Microcomputer protective device to electromagnetic interference protection measures are taken, substation, electromagnetic protection to the microcomputer protection, resistance to electromagnetic interference technology measures must be taken, the strict enforcement of microcomputer protection device installation conditions, with the installation of the cable shielding layer, and the ends of the shield must ground at the same time, because the circuit is longer, when grounded at one end, on the other side can produce voltage and current due to electromagnetic interference, which leads to the microcomputer protection action or wrong operation. In order to reduce the possibility of failure and error of the protection device, it is necessary to optimize the design of the microcomputer protection device with reasonable manufacturing process and high quality parts. At the same time, shielding and isolation technology should be adopted to ensure the reliability of the equipment and improve the anti-interference capability.

The grounding of the microcomputer protection device should be carried out strictly in accordance with the provisions. The internal circuit of the microcomputer protection device is an electronic circuit, which is vulnerable to the interference of strong electric field and strong magnetic field. In order to improve the reliability of the microcomputer protection, it is necessary to suppress the interference source, block the coupling channel and improve the anti-interference ability of the sensitive circuit. Fault tolerance is the tolerance of errors, even if there is a local error will not lead to the protection of the device or the wrong operation. Fault-tolerant design makes use of redundant devices running online to ensure the uninterrupted operation of protective devices.

Mistake proofing

The operation lock shall be set on the hardware design. Before normal operation, the operator password and guardian password must be entered correctly, and the names and other information of the operator and guardian can be recorded and saved.

Daily maintenance of relay protection device:

(1) the person on duty should check and check the relay protection device regularly, and record the operation status.

(2) establish the post responsibility system, so that everyone has a post, each post has a person.

(3) clean the relay protection device. Cleaning must be done by two people to prevent accidental collisions with running equipment. Keep a safe distance from live equipment to avoid electric shock and secondary circuit short circuit and grounding accidents.

(4) record the current and voltage sampling values of microcomputer protection once a week. And record the differential current value of differential protection.

(5) regularly conduct infrared temperature measurement on the wiring terminal row of the protection device. To detect the heat generated by poor contact as quickly as possible.

(6) check and print the printer protected by microcomputer every month.

(7) check whether the time of protection device is correct regularly every month. In order to facilitate the fault analysis after the occurrence of the fault.

(8) regularly check the protection fixed value operation area and print out the fixed value list for verification

The relay protection tester can be used separately for ac, dc, low-cycle synchronization, time measurement, power impedance, differential, superposition harmonic, test suite, impedance ladder, zero-sequence protection, system setup and other test items.

Relay protection tester overvoltage relay protection test using the "ac test" program. Single-phase voltage can be used as a variable when the rated voltage of the relay is less than 120V.