When measuring circuit breaker operation time on site, readings from multiple instruments often differ by a few milliseconds. This is usually not a problem with the circuit breaker itself, but rather caused by test lead compensation, power supply fluctuations, or different triggering methods. The following summarizes several issues commonly encountered by operation and maintenance personnel from the perspective of engineering parameters.
The time test range is 10ms to 12s, with a resolution of 0.1ms and time test accuracy of ±0.1% reading ±0.1ms. Parameters such as closing, opening, and three-phase asynchronism can all be covered, and bounce time and arcing time are also within the recording range.
If an external DC panel is required on site, wiring and voltage adjustment are both troublesome. This instrument has a built-in operation power supply with continuously adjustable output voltage of DC 20–270V, which can directly drive the opening and closing coils of circuit breakers with different control voltage levels, eliminating the need for an additional power box and reducing interference introduced by wiring connections.
Two options are available: linear travel sensors and angular displacement sensors, adapting to different operating mechanisms. The travel measurement range is 0–1000mm, and the speed measurement range is 0–20m/s. It can calculate just-opening and just-closing speeds, average speed, and maximum speed, providing data for judging the mechanical state of circuit breakers.
The instrument adopts a portable structure, and the test lead interfaces are marked by phase. After connecting the opening and closing coils, auxiliary contacts, and sensors, data acquisition can begin. The input channels feature photoelectric isolation, which can reduce false triggering in the electromagnetic environment of substations.
