Clause 3 – How to understand the definition of “protective device”

The standard emphasizes “abnormal operation” here. Only devices that operate under “abnormal operation” conditions can be defined as protective devices. Therefore, there are many types of protective devices, including overheating protection devices, overcurrent protection devices, and overpressure protection devices. Overheating protection devices include the thermal link, non- self-resetting thermal cut-out, self-resetting thermal cut-out, thermal cut-out,…

Clause 3 – How to understand the definition of “non-self-resetting thermal cut-out”

non-self-resetting-thermal cut-out: thermal cut-out that requires a manual operation for resetting, or replacement of a part, in order to restore the current.NOTE Manual operation includes disconnection of the appliance from the supply mains. The thermal cut-out is equipped with a temperature-sensitive component, typically a bimetallic strip or a thermistor, which reacts to heat. As the…

Clause 3 – How to understand the definition of “thermal cut-out”

thermal-cut-out: device which during abnormal operation limits the temperature of the controlled part by automatically opening the circuit, or by reducing the current, and is constructed so that its setting cannot be altered by the user. There are three key provisions here. First, the thermal cut-out is a heat-sensing element, second, it can only be…