Relay Protection Tester Precautions

Relay Protection Tester Precautions

1. Grounding If the test is conducted in an environment where the site environment is harsh, the interference is strong, or the safety requirements are high, before testing, ground the power cord (three cores) with a reliable ground.

2. When the relay protection tester device outputs a large current (such as 3 and the output is greater than 50A or more), use shorter and thicker wiring as much as possible.

3. When the voltage circuit is overloaded or short-circuited, the device will automatically turn off the amplifier circuit and alarm. At this time, please carefully check the loop load.

4. When the output current is high, the software is designed with limited protection to prevent overheating. However, care must be taken to use it, such as outputting large currents too frequently and not having sufficient cooling time in the middle. Obviously the time limit cannot be reliably protected, and the operator must pay attention not to work in the high current output state for a long time or too frequently.

5. When the digital input uses potential input, it has directionality. When the potential input, the common terminal should connect the positive terminal of the potential (such as +KM, etc.).

6. Since IN and UN are connected inside the tester, please be careful not to short IN and UN on the protection device to avoid uneven current distribution and inaccurate test data.

7. When measuring the time relay, if the action or return time is long, use the "manual test" method.

8. For distance protection, if the fault impedance is small, a larger fault current should generally be set. The fault impedance is larger and a smaller fault current can be set to make the fault voltage more appropriate. This also meets the actual operating conditions. Otherwise it may affect the measurement results.

9. Relay protection tester When doing power direction relay or impedance relay test, if using wire current such as Iab to test, please connect Ia, Ib and should also be connected to In, so as to ensure the accuracy of the output current.

10. When doing the zero-sequence power direction test, you can use the stand-alone power direction test menu, or you can use the PC's power direction test menu. At this time, please use the phase voltage and the in-phase current, such as Ua and Ia, to simulate a single-phase fault condition. If you want to test the protection of the microcomputer, you need to select the time before the fault is a few seconds (usually choose 5-15 seconds), so that the tester will output the amount of fault before each test, and then output the amount of fault. If zero-sequence power direction test relay test is performed, it is not necessary to change from pre-fault to fault-to-failure. The pre-fault time can be set to zero.

11. When doing ratio braking of microcomputer type differential protection, since the operating current Id and braking current Iz are combined by the original and paying currents I1 and I2, the test can only be achieved by changing I1 and I2. Change the purpose of Id and Iz. There are generally two ways to set the change of I1 and I2. The first is to set a primary current I1 and adjust the I2 current from large to small. The second is to set a payer current I2, adjust the original square current I1 from small to large. I1 and I2 are determined by their initial value and final value. If the initial value is greater than the final value, it represents a change from large to small, and vice versa represents a change from small to large.

12. When the relay protection tester performs the harmonic braking characteristics of the microcomputer differential protection, there are generally two methods: The first one is in the harmonic differential menu, adding a fundamental wave and two from the original side. The subharmonic hybrid current, in which the second is the braking amount, and the fundamental wave is the action amount. The fixed fundamental wave quantity gradually reduces the secondary quantity or the fixed secondary quantity gradually increases the fundamental wave quantity, to change the action, then Kz = I(2) / I(1). The second is in the differential change menu, adding the fundamental current from the original side, adding the second harmonic current from the payer, the second is the braking amount, and the fundamental wave is the action amount. The other changes are the same as before.

respected user:

Thank you for your attention to our products. In addition to this product introduction, our company also has vacuum degree tester, infrared thermometer, dielectric loss tester, high voltage test transformer, vacuum oil filter, high current generator, etc. If you are interested in our products, welcome to inquire. Thank you!