BC-2780 Transformer Test Bench Installation Steps
Recommended by Darui Electric
The Transformer Characteristic Comprehensive Test Bench is a specialized test bench developed by our company based on customer requirements for testing transformers. It is a dedicated testing device that integrates no-load short-circuit, ratio, DC resistance, AC withstand voltage, and control in one unit. Various tests can be freely switched, and it features small size, light weight, high precision, and simple testing. Individual test instruments can also be taken out for separate laboratory testing, making it an ideal product for power departments to upgrade.
Working Conditions
Working Power Supply: (Three-phase four-wire) 380V, 50HZ
Working Environment: Ambient temperature: -10 to 40°C; Humidity: ≤85% (no condensation); Altitude not exceeding 1500m, use in an environment without harmful dust or gases.
Note: Please read this instruction manual carefully before conducting tests.
Connect the test power supply properly. This test bench uses three-phase four-wire connection. The test power supply current must be guaranteed above 50A (this test bench is equipped with a 30KVA voltage regulator; if the rated current on the high-voltage side of the tested object exceeds 40A, please use a larger capacity voltage regulator and correspondingly increase the test power supply current). Before conducting each phase test, connect the test object to the test bench with the test connection wires and ground wire, then turn on the power switch of the test bench.
Choose a suitable location for the comprehensive test bench.
Place the mobile chassis of the voltage regulator, hoist the voltage regulator onto the chassis, with the regulator's terminal direction aligned with the two fixed direction wheels of the chassis. Push the regulator to approximately the position of the comprehensive test bench.
Hoist the comprehensive test bench and place it over the voltage regulator (note: the regulator's terminal direction should face the control main board of the comprehensive test bench). Connect the top fixing parts of the regulator with the inner side fixing parts of the test bench using screws.
Push the comprehensive test bench to its specific placement position.
Connect the regulator's incoming phase power (A.B.C.) terminals to the test bench's main board (A.B.C.). Connect the regulator's outgoing phase (a.) to the red large terminal of the electrical parameter meter Ia. Connect the regulator's outgoing phase (b) to the withstand voltage test terminal on the back of the test bench and also to the red large terminal Ib of the electrical parameter meter. Connect the regulator's outgoing phase (c) to the test bench's main board (c.), which returns through the main board to connect to the other withstand voltage test terminal on the back of the test bench and also to the red large terminal Ic of the electrical parameter meter.
Connect the 7-pin connector on the voltage regulator to the 7-pin connector on the test bench's main board.
Connect the black large terminals of the electrical parameter meter to the parameter test terminals on the back of the test bench. After confirming no errors, close the back door.
Connect the power terminals A.B.C.O on the back panel of the test bench to the power supply A.B.C.O. Connect the ground wire. The terminals are respectively connected to the tested object during various tests (refer to the wiring methods for each specific test).
1. Connect A, B, C of the test bench to the high-voltage terminals of the tested object, and a, b, c to the low-voltage terminals.
The transformer's neutral point is not connected to the instrument or to the ground. Connect the instrument's ground wire. Insert one end of the power cord into the power socket on the instrument panel, and connect the other end to an AC 220V power supply. Note: Do not reverse the high and low voltage connections of the transformer!
2. Turn on the instrument's power switch. After a moment, the main menu will appear on the LCD screen, as shown:
At this point, press the "↑" key to select the function menu. Press the "Confirm" key to execute the corresponding function. Note: When a menu is selected, the menu text is displayed in reverse (black background with white text); pressing and releasing a key counts as one key input. 3. Connection method setting. After entering the connection method setting, the LCD screen displays as shown:
At this point, press the "↑" key to select the connection method (single-phase, Yy, Y/d, Dd, D/y). Press the "Confirm" key to save the connection method and return to the main menu. Note: When measuring a three-phase transformer and the connection method is unknown, select Dy.
4. Set the ratio. After entering the ratio setting, the LCD screen displays as shown:
At this point, press the "→" key to select the data digit, and the selected digit is displayed in reverse. Press the "↑" and "↓" keys to modify the data. After selecting a digit, press the "↑" and "↓" keys to cycle the digit from 0 to 9. If it is the * digit, the digit can only cycle from 1 to 9, and 0 will not appear. After selecting the decimal point, press the "↑" and "↓" keys to move the decimal point cyclically. Press the "Confirm" key to save the data and return to the main menu.
5. After warming up for 5 minutes, you can start measuring. After the measurement is completed, the display is as shown:
After each measurement, the instrument automatically saves the data, saving up to 20 data points. If more than 20, all data is cleared and starts from 1. The left side of the * line displays the position of the current data in the historical data, and the right side displays the number of historical data points. The second line shows the group. The third line shows the ratio of phase AB on the left and the relative error of phase AB on the right, and so on. If measuring a single-phase transformer, only the first three lines are displayed. If the relative error of the measured ratio is greater than 10%, it displays ">10%"; if the relative error is less than -10%, it displays "<-10%". Press the "↑" key to view data. Press the "←" key to enter the print menu, where you can print the current data. To print all data, you can clear all historical data. Press the "Confirm" key to return to the main menu. V. Precautions
1. During measurement, do not touch the test object.
2. If the test leads are short-circuited or the high and low voltage connections are reversed, the fuse will blow. After the fuse blows, if you attempt to measure, the LCD screen will display "Measuring, please wait!" and then stop. At this point, turn off the power, replace the fuse with one of the same capacity, and retest.
3. When the instrument is working, if the LCD screen displays disorderly, all keys do not respond, or the measured value is far from the actual value, press the reset key or turn off the power and then restart the operation. 5. If the LCD screen has no character display or the color is very light, adjust the brightness potentiometer to a suitable position. In dark places, you can turn on the backlight.
Ratio Test
First, connect the corresponding connection wires between the tested object and the test bench, connect the ground wire, and after confirming no errors, turn on the test bench power to conduct the test operation. Connect A, B, C of the test bench to the high-voltage terminals of the tested object, and a, b, c to the low-voltage terminals. Turn on the power, close the air switch, turn on the electric bell (warning that the test is starting), set the transfer switch to the ratio position, the ratio indicator light will be on, and the zero position indicator light will be on (if the zero position indicator light is not on, press the voltage reduction button to return the voltage regulator to zero). Press the instrument power switch.
I. Main Functions and Features of the Instrument 1. Automatically measures the connection group. Automatically switches phase sequence. 2. Automatically performs group transformation, directly measuring the ratio of single-phase and three-phase transformers.
3. After inputting the standard ratio, it can automatically calculate the relative error. 4. Measurement results are automatically saved, and test data can be printed.
II. Main Technical Specifications 1. Ratio measurement range: 1 to 10000 2. Group: 1 to 12 points
3. Accuracy: 1 to 1000: 0.2 level; 1000 to 10000: 0.5 level
III.
BC-2780 Operation Method
Note: The above information and technical parameters are compiled and released by Yangzhou Darui Electric Co., Ltd.
