Current Transformer Field

GW20 current transformer field tester is a fully automatic intelligent instrument that is most suitable for error testing of current transformers in the field.

Users no longer need to connect cumbersome current boosters, standard current transformers, load boxes and voltage regulators (or automatic tables), and a single instrument can perform on-site current mutual inductance of 5A~25000A/5A, 5A~5000A/1A

The test time of the whole process (including all measurement points of the rated and lower limit) does not exceed 2 minutes, and its accuracy reaches 0.05S level.

The instrument adopts a 10.1-inch large-screen LCD display, the error of each point can be displayed on the same screen, and all operations can be easily completed by clicking the on-screen menu.

The instrument weighs about 10 kg and can be easily carried.

The instrument can store 1000 groups of test data, and has a dedicated interface to communicate with PC.

Chapter 2 Main technical indicators

Test range: 5A～25000A/5A, 5A～5000A/1A field current transformer (excluding magnetic shunt compensation)

l Secondary load: 2.5VA～100VA CosФ=0.8, 1.0.

l Measurement accuracy: 0.05S level.

l CT, PT load impedance (admittance) measurement accuracy: 2% + 1 word

l Admittance test range: 0～600VA; Impedance test range: 0～100VA

l Display: The liquid crystal display adopts a touch screen of not less than 10 inches, the resolution is better than 1280*800, and supports network port and USB reading.

l Can store 1000 groups of test data, RS-232 interface and PC communication

l For current transformers with unknown transformation ratio, the transformation ratio and polarity can be automatically tested.

l Test speed: complete all test points of each CT, and the test time shall not exceed 2 minutes.

l Lent features a real-time clock that records test times in real time.

l With on-site printing function.

l It has display function of temperature and humidity.

Chapter 3 Service environment conditions

●Ambient temperature: -10℃～40℃

●The relative humidity of the environment does not exceed 80% (23°C)

●Working power supply:

●Voltage: ~220V±10%, waveform distortion less than 5%

●Frequency: 50Hz±2%

●When using, the power supply should not have electric pulse shock, and there should ●be no strong magnetic field unrelated to work around.

Chapter 4 Measuring principle

According to the classic theory of transformer error, referring to the traditional measurement

method of current transformer and the reciprocity principle of current transformer, this instrument

has synthesized their respective advantages and created a set of unique test methods, which

can not only meet the field of transformers of various specifications.

Hot Tags: current transformer field, China, suppliers, manufacturers, factory, price, made in China

3、Instrument reset

There are two ways to reset, one is to power on the reset, the other is to press the reset button reset, the instrument reset, in addition to the data stored in the external memory, other data will be cleared, the instrument back to the initial state.

4、Error of the test

A. First connect the primary and secondary wires of CT (pay attention to polarity), and short-connect other secondary windings. See Appendix 3 for specific connection method.

B. Go to the error test parameter setting page and set parameters one by one test item number: Click the white space to the right of the test item number. A numeric keypad is popped up. Enter the corresponding number with a maximum of 18 characters.

test product model: Click the white space to the right of the test product model and a numeric keypad pops up. Enter a corresponding number (up to 10 characters) or select auto fill.

rated current: a: The rated current is a variable ratio setting. The former is the secondary current value and the latter is the primary current value. Ø rated current: A: The former is the secondary current value and then the primary current value is selected.

C. If the variable ratio displayed is the data to be input, skip to the next item without input; To change the data, click the current value to the right of "Rated current", the current value you need to input will appear, select the corresponding current value rated load: If the voltammetric number displayed is the data to be entered, Ø rating load: skip to the next item without entering. To change the data, click the volt ampere number to the right of "rated load", the volt ampere number you need to enter will appear, click the corresponding data.

lower limit load: Same as the "rated load".

rated current: a: The rated current is a variable ratio setting. The former is the secondary current value and the latter is the primary current value. Ø rated current: A: The secondary current value is selected and the primary current value is selected.

D. If the variable ratio displayed is the data to be input, skip to the next item without input; To change the data, click the current value to the right of "Rated current" and the current value you need to input will appear. Select the corresponding current value.

check accuracy: setting method is the same as "rated load"

 Power factor: Setting method same as "rated load"measurement method: 50Hz test and off-frequency test, the instrument defaults to 50Hz test. If the field interference is strong, please select off-frequency test, and finally click "Start test" to start the test. The interface is as follows:

8、Data management

Click "Data Management" to enter the following interface:

A. Filter: Enter the time you want to query in the blank on the right, click "Filter", you can query the data of the corresponding period;

B. Search: Enter the number you want to query in the blank on the right, click "Search", you can search the corresponding number of data;

C.< : Click "<" to query the last data;

D.> : Click > to query the next data.

