GB/T 10963.1-2020 Active

This part of GB/T 10963 applies to AC air-type circuit breakers with a rated voltage of not more than 440 V (phase-to-phase) and a rated current of not more than 125 A, and a rated short-circuit capacity of not more than 25,000 A at 50 Hz or 60 Hz, or 50/60 Hz.
This part is, as far as possible, consistent with the technical requirements in GB/T 14048.2—2008.
These circuit breakers are used to protect building line facilities against overcurrent and for similar purposes; they are designed for use by untrained personnel and do not require maintenance.
The circuit breakers in this part are intended for use in environments with pollution level 2.
The circuit breakers in this part are suitable for isolation.
Except for circuit breakers with a rated voltage of 120 V or 120/240 V (see Table 1), the circuit breakers in this part are suitable for use in IT systems.
This part also applies to circuit breakers with several rated currents, provided that the devices that change from one rated value to another during normal operation are inaccessible and cannot be changed to a different rated value without tools.
This part does not apply to:
——Circuit breakers for protecting motors;
——Circuit breakers with a setting current that can be adjusted by the user.
For circuit breakers with a protection level higher than IP20 in IEC 60529, and those commonly used in harsh environmental conditions (such as excessive humidity, heat, cold, or dust deposition) and in dangerous areas (such as areas prone to explosions), special structures may be required.
For technical requirements for circuit breakers used in AC and DC, see GB/T 10963.2—2020.
For technical requirements for circuit breakers equipped with residual current release devices, see IEC 61009-1, IEC 61009-2-1, and IEC 61009-2-2.
For guidelines on the coordination between circuit breakers and other short-circuit protection devices (SCPDs) under short-circuit