一、Necessity of high current temperature rise test

When there are insulation defects in the power equipment running in the distribution network, such as switch cabinets, ring network cabinets, disconnectors, vacuum switches, arc suppression coils, reactors and other high-current equipment, caused by poor manufacturing, aging and external force damage, it will cause equipment temperature rise failure or insulation accidents, seriously affecting the normal operation of the distribution network. In order to prevent such major safety accidents, the temperature rise test is an important test to ensure the service life and safe operation of large current equipment. It is a real way to test whether each power equipment, especially the parts that are easy to heat up through large current, are qualified. In order to ensure the safety and reliability of power equipment, the establishment of a temperature rise test system is particularly important.

二、High current temperature rise test for switches, cabinets and coils

This system is suitable for testing the temperature rise test of high-current switch node equipment such as switch cabinets, ring network cabinets, cable branch boxes, circuit breakers, load switches, disconnectors, and pole switches in the distribution network system. It meets the large current temperature rise test of switch cabinets with a maximum of 4000A, ring network cabinets with a maximum of 3150A, circuit breakers with a maximum of 4000A, load switches with a maximum of 2000A, disconnectors with a maximum of 2000A, pole switches with a maximum of 2000A, current branch boxes with a maximum of 630A, reactors with a maximum of 7200kVar, and arc suppression coils with a maximum of 550kVA. The high-power current-raising equipment conducts a current-through test on the product, the temperature patrol meter monitors the monitoring point in real time and records the temperature curve, and the DC resistance tester completes the resistance measurement of the test site and automatically converts it into a temperature value. The data of the temperature patrol meter and the DC resistance tester are summarized in the program control software to perform functions such as data storage, printing, and query. The industrial control computer controls the coordinated work of each functional module and reads the measurement results through the serial port, and all measurement processes can be controlled and completed on the computer. Finally, the editing, printing and management of the test report can be completed, providing a complete solution for the laboratory to complete the temperature rise test of various electrical equipment.

三、System Features

3.1 Software Features

With login permission control function;

With test product parameters and test parameter input function (must have corresponding permissions);

With system settings and hardware ratio settings (must have corresponding permissions);

With test process recording function;

With operation prompt function;

With automatic test process control function;

With automatic calculation function of test results;

With automatic recording function of test data;

With automatic judgment of whether the test results are qualified;

With automatic generation and printing function of test report;

With local database function;

With historical test record query function;

The test report format is determined by the user, and the test report file is saved in PDF format (or other non-modifiable file format specified by the user) after generation to avoid manual modification of the report content.

3.2 Other functional features of the system

The system has self-detection and protection functions, and can monitor the system’s high and low voltage AC, DC switching quantities, analog quantities and various thermal quantities, and interlock and alarm with the system; the system has overvoltage, undervoltage, overcurrent protection, etc., and will automatically shut down and cut off the upper power grid when a serious fault or fault affects the normal test, may cause the system fault to expand or affect the safety of the equipment, and has sound and light alarms; the system can also record fault information, perform self-diagnosis, and indicate the fault location when a fault occurs;

Automatically adjust the AC constant current source to meet GB 7251.1～ GB 7251.5 standard medium and low voltage switch cabinet (control cabinet with multiple outputs such as GCK, MNS, etc.) temperature rise test, through PLC automatic adjustment of AC constant current source should be able to achieve multiple constant current power supply parallel operation in the temperature rise test (users should be provided with copies of the certification materials for the parallel operation of multiple constant current sources, such as GCK or MNS, etc. temperature rise test);

With three-phase balance system, ensure three-phase balanced output, output current sampling uses imported sensors and PLC integrated control power electronics technology, strong anti-interference ability, high output accuracy, up to 0.5 level;

Equipped with an accuracy adjustment menu, users can adjust the error value by themselves. The programmable AC constant current power supply can realize full intelligent correction, automatically generate multi-segment correction coefficients within the adjustable range of the equipment, and ensure the constant current power supply steady current accuracy;

Can display the three-phase full-range current curve and 32 temperature curve. It can be equipped with a micro printer to print curves and test data on site at any time;

The test report is a WORD format document that can be edited, sorted and printed inside the instrument;

The test module can be customized according to user requirements, and the software can be upgraded free of charge for life.