The wireless secondary voltage drop/load tester is an intelligent wireless testing instrument designed and developed by our company to automatically test the secondary voltage drop/load of voltage transformers. It replaces the conventional secondary voltage drop/load tester, eliminating the need for long voltage testing cables and greatly avoiding PT secondary short circuit accidents. Created favorable conditions for the safe operation of the substation. The instrument adopts a non GPS wireless synchronization method, which does not require star searching, has fast testing speed, and is not affected by terrain.

1. Automatically measure the secondary voltage drop of three-phase three wire or three-phase four wire voltage transformers through wireless means, without the need for a long voltage testing line to be laid from the instrument to the testing end in the usual way, which can avoid short circuit faults caused by excessively long lines;
2. Non GPS synchronization method, no need to search for stars, fast and convenient to use.
3. Automatically calculate the ratio difference, angle difference, and comprehensive error of the three phases.
4. Automatically measure the load of the secondary circuit of voltage and current transformers.
5. It can automatically detect and store measurement error data caused by test wires under various wiring methods, and automatically correct it in future tests.
6. Specially designed software correction function, which can achieve accuracy correction without hardware adjustment, and can be verified on-site by various levels of power testing and research departments.
7. Various electrical parameters are displayed on the same screen, and voltage, current, phase angle, power factor, active power, reactive power, and apparent power can all be measured; Can display waveform diagrams of various phase parameters.
8. Equipped with harmonic measurement function, it can measure the harmonic content of voltage and current below 32 times.
9. Built in large capacity rechargeable battery pack, which can be powered by the instrument's internal battery pack in the absence of 220V AC power outdoors. Equipped with a fast automatic charger, it can quickly charge the battery pack.
10. The function of indicating the percentage of remaining battery power is not simply a low power alarm.
11. Large screen, high brightness true color LCD display, Chinese character graphical menu and operation prompts for friendly human-machine dialogue, conductive silicone buttons for easier operation, wide temperature LCD with automatic contrast and brightness adjustment, suitable for winter and summer seasons.

Usage environment (2) Environmental temperature: -10 ℃~40 ℃ (2) Relative humidity: ≤ 80%
1. Measurement accuracy
The measurement accuracy of this instrument is level 1.
Differential ratio: Δ f=± (1% × f+1% × δ) ± 0.01 (%)
Angle difference: Δ δ=± (1% × δ+1% × f) ± 1 (min)
Conductivity: G=± (1% × G+1% × δ ± 0.01) mS
Dianna: δ=± (1% × δ+1% × G ± 0.01) mS
Load: S=± (1% × S ± 0.1) VA
Resistance: R=± (1% × R+1% × X ± 0.1) Ω
Reactance: X=± (1% × X+1% × R ± 0.1) Ω

2. Charging power supply: AC 176V~264V, frequency 45-55Hz

3. Measurement range and resolution of the instrument

Test project	Range	Minimum Resolution
Voltage measurement range (V)	40～120.000	0.001
Current measurement range (A)	0.005～6	0.0001
Difference value (%)	-10.000～10.000	0.001
Angle difference (ˊ)	-600～600.00	0.01
Error value (%)	-10.000～10.000	0.001
Revision (%)	-10.000～10.000	0.001