High performance Transformer DC Winding Coil Resistance Tester dc resistance tester for transformer

D.C. resistance of transformer is one testing item which must be tested during ex-work test of semi-finished products and final products, installation, hand-over test and preventive test of electric power authority, which can effectively find out existing hidden problems during material selection of transformer coil, welding, looseness of connection part, missing strand, broken wire etc. manufacturing defect and existing hidden problems after operation. In order to meet rapid measurement demand of transformer D.C. resistance, Huazheng company has developed new generation HZ-3340S series D.C. resistance testing meter on basis of its own technology advantage. The instrument applies new brand third-generation of power technology, which is characterized with small volume, light weight, high output current etc. The whole machine is controlled by a single chip microcomputer, which has automatic self-inspection, data process, display etc functions, it also has automatic discharge and discharge indication etc. functions. Testing accuracy of the instrument is high, operation is easy and simple, and it can realize rapid measurement of transformer D.C. resistance.

II.Safety Measures

1. Carefully read the manual prior to use the instrument.

2. The operator of the instrument shall have general application knowledge about electric equipment or instruments.

3. The instrument can used indoor and outdoors, it shall avoid application location with rain, corrosive gas, heavy dust, high temperature, direct sun shine etc.

4. The instrument is high precision instrument, it shall avoid violent vibration.

5. Only professional personnel is allowed to carry out repair, maintenance and commissioning of the instrument.

6. Ater testing is complete, ensure to switch off power supply and disconnect testing wire after discharging alarm is stop.

7. Switch shift of the transformer only after discharge alarm sound stops during measurement of no-load voltage regulating transformer.

8. Prohibit remove and move testing clip and power supply line during testing.

III.Performance Characteristic

1. High output current of the instrument (Max. current output can reach 40A), high charging voltage (50V).

2. Wide measurement scope (0Ω-40kΩ), which can measure transformer, current and voltage transformers etc. all inductive D.C. resistance.

3. The machine is equipped with automatic assist magnetic function, aiming at test of winding of five column iron core low-voltage angle joint YND11 large capacity transformer, high-low-voltage serial excitation method is adopted to conduct test, winding is connected automatically according to selected phase inside instrument, and rapid and accurate measurement of low-voltage winding can be realized. Requirement of time on temperature rise test of transformer can be met, dual channels and phase selection measurement, three kinds of temperature rise timing value mode, real time sampling and printout can be realized, which makes temperature rise test an easy and convenient thing.

4. Equipped with perfect protection circuit, audio discharging alarm, clear prompt which greatly reduce mis-operation.

5. Colorful big screen and touch control, which is simple and convenient, and displayed data are clear and easy to read.

6. Instrument is equipped with perpetual calendar, 100 groups of conventional data storage, 4 times of temperature rise test data storage, automatic temperature conversion function under normal mode, data will not be lost after shutdown. And equipped with "U disk" interface to facilitate export temperature rise data for reference and generating temperature rise curve.

7. The instrument is equipped with RS485 communication interface, in coordination with manipulation software of upper computer to realize remote control measurement.

8. The instrument is equipped with automatic demagnetization function, which reduces residual magnetism of the transformer and avoids difficulties in switching on.

9. This machine has protection and alarm function to protect input against misconnection with AC 380V power supply, which reduces damage on the instruction caused by mis-operation.

10. This machine is characterized with wide applicable temperature, high accuracy, vibration resistant, anti-interference, high stability, convenient carrying etc.

IV.Technical Index

Output voltage:50V

Output current:40A, 20A, 10A, 3A, 1A, 0.3A, 25 mA

Testing scope: 0Ω——1Ω        (40A)

0.001Ω——2Ω     (20A)

0.002Ω——4Ω     (10A)

0.006Ω——13Ω    (3A)

0.02Ω——40Ω     (1A)

0.08Ω——130Ω     (0.3A)

             30 Ω——40000Ω    (25mA)

Accuracy:0.2%±0.0002mΩ 

Min. resolution ratio:0.01 μΩ

Input power supply:AC220V±10%;50HZ±1 HZ

Working temperature:-20℃~40℃

Relative humidity:≤90%RH,no dewing

Volume: 445mm length × 370mm width × 210mm height

Net weight:15kg