The main object of microcomputer relay protection and maintenance testing machine is the relay protection and maintenance equipment of 220kv and below high voltage transmission lines. Through the simulation system to detect all kinds of faults, output three-phase voltage, current or dc test voltage operation, simulation of single-phase grounding, two-phase short circuit, three-phase short circuit and other fault occurrence and elimination process, simulation of the fault process of current and voltage changes, check the maintenance equipment of the various action functions. Before the operation of the microcomputer relay protection tester, the operator shall carry out risk point analysis and operation, explain the task division, operating address, operating equipment status and matters needing attention, and check whether the arrangement of safety measures meets the requirements. Before operating the device, the name of the device must be checked to prevent incorrect intervals and incorrect operation maintenance. The microcomputer relay protection tester USES voltage and current to suddenly change from the normal operating value to the serious disease value. At the same time, the echo state and echo speed of relay protection equipment are tested, and various maintenance equipment, such as voltage, current, negative sequence, impedance and direction, are verified. The tester shall not move the switch operating handle, trolley switch, ground button alarm, alarm bell, reset button, tripping pressure plate, fuse, voltage switch, etc., when operating in the substation or on the spot. If the above equipment is operated as required, it shall be operated with the permission of the operator concerned and under the supervision of the operator.

Do not drill holes in the operation maintenance panel when drilling near the operation maintenance panel or vibrating on the operation maintenance panel. When necessary, anti-vibration measures shall be taken and relevant maintenance shall be stopped. In the control panel or maintain transfer plate before and after the aisle or place the microcomputer relay maintenance test instrument, it is necessary to maintain satisfactory interval, by presenting false touch form switch mistrip microcomputer relay maintenance test instrument as the widely use: all the individual elements of a secondary scheduling test (current, voltage, time, differential, balance, negative sequence, interval and power direction, inverse time, frequency, period, reclosing relay etc.). The whole group of transmission can simulate various simple or complex transient, *, conversion barrier, and can superimpose transient dc component on the fundamental wave. It can superimpose each harmonic arbitrarily, and can control the initial Angle and content online. Phase output of different frequency ac, ac and dc dual purpose. Dedicated low-cycle units for microcomputer low-cycle low-voltage load reduction maintenance test, various maintenance time characteristics of active scanning, power and impedance maintenance characteristic curve scanning. Active test of differential sharing and harmonic braking characteristics in mains transformer maintenance. The whole set of interval, zero sequence, overcurrent overhaul active test, user programmable test unit, in order to satisfy the special test use, for example, the test of the motor loss of magnetic step, anti-excitation, reverse power and the same period maintenance test.