Ⅰ.Overview

As transformer is the core equipment in electric power system, its long-term reliable operation is of high significance to the stability and reliability of the whole system.

At present, distribution transformer DC resistance tests, transformer ratio group tests are must-test items of transformer interruption maintenance. To complete the above detection and operation, the transformer DC resistance tester, transformer ratio group tester, loop resistance tester need to be prepared. The Two instruments should be carried for every test. For they’re five independent instruments, each instrument is equipped with specified test wires, which requires separate testing and frequently changing wiring connection, thus wasting a lot of manpower, materials and time.
Our company has innovatively developed the 2 in 1 distribution transformer test system (DC resistance + transformation ratio) powered by large capacity lithium battery. To complete the above two tests, only one set of instrument is needed without frequent connection and disconnection of the testing wires.

Ⅱ.Main Functional Features
1.With one wiring connection, DC resistance tests, transformation ratio tests.
2.DC resistance test function: For Yn type, Y type and △ type winding, it adopts three-phase automatic testing, and calculates the three-phase unbalance rate; The maximum output current is 20A, which can support the very low resistance tests of the low-voltage coil of distribution transformers.
3.Transformation ratio test function: It’s equipped with three-phase, single-phase, Z-type transformer test function; PT/CT transformation ratio and polarity test function; blind test function.
4.With a variety of wired and wireless communication interfaces, it’s convenient for the instrument to expand functions.
5.The instrument adopts embedded Linux operating system, which has high safety, smoothness, ease of use, etc.
6.The instrument adopts A7+M4 dual-core architecture, which not only satisfies the real-time measurement, but also the smooth operation.
7.With 7 inch industrial large screen display, fresh and simple display style design, full touch combined with jog dial operation, it creates comfortable and convenient human-computer interaction experience for you.
8.This instrument uses large capacity lithium battery to provide power and has a built-in charger. 

Ⅲ.Main Technical Indicators
DC Resistance Test：
Output Current：20A、10A、5A、1A、0.1A、≤10mA
Measurement Range ：
Gear 20A，0.5mΩ～ 100mΩ，Gear 10A，1.0mΩ～ 300mΩ
Gear 5A，10 mΩ～ 1.0 Ω，Gear 1A，200mΩ～ 6.0 Ω
Gear 0.1A，2.0 Ω～  60 Ω， Gear ≤10mA，30 Ω～ 50 kΩ
Accuracy：±(reading×0.2% + 2)

Transformation Ratio Test：
Measurement Range：0.9～10000
Accuracy：
±(reading×0.1% + 2)(≤500)
±(reading×0.2% + 2)(＞500，≤3000)
±(reading×0.3% + 2)(＞3000) 
Resolution：
0.9～9.9999(0.0001)       
10～99.999(0.001)
100～999.99(0.01)
1000～9999.9(0.1)  
≥10000(1)

Use Conditions & Appearance：
Power Supply：Built-in lithium battery with capacity of 7.8AH.
Charging voltage：AC220V
Use temperature：-10℃～50℃
Relative Temperature：≤90%, non-condensing.
Weight/Dimension：6.5kg/318×280×204mm