In an electric heating system with two bimetal discs, what is true about the resetting of the first bimetal disc?

In an electric heating system that utilizes two bimetal discs, the first bimetal disc typically serves as a safety control that activates when the temperature exceeds a certain threshold. This design is critical for preventing overheating, which could lead to equipment damage or even fire hazards.

When the first bimetal disc is tripped due to excessive temperature, it requires manual resetting to restore normal operation. This means that an operator must physically intervene to reset the device after it has responded to an unsafe condition. This characteristic emphasizes the importance of monitoring the system and addressing safety concerns proactively, as only re-establishing the proper function through manual intervention ensures that the heating system does not operate under potentially damaging conditions.

Overall, manual resetting provides a safeguard by ensuring that the operator is aware of the situation and has the opportunity to diagnose and rectify any underlying issues before the system is restarted.