MNS lectric Power Distribution Switchgear

Ⅰ.Overview

The MNS type low-voltage withdrawable switchgear is developed after reference to the Swiss ABB company's MNS series of low-voltage switchgear and comprehensive improvements. It is currently the most advanced low-voltage output switchgear in China. This product is composed of standardized and series of blocks, and has a reliable mechanical interlocking device, which makes the user safer and more reliable when using it.

Ⅱ.Application

MNS series low voltage switchboard is suitable for AC 50~60Hz, 660V and below power system. It is suitable for power plant, substation, petrochemical industry, metallurgical industry, steel rolling ,high-rise buildings, commercial centers, subways, airports, stations, industrial and mining enterprises, drilling platforms, oil extraction platforms, residential areas, commercial streets and rural power and lighting and so on.To receive and distribute power with the function of control, protection and monitor. Different types of switch are used inside the cabinet.

Ⅲ.Environmental conditions

1)Ambient temperature:-5℃-+40°C; And the average temperature in 24h is not higher than + 35℃.

2)Altitude: high voltage ≤1000Meter, low voltage ≤2000Meter (technical department will design specially if exceeds);

3)Relative humidity:≤85%

4)Seismic intensity:≤ magnitude 8;

5)Apply to the places have no fire,no explosion danger, no serious pollution,no chemical corrosion and no violent vibration.

Ⅳ.Specification

No.	Item	Unit	Data
1	Rated voltage	V	400,690
2	Rated insulation voltage	V	660,1000
3	Rated current	A	400~6300
4	Rated current of drawer accessories	A	250,400,630
5	Rated short-circuit current	KA	20~120
6	Insulation: Power frequency withstand voltage	V	Main circuit:2500; Auxiliary circuit 2000
7	Protection class		IP4X
8	Operating mechanism		Manual mechanism; Electric mechanism
9	Operational power supply	V	DC:110,220; AC:110,220
10	Overall dimension(Width*Depth*Height)	mm	600(800,1000)x800(1000)x2200
11	Weight	KG	300~1000

Ⅴ. Composition and Features 

Cabinet: The cabinet body of the switchgear is made of steel plate or aluminum-zinc plate and processed by CNC machine tools, which not only has high precision but also has strong anti-corrosion and oxidation resistance. The overall weight of the cabinet is lighter than other equipment cabinets, and the mechanical strength is high. The processing and production cycle is short. , The parts have strong versatility, and the area of ancient land is small, which is convenient for production organization.

Compartment: The main electrical components of the switchgear have independent compartments. According to different functions, they are divided into handcart room, busbar room, cable room, and relay instrument room by partitions. The rooms are separated by metal protective plates. The compartment shells are all independently grounded, and the protection level of each compartment reaches IP2X; except for the relay room, the other three compartments have their own pressure relief channels.

Interlocking device: The joint pins between the main switch, handcart, grounding switch and cabinet door all adopt compulsory mechanical locking methods to meet the "five prevention" function.

The breaker handcart can only be closed when the circuit breaker is in the open/test position or working position; and after the circuit breaker is opened, the propulsion mechanism of the handcart cannot be operated and the handcart cannot be moved to prevent loading Push-pull circuit breaker handcart.

Link ground device: In the cable room, a separate 6x50mm2 grounding busbar is provided. This busbar can run through adjacent cabinets and make good contact with the cabinet to prevent electric shocks. Human body impedance and environmental conditions, ensure the normal operation of the power system, and prevent lightning strikes. The hazard of static electricity occurs when lightning occurs

Heater: In order to prevent the danger of condensation in a climate with high temperature or humidity changes. Install heaters in the circuit breaker room and the cable room respectively for use in the above-mentioned environment and to prevent corrosion. The high-voltage switchgear has a heating device for easy control of temperature and humidity. When the temperature of the switchgear is lower than the required value and the humidity is higher than the required value, the heating device is activated.

Compartment in the switch cabinet :

1. Withdrawable handcart: The handcart frame is formed and assembled with high-quality cold-rolled steel plates. The handcart is equipped with a vacuum circuit breaker and other auxiliary equipment. The handcart frame is equipped with a screw nut propulsion mechanism and an ultra-high clutch.

2. Circuit breaker compartment: A special track is installed in the circuit breaker compartment for the handcart to move, so that the circuit breaker handcart can slide and be fixed in the compartment through a rotatable screw-nut mechanism.

3. Busbar compartment:The main bus bar is led from one switch cabinet to another switch cabinet and fixed by the branch bus bar and static contact section. When passing through the adjacent cabinet, the bus bar is fixed by the wall bushing, which can effectively prevent the accident from spreading, and at the same time assist the main bus bar. Supporting role.The busbar adopts shrinkage type casing or fluidized coating process, and the phases and connectors are equipped with insulating sleeves made of flame-retardant materials to form a reliable composite insulation.

4. Cable compartment: Current transformers, lightning arresters and grounding switches can be installed in the cable room. The ample space is convenient for the installation and connection of multiple cables.

5.Relay room:The internal and external panels of the relay can be equipped with secondary components such as control, protection components, metering, display instruments, and live monitoring displays.

Precautions for power transformer operation:

1. No overload operation: Long-term overload operation will cause the coil to heat up, gradually aging the insulation, and cause a short circuit.

2. Frequent inspection of insulating oil: oil quality should be tested regularly, and unqualified oil should be replaced in time, or other measures should be taken.

3. Prevent the insulation aging damage of the transformer core, and the insulation aging caused by the long-term heating of the core.

4. Prevent the insulation from being damaged due to careless maintenance. If scratch damage is found, deal with it in time.

5. Ensure that the wires are in good contact, and poor contact will cause local overheating.

6. To prevent lightning strikes, the transformer will burn out due to insulation breakdown.

Ⅵ.Ordering notice:

Please provide system capacity, system voltage, electric scheme, function requirement, configuration requirement when you decide to order.