Brief introduction of the working principle of the

Introduction to the working principle of the relay protection tester

the relay protection tester is divided into two circuits: the main circuit is adjusted with a large knob and the auxiliary circuit is adjusted with a small knob. The main circuit controls various quantities of its output through the "output selection" key switch on the panel, and each switching of a power transmission helps to solve the problem of excess capacity, The digital voltmeter/Ammeter on the instrument can automatically monitor its output value. The output of the auxiliary circuit is directly adjusted through the control of the output switch, and the measurement can be carried out with a multimeter. The AC220V power input from the principle of the main circuit of the relay protection test instrument enters the input terminal of the dual brush voltage regulator T1 through the output control relay K1 through the fuse, and the power regulated by the T1 large knob enters the isolation transformer T2 (part-time current riser). The current riser is output by three taps, one of which is ACV output, and the rated current is 3A; The tap output voltage can output V DC voltage after rectification and filtering; The second tap is 15V (10a), which outputs a AC current through the relay control of the sensor, Ma AC current through the resistance, a or 0 through the relay conversion, and can also purchase multiple sets of equipment to produce 500mA DC current at the same time; The second tap is a 10V (100a) high current terminal, which directly outputs 100A current through the primary side of the sensor. The circuit has strong load capacity, but the output is slightly overloaded, so it cannot be in a high current state for a long time. Thermal relay calibrator

auxiliary circuit of relay protection test instrument

the auxiliary circuit of relay protection test instrument is the same as the main circuit. The AC220V power supply enters the voltage regulated by the small knob of dual carbon brush voltage regulator T1 through insurance, and the output V or V AC voltage or V DC voltage can be directly adjusted through isolation transformer T4. The rated current of this circuit is 1a. Press the "output control" switch of the auxiliary circuit and adjust the small knob to output

measuring circuit

the output of the main circuit adjusted by the large knob. AC "V", "Ma", "a" drives the lead screw, "a", and DC "V", "Ma", "a" are converted through the relay on the circuit board in the equipment. Each time you switch a gear, the memo can monitor the corresponding output. Among them, the "Ma" gear includes the oil change cycle and maintenance interval of the automobile engine, which can be extended by 50%, and is included in the "a" gear. When in use, double clicking "a" means "Ma" monitoring

time measurement

the device has a built-in 6-digit display stopwatch, and the electric stopwatch can be started internally or externally. When starting internally, press the "output control" switch to start the stopwatch, and short circuit the stopwatch terminal on the equipment panel through the contact to stop the stopwatch. The stopwatch is equipped with a separate power switch, which can be turned off when not in use

audible and visual prompt

the circuit equipment has a built-in audible and visual prompt circuit. When the contact of the tested breaker acts, the contact can be connected to the audible and visual prompt jack of the test box, and the test box will send out an alarm sound or light to prompt the action of the contact of the breaker