off position due to the heat. She noticed the error until about 5 minutes later, as you could see the glowing heating coil through the measurement window. Conclusion: Fatal if "false" applications. Security should not be cut back at an at otherwise so primitive device that the shut-off mechanism (probably Bimetal) must function reliably.
