Automatic Temperature Rise Test Equipment Double Channel Dc Resistance Test Of Transformer

Power Transformer Double Channel DC Resistance Tester , Temperature Rise Test , Automatic Test

I. Products Description and Application 

Transformer DC resistance test is one of the most important test item in the finished product and semi-finished product factory test, installation and hand-over test in the transformer manufacturing and in the preventive test of the electric power sector it can effectively find manufacturing defects such as looseness, strand lack and broken line in the material selection, welding and connection part of the transformer coils and the hidden danger existing after running.

In order to meet the demand for quick measurement of transformer DC resistance. Our company has developed a new generation of DC resistance tester by making use of own technical advantages, . Using the brand new third-generation power supply technology, it has small volume, light weight and large output current, etc.

The complete machine is controlled by a single chip microcomputer (SCM), the whole machine automatically completes self-inspection, data processing and display, etc., and possesses automatic discharge and discharge indication functions. The equipment has high accuracy and easy operation, it can realize quick measurement of transformer DC resistance.

II. Features

1. The tester has large output current (maximum 20A) and high charging voltage (can output 50V).
2. It has a wide measurement range (0Ω-40KΩ), being able to measure all inductive DC resistances of transformers and instrument transformer, etc.
3. The machine possesses the automatic magnetic assisting function, and uses high-low voltage string excitation for testing the windings of YND11large-capacity iron-core five-legged low-voltage and corner-joint transformer. Internally, the tester automatically connects windings according to the selected phases to be able to realize quick and correct measurement of the low-voltage windings. It can meet the requirement for time during temperature rise test of transformer, with two channels for measurement, real-time sampling and printout, making the temperature rise test be simple and convenient.
4. It has perfected protective circuit and high reliability. With a big color screen to make the displayed data highly legible.
5. The tester features a perpetual calendar, storage of 100 sets of data and automatic temperature calculation, etc., it will not lose data when shutdown. It is also equipped with the U-disk interface for exporting data for check.
6.  It has an RS485 communication interface can cooperate with the control software of the upper computer. It can realize remote control and measurement.
7. The equipment can automatically conduct demagnetization, it will reduce the transformer remanence and avoid the difficulty in closing.
8. The equipment has the protection and alarm function against misconnection of AC380V power supply, it will reduce the damage due to misoperation.
9. It also possesses characteristics like wide applicable temperatures, high accuracy, quake proofing, anti-interference, high stability and portability. It has an audio alarm for discharge and clear discharge indications, these function also can reduce misoperation.

III. Technical Parameters

1.Output voltage: 50V

2.Test current gear: 20A, 10A, 3A, 1A, 15mA

3.Test range at each gear:

      20A   : 0Ω~2Ω 

      10A   : 0.002Ω~4Ω 

      3A     : 0.006Ω~13Ω 

      1A     : 0.02Ω~40Ω 

      15mA: 30 Ω~4KΩ 

4. Test accuracy:  0.2%±0.0002mΩ

5.  Minimum resolution: 0.0001 mΩ

6.  Input power: AC220V±10%；50Hz±1Hz

7.  Working temperature: -20℃-40℃

8.  Relative humidity: ≤90%RH, no moisture condensation