1. Product overview

The full name of MNSI switchgear is MNSI type low-voltage withdrawable switchgear.

The design of MNSI switchgear was imported from Germany and is ABB's global standard project for more than 40 years. This low-voltage withdrawable switchgear has been widely used by power users.

This equipment conforms to the International Electrotechnical Commission IEC439-1 "low-voltage switchgear and control equipment", China's GB7251-1997 "low-voltage switchgear and control equipment", China's national standards and machinery industry association JB/T9661-1999 standard content, and in line with CQC's CCC national compulsory certification standard.

2. Product use

As the control of power generation, transmission and distribution, power conversion and energy consumption equipment, and through the capacitor compensation cabinet for reactive power compensation of its main busbar.

3. Environmental conditions of product use

(1) The ambient air temperature is not higher than +40 °C, not less than -5 °C, and its average temperature is not higher than +35 °C within 24h.

(2) The relative humidity of the surrounding air does not exceed 50% when the maximum temperature is +40. At lower temperatures there are larger relative temperatures, such as 90% at +20, but take into account the by

Temperature changes may occasionally produce moderate condensation.

(3) For indoor use, the altitude of the place of use does not exceed 2000m.

(4) It should be installed in a place where there is no severe vibration and impact, and no electrical components are corroded.

This switchgear is suitable for power plants, substations and large buildings, high-rise buildings, airports, hospitals, theaters, stadiums, ports, underground facilities, industrial and mining enterprises, etc., as a three-phase AC 50HZ rated voltage below 2500KVA system for power reception, feeding and motor control. It can meet the computer interface with power use occasions such as power plants with large single capacity, low-voltage power control centers and motor control centers in large-scale petrochemical industries.

Due to the introduction of ABB's advanced technology, and on its original basis to make technical improvements, so that it is more in line with China's national conditions, the cabinet body uses 25mm as the module of the C profile through the connector to form a variety of cabinet structure and drawer units to meet various needs, in the MCC cabinet a large number of high-strength flame retardant engineering plastic components, so that its safety performance is more reliable, at the same time, the foreign functional version is modified, with 200mm as the modulus to be combined, Make it more conducive to the design requirements of PC cabinet and MCC cabinet mixed cabinet, the extraction unit and the cabinet body have a reliable interlocking device, to prevent the switch from pulling the brake with load under the state of switch energization, improve its safety, in addition, the cabinet body is generally assembled after passivation treatment of cold-rolled steel plate, and can also adopt aluminum-zinc copper plate according to the different needs of users.

1. Switchgear type

a. Power receiving and bus unit

b. Power Center Cabinet (PC): Various types of frame circuit breakers at home and abroad, such as AH, CW1, AE, RMW1, ME series circuit breakers are used for power distribution.

c. Motor Control Center Cabinet (MCC): It is assembled from large and small drawers, and the main switch of each circuit adopts a molded case circuit breaker with high breaking capacity or a rotary load switch with a fuse.

d. No power compensation cabinet

2. Drawer type

There are five sizes with a height of 8E (200mm) for modular structure design, and the installation height of its effective components is 1800mm, which makes the overall layout of the cabinet more reasonable and more beautiful.

The 8E/4 combines 4 drawer units in parallel at the 8E height space

8E/2 combines 2 drawer units in parallel at 8E height space

8E assembles 1 drawer unit in 8E height space

16E assembles 1 drawer unit in 16E (400mm) height space

The 24E assembles 1 drawer unit in a space of 24E (600mm) height

The above five drawer units can be assembled in a single cabinet or as a mixture

3. Cabinet introduction

3.1 The basic size of the cabinet

a. Receiver cabinet and contact cabinet

b. Power center (PC) cabinet

c. Motor control center (MCC) cabinet and capacitance compensation cabinet

3.2 cabinet partition design

The MCC cabinet can be composed of single-sided operation or double-sided operation cabinet according to the need, and each cabinet is fixedly divided into three small chambers. That is, the main bus room, the electrical room and the cable room.

3.3 Security protection system

Each cabinet is equipped with a flame-retardant high-density polyurethane plastic functional board, or an electroplated partition plate installed between the main bus room and the electrical room, which is used to effectively prevent the accident caused by the arc and the short circuit between the bus bar caused by the fault of the switch element and make the operation safer.

The upper and lower drawers are separated by galvanized metal plates with ventilation holes, and the smaller 8E/4 and 8E/2 drawers are surrounded by flame-retardant engineering plastic parts, which have a strong insulation and isolation effect between adjacent circuits.

A variety of plastic components are used to support the live sections, which are required to be halogen-free. And it has CTI300 anti-leakage performance.

3.4 Bus system

The switch cabinet can be equipped with two groups of main buses, which are installed in the rear bus room of the switch cabinet, and the two groups of buses can be installed in the upper or lower parts of the cabinet respectively, and the upper and lower groups of buses can be used in different or the same cross-section materials respectively according to the needs of the incoming line. They can be supplied separately, in parallel, or as a backup power supply. The distribution bus (vertical busbar) is assembled in a flame-retardant plastic functional board, which can not only prevent the discharge caused by the arc, but also prevent human contact, and is connected with the main bus through special couplings.

The cabinet is equipped with an independent PE grounding system and an N neutral conductor, which run through the entire device, and are installed at the bottom and right side of the front of the cabinet, and each circuit can be connected to the ground or zero. The installation of the entire bus system is shown in Figure 3. The frame structure is connected by self-tapping screws, which has high grounding reliability.

3.5 Electrical and mechanical interlocking of drawers

The drawer unit consists of a reliable mechanical interlock, controlled by an operating handle, with a clear ready, closed, tested, withdrawn and isolated position. For added security, padlocks can be added to the operating handle after positioning, up to a maximum of three locks can be added.