QJ49a直流单臂电桥
产品概述
QJ49a直流单臂电桥是一款基于惠斯登电桥原理设计的高精度便携式电阻测量仪器，适用于实验室、工业现场及野外作业环境。该产品采用集成电路指零仪和内附工作电源设计，操作简便且稳定性强，可满足1Ω至1.1111MΩ范围内的直流电阻测量需求，典型应用包括金属导体电阻率测定、电机变压器绕组检测、开关接触电阻分析等场景。其紧凑的外形设计（320×260×160mm）与轻量化机身（约4.5kg）便于携带，同时支持外接高灵敏度指零仪以扩展功能。1218
Technical Overview
The QJ49a DC Wheatstone Bridge is a precision portable resistance measuring instrument based on the Wheatstone bridge principle, designed for laboratory, industrial field, and outdoor applications. Featuring an integrated circuit null detector and built-in power supply, it offers user-friendly operation and high stability, covering a measurement range from 1Ω to 1.1111MΩ. Typical applications include resistivity testing of metal conductors, winding resistance analysis in motors and transformers, and contact resistance evaluation of switches. With a compact design (320×260×160mm) and lightweight construction (approx. 4.5kg), it ensures portability while supporting external high-sensitivity null detectors for enhanced functionality. 2722
核心功能
该电桥配备五档量程倍率（×0.01至×100），通过旋转式测量盘实现0.1Ω步进调节，确保测量结果的重复性与准确性。内置电子检流计具备1.5μV/mm的电压分辨率和小于4秒的阻尼时间，可快速响应微小信号变化。针对感性负载（如变压器）测量，设计了先通电后检流的防冲击保护机制，避免感应电势损坏仪器。此外，产品提供微调测量盘（0.01Ω分辨率）用于同名义值电阻的精密比对，满足科研级精度需求。913
Key Features
Equipped with five range multipliers (×0.01 to ×100) and a rotary measurement dial enabling 0.1Ω step adjustment, the bridge guarantees measurement repeatability and accuracy. Its built-in electronic galvanometer delivers 1.5μV/mm voltage resolution and sub-4-second damping time for rapid response to minute signals. For inductive load measurements (e.g., transformers), a protective sequence of power-on-before-detection prevents damage from back EMF. The fine-tuning dial (0.01Ω resolution) facilitates precise nominal value resistance comparisons, meeting research-grade requirements. 1824
应用场景
在工业领域，QJ49a广泛应用于电缆导线品质检测、焊接点电阻评估及大电流分流器校验；在电力系统中，可用于变压器温升试验和接地装置性能分析。其宽温工作范围（15~35℃）与防潮设计适应复杂环境，而机械调零结构和电池电量指示功能进一步提升了现场操作的可靠性。用户可通过标准四端法接线有效消除引线电阻影响，尤其适合低阻值（<100Ω）精密测量。721
Applications
In industrial settings, the QJ49a is widely used for cable quality inspection, weld joint resistance evaluation, and high-current shunt calibration. Within power systems, it supports transformer thermal rise tests and grounding device performance analysis. Its wide operating temperature range (15~35℃) and moisture-resistant design ensure adaptability to harsh environments, while mechanical zero-adjustment and battery status indicators enhance field operation reliability. The standard four-terminal connection method effectively eliminates lead resistance effects, making it ideal for precision low-resistance (<100Ω) measurements. 516
QJ49a直流单臂电桥
的详细介绍
欢迎选购QJ49a直流单臂电桥，我们有优势的价格，的服务！公司承诺，所有商品保证原装正品，一年保修，终身维护！业务咨询:021-63515606,QQ客服:332318574
|