E. Delete: Click Delete to delete the current data.

F. Delete All Records: Click "Delete All Records" to delete all data of the database;

G. Print: Click "Print" to print the current data;

H. Upload to host: Through the transmission line, connect the USB interface on the instrument panel and the communication port of the computer, click "upload to host", the data can be uploaded to the supporting software on the computer;

I. Export to USB disk: Insert the USB disk into the USB interface on the instrument panel and click "Export to USB Disk" to download the data to the USB disk.

9 Close down

After completing all tests, turn off the power and then disconnect the CT under test from the instrument.

10 Other

This machine is equipped with special test management software, which can be networked with the MIS software of the power system (zhejiang power users can be networked with the provincial bureau marketing system).

A. Transport

During long-distance transportation, the instrument should be packed into a box, fixed firmly in the box, and equipped with good shockproof measures. Side or upside down is strictly prohibited.

Vibration protection measures are also introduced to prevent collisions or tipping over when a device is transported over short distances.

B. The storage

When not in use, the instrument should be covered with a cover and placed in a dry and ventilated room with no corrosive gas around.

C. Please do not open the instrument shell at will, nor change the internal structure at will. If there is any fault, please contact the manufacturer.

Appendix

Appendix 1：

The specific error limits of the instrument are as follows:

1%         Ratio error：0.2%           Phase error：8分

5%         Ratio error：0.1%           Phase error：4分

20%        Ratio error：0.05%          Phase error：2分

100%       Ratio error：0.05%          Phase error：2分

120%       Ratio error：0.05%          Phase error：2分

Appendix 2：

Purchase this set of equipment, and the following accessories:

1、Power line                               1

2、Special test line                          1

3、Transmission line                         1

4、USBTurn a serial port line                  1

5、Dedicated management software           1

6、The user manual                         1

7、Factory report                            1

Chapter 7 Instructions

1. Boot: Plug in the AC 220V power supply, turn on the power switch, start the system, and then click the icon to enter the operation interface of the instrument.

2, the instrument reset: there are two ways to reset the instrument, one is to turn on the power reset, the other is to press the reset key reset, the instrument reset, in addition to the data has been stored in the external memory, other data will be cleared, the instrument back to the initial state.

3. Wiring: the primary wiring terminal P1(red line) of the instrument is connected to L1 end of the current transformer under test, and P2(black line) to L2 end of the current transformer under test; The secondary wiring terminal S1(red line) of the instrument is connected to S1 terminal of the current transformer under test, and S2(black line) is connected to S2 terminal of the current transformer under test. Short connection of other windings of current transformer, grounding end of instrument should be grounded. 

4. Error test:

(1) Click "Error Test" on the main menu to enter the parameter configuration interface.

(2) After entering the parameter configuration interface, set test item number, test item model, rated load, lower limit load, rated current, calibration accuracy, power factor and whether abnormal frequency and other parameters successively, click "Start Test" after setting.

(3) The instrument enters the test state, after about 2 minutes of calculation, the test is finished, the screen will display the error of each point.

(4) If the prompt "Wiring error, please check wiring" appears in the middle of the test, it means that the secondary wire is short-connected. After rewiring, click "Start test" to restart the measurement. If appear "than mistake, please check the wiring" tips, you should carefully check variable than setting is correct, or whether the parameter input errors and other reasons, click the "start test" and start measuring, if appear in the middle of the test "polarity reverse, please examine the wiring", shows a reverse polarity, simply by exchanging the positions of the secondary wiring, click on the "start test", Start measuring again.

(5) After the test is over and the results are displayed, click "Save data", the group of error data will be stored in the database for future inquiry.

5. CT variable ratio measurement: Click "Variable ratio test" to enter the variable ratio test interface, and then click "Start" to enter the variable ratio test state. After a few seconds, the variable ratio and polarity will be displayed. If no ratio is displayed, it indicates that the measurement result is not in the specified ratio sequence or that the CT is damaged.

6. Load test: a. Connect the secondary wiring to the load impedance under test, not the primary line. B. Click "Load Test" to enter the test interface and choose impedance test or admittance test. Click "Start" to display the measurement results a few seconds later. 

8, temperature and humidity measurement: click "temperature and humidity test", enter the temperature and humidity test interface, click "Start", test results will be displayed after a few seconds.

9. Data management: a. Filter: query by time B. Search: search by number C. Delete: deletes the current data. D. Delete all records: deletes all data in the database. Print: print the current piece of data f. Upload to host: transfer data to computer g. Export to USB flash drive: Downloads data to usb flash drive.

10. Reset: After pressing the reset button, the instrument will restart.

11. Shutdown: After completing all tests, turn off the power first, and then remove the connection between the CT under test and the instrument.