YKD-40.5GD Insulated Sealed Indoor High Voltage AC Vacuum Circuit Breaker (hereinafter referred to as Sealed Circuit Breaker) is independently designed and developed by our company in accordance with relevant standards and specications such as GB1984, GB/Tl 1022, GB311.1, DL/T593, DL/T402, etc. It has a new generation of 40.5kV combination Vacuum Circuit Breakers in China.

This product has complete functions, stable and reliable mechanical peormance, and is suitable for relatively harsh environments such as high altitude and strong salt spray at the seaside. It can be widely used in wind power generation, photovoltaic power generation, energy storage power stations, urban distribution networks and other projects. It has complete mechanical and electrical interlocking devices, and can achieve safe power distribution function with corresponding switchgear, ensuring the safety of operators and equipment.

1.Model and meaning

2.Product Features

Modular design of product components, with simple, reliable, and consistent cabinet "ve protections";

The arc extinguishing chamber circuit is sealed with high-quality epoxy resin material, and the paial discharge of a single sealed Pole is ≤ 5PC (45kV), which improves the adaptability and reliability of the circuit breaker to harsh environments and can be maintained free during its seice life;

The integrated design of isolation switch, circuit breaker switch, and grounding switch is a high-voltage Vacuum Circuit Breaker with obvious isolation fracture;

The panel adopts a simulated line identication design, which is simple and easy to understand, avoiding misoperation;

A current transformer can be installed on the output side of the switch, which can reduce the size of the cabinet or box transformer;

Intelligent online monitoring units and diagnostic systems can be installed to remotely obtain the operating status of switches through communication modules

Environmental temperature: -25 °C~+40 °C;

Relative humidity: daily average not exceeding 95%, monthly average not exceeding 90%;

The surrounding air is not signicantly polluted by dust, smoke, corrosive or ammable gases, steam, or salt spray;

Places without re and explosion hazards;

Places with eahquake intensity not exceeding 8 degrees and inclination not exceeding 5 degrees.

Note: The above are the conventional usage conditions of GB/T11022. If special usage environmental conditions are required, such as high altitude, concentrated salt spray, and extremely cold and hot environments, the technical design can be customized according to the above requirements.

3. Main technical parameters

4.Operation panel

All status displays and operations are integrated into the operation panel of the equipment. rough an intuitive and concise  human-machine dialogue inteace, all status and operation steps are clear at a glance, allowing for a clear obseation of the exact status of isolation switches, grounding switches, and circuit breaker switches, eectively ensuring the safety of operators and equipment.

5.Interlocking methods for circuit breakers, isolating switches, and grounding switches

Before operation, it is necessa to conrm the position of the lever before proceeding;

If the grounding electromagnetic lock is locked, it needs to be unlocked before operation for grounding;

Circuit breaker opening → isolation switch opening → grounding switch closing → opening cabinet door;

Close the cabinet door → Open the grounding switch → Close the isolation switch → Close the circuit breaker.

Close the cabinet door properly;

Move the lever to the grounding position, inse the operating key into the operating hole of the grounding switch, turn it clockwise to open the grounding switch;

Move the lever to the isolation position, inse the operating key into the operating hole of the isolation switch, turn 

counterclockwise to close the isolation switch;

Move the dial to the blank position, inse the operation key into the energy storage hole, turn the main energy storage clockwise to complete, and then turn the closing knob clockwise to close the circuit breaker.

6.Power outage operation

Rotate the opening knob counterclockwise to open the circuit breaker;

Move the lever to the isolation position, inse the operation key into the probe hole of the isolation switch, turn it clockwise to 

open the isolation switch;

Move the lever to the grounding position, inse the operating key into the hole of the grounding switch, turn counterclockwise to close the grounding switch;

Open the cabinet door (for maintenance).

7.Circuit breaker operation indicator board (operated on the left side of the formal side)

8.Appearance and installation dimensions

YKD-40.5D/T630-31.5 Indoor High Voltage AC Vacuum Circuit Breaker

Left side operation of formal attire (altitude 0-2500 meters)

9.Appearance and installation dimensions

YKD (EP) -40.5D/T630-31.5 Indoor High Voltage AC Vacuum Circuit Breaker (with Lightning arrester and Current Transformer)Left side operation of formal attire (altitude 0-2500 meters)

10.Schematic diagram of box transformer for solid Sealed Vacuum Circuit Breaker

YFGZ35 (EP) -40.5D/T630-31.5 indoor high-voltage AC vacuum circuit breaker is installed inside the transformer box Left side operation of formal attire (altitude 0-2500 meters)

11.Schematic diagram of cabinet door interlocking

Note: Numbers 1, 2, 3, and 4 are cabinet door interlocking accessories provided by our company, which need to be assembled by customers on the door panel of the transformer box.

Common problems with circuit breakers

Common Issues with Circuit Breakers

Circuit breakers are crucial safety devices in electrical systems, but like any mechanical device, they can experience problems. Here are some common issues that users may encounter with circuit breakers:

1. Tripping Frequently: If a circuit breaker trips frequently, it could indicate an underlying issue, such as a short circuit, an overload, or faulty wiring. Overloaded circuits, where the electrical demand exceeds the breaker's capacity, can cause it to trip as a safety measure. Identifying and resolving the root cause is important to prevent repeated tripping.

2. Breaker Won’t Reset: Sometimes, a circuit breaker will not reset after being tripped. This could be a sign of a serious issue, such as a persistent short circuit, a malfunctioning breaker, or a problem with the wiring. If the breaker is stuck in the "off" position, it may need to be replaced.

3. Breaker Trips Without Load: A breaker that trips without any load (electrical devices) connected could indicate internal damage or wear. Over time, the breaker’s components can degrade, leading to faulty operation. In such Cases, replacing the circuit breaker is necessary.

4. Buzzing or Humming Noises: If you hear a buzzing or humming sound coming from a circuit breaker, it could be due to loose connections, an overloaded circuit, or a faulty breaker. This issue requires immediate attention to avoid overheating or fire hazards.

5. Breaker Fails to Trip: A circuit breaker that fails to trip in the event of an overload or short circuit poses a significant safety risk. This problem could be due to mechanical failure, faulty wiring, or wear and tear over time. If a breaker fails to trip when it should, it must be replaced promptly to ensure the safety of the electrical system.

6. Breaker Gets Warm or Hot: Circuit breakers are designed to handle electrical loads, but if they become excessively warm or hot, it can indicate a problem. This could be due to an overloaded circuit, poor connections, or a faulty breaker. Continued overheating may lead to a fire hazard, and the breaker should be checked and replaced if necessary.

7. Breaker Won’t Turn On: If the breaker won’t turn on, it could be because it has been damaged, or there’s an issue with the electrical panel. This may also be a result of the breaker having tripped and being unable to reset due to internal faults or wiring issues.

8. Frequent Power Surges: Power surges often trip circuit breakers. However, frequent surges can indicate an issue with the power supply or a faulty circuit breaker. In such cases, a thorough inspection of the system may be needed to determine the cause.

9. Improperly Sized Circuit Breaker: If the circuit breaker is not properly sized for the load it’s protecting, it may trip too often or fail to protect the circuit adequately. Ensuring the correct size breaker is used is crucial for optimal performance.

In conclusion, while circuit breakers are designed to provide safety and protection, they can experience issues. Regular maintenance, monitoring, and prompt repairs or replacements are key to ensuring your electrical system remains safe and functional.