Overview

With the advancement of smart grid technology, the reliability requirements for switchgear are becoming increasingly stringent, and the “unattended” operation and management approach for substations is being adopted more and more widely. Therefore, the DT-JCK series intelligent monitoring device we have developed is a smart, multi-functional, highly integrated monitoring and control unit designed specifically to meet current grid operational needs as well as future development trends. It further enhances the intelligence, networking, digitalization, and informationization of switchgear. The device features functions such as primary circuit simulation, live-line indication and interlocking, voltage detection and phase verification, energy storage status indication, wireless temperature measurement and early warning for contacts and cable terminations, automatic heating and dehumidification, video surveillance of isolating switch opening and closing states, and human-body sensing—all of which make it convenient and easy to use and operate for a wide range of users.

Model Description for Intelligent Monitoring Device of Switchgear Cabinets

Technical indicators

1. Operating temperature: -20 to +65°C;

2. Operating humidity: ≤95% RH;

3. Dielectric strength: ≥AC2000V;

4. Insulation performance: ≥100 MΩ;

5. Electromagnetic interference resistance performance: Complies with the standards specified in IEC 255-22.

6. Operating voltage: AC 85–265V / DC 220V;

7. Humidity measurement range: 20%～100% RH;

8. Temperature measurement range: -20～+120℃;

9. Humidity measurement accuracy: ±3.0% RH;

10. Temperature measurement range for contact/cable connectors: 0℃ to +120℃;

11. Temperature measurement accuracy: ±1℃;

12. Response time: ≤5s;

13. Human proximity sensing time: ≤ 3 seconds;

14. Association between digital input terminals and LCD display: dynamically configurable.

Function Description

Single-circuit simulation

1. The monitoring unit is equipped with a 7-inch color LCD display that can dynamically show the primary circuit diagram inside the cabinet.

2. When the switch operates, the switch status on the monitoring unit’s single-line diagram will change accordingly; meanwhile, the line colors and indicator lights will also change according to the logical state.

3. The types of single-line wiring diagrams can be configured according to the switchgear model. A USB drive can be used to make online modifications to the single-line wiring diagrams, facilitating compatibility with various cabinet types.

    Temperature monitoring

1. The monitoring unit can be configured to connect to a maximum number of wireless temperature sensors. Through the monitoring unit interface, temperature values and temperature curves at each monitoring point can be displayed in real time. The system allows users to set temperature alarm thresholds for each monitoring point. When the temperature exceeds the threshold, the monitoring unit will issue an alarm and record the alarm data.

2. A wireless temperature sensor, installed on the busbar of the switchgear cabinet via a tie-wrap mounting method;

3. Temperature measurement range: 0～+120℃;

4. Accuracy: ±0.5℃;

5. Resolution: 0.0625℃;

6. Temperature measurement cycle: approximately 60 seconds;

7. Power supply: 3.6V lithium battery, operating time > 2 years;

8. Radio Frequency Standard: IEEE 802.15.4.

Video surveillance

1. By installing surveillance cameras inside the switchgear, the monitored images are displayed on the LCD monitor of the monitoring unit, making it easy to observe the opening and closing status of the isolating switch and thereby preventing accidents caused by malfunctions in the isolating switch mechanism.

2. The imaging is clear and the switching operation is convenient, enhancing the reliability of maintenance work while reducing the workload intensity.

Temperature and humidity control

1. It can be equipped with 1–2 temperature and humidity sensors and output contacts, capable of displaying real-time temperature and humidity readings on-site.

2. Users can independently set the upper and lower limits for heating/dehumidification/ventilation output as needed.

3. Equipped with a heater open-circuit detection function;

4. The built-in database can store temperature variation data for the past year.

Live-charge indication and interlocking

1. The energized status of the switchgear can be indicated by the three indicator lights—A, B, and C—on the front panel.

2. Provides two-way energized interlock dry contact functions, which can be connected to electromagnetic locks to meet the five-protection safety requirements.

Energy storage indication

1. When the passive contact is open, the green indicator light illuminates, indicating that the circuit breaker is not energized.

2. When the passive contact closes, the red indicator light illuminates, indicating that the circuit breaker has been energized.

Human body sensing

1. The monitoring unit is equipped with motion-sensing capability for heat sources. When a human body passes within 3 meters directly in front of the unit, the monitoring unit can automatically illuminate its screen for easy viewing.

2. The screen automatically turns off when the moving heat source disappears, saving power and extending its lifespan.

USB maintenance

1. The front panel of the monitoring unit features a USB port that can connect to USB flash drives with capacities of 8 GB or less, enabling you to read database files already stored in the monitoring unit.

2. Additionally, you can use a USB drive to upgrade the system software or perform a single-wire schematic upgrade.