Residual current action characteristic tester for residual current protection deviceSuitable for residual current circuit breakers with overcurrent protection for AC rated frequencies of 50HZ and 60HZ, rated voltage not exceeding 440V, and rated current not exceeding 125A, and for measuring the residual operating current and tripping time at rated residual current of AC type residual current protectors or residual current circuit breakers with rated residual current below 500mA.
Test item: (at a reference temperature of 20 ℃± 5 ℃) Temperature control box to be provided by the user.
1. When the residual current increases, verify the correctness of the action: The AC type residual current circuit breaker is at rated voltage, and the residual current steadily increases from 0.2I △ N, and the tripping current is measured.
2. Rated residual current, verification of breaking time: Under the rated current of AC residual current circuit breaker, simulate closing the circuit breaker and test the breaking time.
3. When residual current suddenly appears, verify the breaking time: simulate a closed circuit under the rated current of an AC residual current circuit breaker and test the breaking time.
Preparation before testing:
Instrument inspection: Confirm that the power switch of the tester is in the disconnected state and the connecting wires are intact.
Wiring specifications:
Connect the power cord of the tester to the power side of the leakage protector (AC220V), and be careful not to connect the phase wire (L) and neutral wire (N) incorrectly.
After passing through the zero sequence transformer, the test line is connected to the phase line of the tested circuit.
Parameter setting and testing:
Current gear selection: Select the corresponding gear based on the type of protector being tested (such as AC type, A type, B type).
Action current test:
Press the "mA" switch and turn the adjustment knob counterclockwise to the minimum current value. After turning on the power, slowly increase the current until the protector operates, and record the operating current value.
For the rated residual operating current (such as 30mA), it is necessary to repeat the test 5 times and take the average value.
Action time test:
Adjust the current to the rated value (such as 1I Δ n), press the timer button, and record the time after the protector is activated.
The measurement should be conducted at a reference temperature of (20 ± 2) ℃, with a minimum interval of 1 minute between each measurement.