A high-protection electric energy metering box control method and system and related device
By using a controllable switch in the power metering box to disconnect at the voltage zero-crossing point and then reconnect after a delay, the residual voltage attenuation waveform can be obtained for comparison. This solves the problem of difficult detection of line connection degradation, enables online diagnosis and repair, and improves power supply reliability and protection capabilities.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- SHENHENG ELECTRIC EQUIP CO LTD
- Filing Date
- 2026-06-26
- Publication Date
- 2026-07-24
AI Technical Summary
Existing electricity metering boxes lack effective online sensing methods for line connection deterioration, making it difficult to detect early problems such as joint oxidation and increased contact resistance without affecting power supply continuity, which could lead to potential overheating or fire risks.
When the load current is less than a preset threshold, a controllable switch is used to disconnect at the voltage zero-crossing point and then reconnect after a delay to obtain the residual voltage decay waveform. This waveform is then compared with a reference waveform to extract the decay characteristic deviation, actively diagnose the line connection status, achieve online diagnosis, and perform micro-power outage repair when necessary.
It enables timely detection and handling of line connection deterioration without affecting users' power consumption, improving the active protection capability and power supply reliability of the power metering box, and reducing maintenance workload and potential accident risks.
Smart Images

Figure CN122449431A_ABST