Selecting an appropriate three-phase multi-functional electrical detection instrument requires comprehensive consideration from multiple dimensions based on actual usage requirements. The core selection points can be divided into the following eight aspects, and the key concerns in each dimension are as follows:
1. Core measurement parameters and accuracy
The basic measurement parameters should cover three-phase voltage, current, frequency, as well as active, reactive, and apparent power. It should also have the ability to measure power factor and energy, meeting the basic electrical detection needs.
The accuracy level should be selected according to the usage scenario. For high-precision measurement and standard transfer scenarios, a 0.1% or 0.2% S-class accuracy can be chosen; for general power quality analysis and energy management scenarios, a 0.5% or 1.0% accuracy is sufficient.
Harmonic analysis capability is the core assessment indicator. The harmonic frequency should at least meet the national standard requirements up to 50 times. If there are higher detection requirements, an instrument capable of measuring up to 128 or more harmonics can be selected; for the detection of equipment such as frequency converters, it is necessary to confirm that the instrument has the ability to measure inter-harmonics.
The detection of power quality indicators requires attention to the direct measurement and recording capabilities of the instrument, and it is necessary to confirm that it can directly obtain indicator data such as flicker (Pst/Plt) and voltage imbalance degree, rather than only calculating the results.
2. Sampling rate and bandwidth
The sampling rate should prioritize higher specifications. High sampling rate can more accurately capture transient switching, the starting point of voltage drop, and other instantaneous faults and waveform details, meeting the needs for refined detection.
The bandwidth should at least cover up to the 50th harmonic corresponding to 2500Hz. If higher-frequency interference analysis is required, a wider bandwidth specification should be matched.
3. Data recording and storage
Attention should be paid to the multi-mode recording capabilities of the instrument, including trend recording of basic parameters at fixed time intervals, rapid recording of waveforms before and after faults based on thresholds, and power consumption statistics mode specifically for recording electrical energy data, to meet the data recording requirements of different detection scenarios.
The storage capacity should take into account both built-in storage and expansion capabilities. The built-in memory should meet the basic storage requirements, and it should also support external storage devices such as USB drives and SD cards for expansion to achieve long-term monitoring data storage.
4. Connection and input methods
Voltage input is divided into direct input and access through a voltage transformer (PT). The direct input standard specifications are 600V or 1000V CAT III/IV, and the appropriate method can be selected based on the actual detection environment.
Current input is preferably with a flexible current clamp (Roessig coil), which does not require circuit disconnection, is safe and convenient to operate, and has a wide range of measurement capabilities; fixed current transformers (CT) have higher accuracy and are suitable for installation in fixed cabinets, but have poorer mobility. The actual selection should be based on the measurement current range from a few amperes to several thousand amperes, matching the corresponding current clamp specifications.
5. Display and operation interface
The display screen should prioritize a color touch screen, which is more intuitive for operation and provides clearer waveform and parameter display.
The operation keys should be logically clear and easy to operate, reducing the difficulty of on-site detection.
It is necessary to confirm that the instrument has multi-channel display capabilities, which can simultaneously present real-time values and waveforms of multiple parameters, facilitating synchronous observation and analysis.
6. Communication and software functions
The communication interface should at least be equipped with a USB interface. If there is a need for remote control or data transmission, advanced models with interfaces such as Wi-Fi, Bluetooth, or Ethernet can be selected.
The functionality completeness of the accompanying PC software is a key consideration point. It should be confirmed that the software can conduct in-depth data analysis and generate professional detection reports in accordance with national or international standards, improving the overall efficiency of the detection work.
7. Safety certification and portability The safety level must comply with the IEC/EN 61010-1 standard and possess safety certifications of CAT III 600V/CAT IV 300V and above, providing a guarantee for the safety of on-site operations for operators.
For the usage requirements of mobile measurement, the portability of the instrument needs to be focused on, including basic indicators such as weight and volume. At the same time, the robustness of the instrument should be considered, and preferred specifications with protection levels such as IP54 should be selected to adapt to different on-site detection environments.
VIII. Comprehensive Cost Performance and Service Assurance
Based on the actual application requirements and budget range, find a balanced point among the instrument’s functions, performance specifications and price, taking into account both usage requirements and cost control.
The completeness of after-sales service is of vital importance. Attention should be paid to the convenience of instrument calibration, fault repair, as well as the professionalism and response efficiency of technical support to ensure the long-term stable use of the instrument.
Post time: Jan-23-2026