What Should Be Noted When Using Microcomputer Relay Protection Tester?

       The output part of the microcomputer relay protection tester produced by GDZX adopts DSP control, which has fast operation speed, strong real-time digital signal processing ability, transmission frequency bandwidth, and high-resolution D/A conversion control. The output waveform has high accuracy, small distortion and good linearity. A large number of advanced technologies and precision component materials have been adopted, and professional structural design has been carried out. Therefore, the device is small in size, light in weight, full-featured, easy to carry, and can be operated after starting up. The mobile test is very convenient.

        When testing the multi-stage overcurrent protection, the test is generally carried out separately section by section, that is to say, when the setting of section I is made, both sections II and III are withdrawn, and then the current is gradually increased until the protection action. The action time measured in the mode is often inaccurate. When measuring the action time, the tester directly outputs the set action value of 1.2 times or more (low voltage protection is 0.8 times or less) to ensure that the protection can start the action. The action time is more accurate.

       When testing distance protection, the short-circuit impedance will only be exported when it is less than the set value. So generally take 0.95 times the fixed value to do the test. It can ensure the reliable export of the protection. When simulating the grounding distance failure, the zero sequence compensation coefficient must be set correctly;

       When verifying the zero-sequence current setting, pay attention to distinguish whether the setting value given in the setting list is 3I0 or I0. If it is I0, it will be displayed in the lower left corner of the test module; if it is 3I0, multiply the value of I0 displayed in the lower left corner by 3 to see if it is the same as the fixed value. For the verification of the fixed value of distance and zero-sequence protection, there is a special verification module behind, which will make the test more convenient. This part of the software has been introduced later.

       When testing the low cycle protection, select the variable frequency, the step of the frequency change is set according to the accuracy requirements, and select the "automatic" method to complete, because the low cycle has the df/dt blocking value, which is not easy to control with the manual method. The frequency drops from 50 to the protection action. It should be noted that the interval time should be greater than the protection action time.

       GDZX is a professional manufacturer of electric power detection equipment. There are many types of instruments and equipment, and a variety of models are available. GDZX is at your service, for more information, visit GDZX's official website: www.en.gdzxdl.com