I. Working Principle
The core task of the high-voltage switch tester is to capture various physical parameters generated during the opening and closing operations of the circuit breaker’s operating mechanism. The equipment operation relies on two core technologies: sensor collection and digital signal processing.
When conducting testing, the instrument connects the various phase contacts of the circuit breaker through multiple independent channels, and continuously monitors the changes in the contact opening and closing states. At the same time, displacement sensors installed on the main shaft of the circuit breaker or the connecting rod of the moving contact, mostly using angular or linear displacement sensors, can accurately record the movement trajectory of the mechanism. The instrument is equipped with a high-speed data acquisition system, which synchronously collects all channel signals at a microsecond sampling rate, and then through the embedded processor combined with preset algorithms, calculates and obtains multiple key parameters such as time, speed, and travel distance.
The equipment is equipped with a variable DC power supply specifically for driving the circuit breaker’s operating coil. The voltage output range is DC30V to 270V, which can complete the rated voltage operation test and also conduct low-voltage operation tests, suitable for various testing conditions.
II. Main Testing Functions and Technical Specifications
(1) Time Parameter Measurement
Time parameters are the basic indicators for evaluating the performance of the circuit breaker. The core measurement parameters are as follows:
1. Opening Time: The total duration from the energization of the opening coil to the complete separation of all contacts.
2. Closing Time: The total duration from the energization of the closing coil to the stable closure of all contacts.
3. Synchronization: The maximum difference in action time between each contact, which is the core indicator for determining the consistency of three-phase actions.
The measurement accuracy of these parameters is typically ±0.1ms. For circuit breakers with a voltage rating of 500kV and above, the synchronization deviation must be strictly controlled within 1ms.
(2) Speed Parameter Measurement
The movement speed of the circuit breaker’s contacts directly determines the arc extinguishing performance of the equipment. The speed parameters that the instrument focuses on monitoring include:
1. Initial Separation Speed: The average movement speed of the contacts at the moment of separation.
2. Initial Contact Speed: The average movement speed of the contacts at the moment of contact.
3. Peak Speed: The maximum movement speed within the travel range of the contacts.
The speed data is calculated through differentiation based on the displacement-time curve and requires the use of dedicated sensors for collection and measurement. The typical speed measurement accuracy of the equipment is ±1%.
(3) Travel and Overtravel Measurement
1. Total Travel: The total distance that the moving contact moves from the starting position to the ending position.
2. Opening Distance: The insulation distance between the moving and static contacts when the circuit breaker is in the opening state.
3. Overtravel: The distance that the mechanism continues to move after the contacts complete contact, which is used to ensure the contact pressure.
(4) Current Waveform Analysis of the Opening and Closing Coils
The current waveforms of the opening and closing coils can indirectly reflect the operating state of the electromagnet in the operating mechanism, the movement process of the iron core, and the integrity of the control circuit. Technicians can identify hidden faults and defects such as coil inter-turn short circuits and iron core jamming by analyzing the time nodes and amplitude characteristics of the current waveforms.
(5) Measurement of the Pre-Insertion Time of the Closing Resistor
For circuit breakers equipped with a closing resistor, the tester can accurately measure the pre-insertion time of the closing resistor. This parameter can effectively limit the operating overvoltage. The resistance measurement range of the equipment typically covers 0 to 2000Ω, meeting the routine testing requirements.
III. Key Technical Characteristics
(1) Excellent Anti-interference Capability
The electromagnetic environment in substations is complex, and during the operation of the circuit breaker, transient overvoltages and electromagnetic radiation will be generated, interfering with the detection data. The tester optimizes the anti-interference performance from both software and hardware dimensions. The hardware level adopts optical isolation, shielding grounding, low-pass filtering, etc. for protection design; the software level is equipped with digital filtering and waveform intelligent recognition algorithms, which can stably collect and accurately detect data even in substations with a voltage rating of 500kV and above.
(2) Multi-channel Synchronous Sampling The conventional high-voltage switch tester can support simultaneous detection of up to 6 to 12 independent contacts, with a sampling rate of no less than 10kHz. The time synchronization error of each channel is controlled at the microsecond level, ensuring the authenticity and reliability of the同期 detection data.
(3) Diversified sensor compatibility
The equipment has strong compatibility and can be compatible with various sensor types such as linear displacement sensors， rotational angle sensors， and acceleration sensors. It also has the functions of automatic sensor type identification and automatic parameter calibration， simplifying the on-site wiring configuration process and reducing operational difficulty.
(4) Diverse triggering modes
To meet the detection requirements of different working conditions and different types of circuit breakers， the tester is set with four triggering modes：
1. Internal triggering： The instrument’s built-in power supply outputs voltage is used to drive the circuit breaker to complete the action.
2. External triggering： Relying on the circuit breaker’s own operating power supply， the instrument only collects the external start signal to complete the detection.
3. Sensor triggering： When the contacts generate motion， data recording is automatically initiated.
4. Manual triggering： Suitable for equipment without electric operating mechanisms such as pole-mounted switches.
Post time: May-18-2026