MNS low voltage withdrawable switchgear

Overview

MNS is a standard; the modular low-voltage switchgear assembled by the factory is suitable for power supply systems with AC 50Hz, rated working voltage of 660V and below, and is used for power generation, transmission, distribution, power conversion and Control of electrical energy consuming equipment.

This device complies with GB7251, IEC439, ZBK36001 and other standards.

Model Description

 

Use ambient conditions

The ambient air temperature should not be higher than +40°C, not lower than -5°C, and the average temperature within 24 hours should not be higher than +35°C.

The relative humidity of the surrounding air should not exceed 50% at the highest temperature of +40°C, and a larger relative humidity is allowed at lower temperatures, such as 90% at +20°C. Occasional condensation effects.

The altitude does not exceed 2000M

When the device is installed, the inclination from vertical should not exceed 5%, and the whole group of cabinets should be arranged relatively flat.

The device should be installed in a place where there is endless strong vibration and shock and where the electrical components are not enough to be corroded.

This device is suitable for transportation and storage in the following temperature range: -25°C to +55°C, not exceeding +70°C for a short period of time (24 hours).

Main technical parameters

 

Product Features

Compact design: accommodate more functional units in a smaller space.

Strong structural versatility and flexible assembly. C-shaped profiles with a modulus of 25mm can meet various structural forms, and the structure and withdrawable units can be combined arbitrarily to meet the requirements of protection levels and operating environments.

Adopt standard; 隹 module design, can install various advanced intelligent monitoring systems for remote management.

The high-strength flame-retardant and high-insulation-strength engineering plastic components are used to effectively protect the safety of the giant.

The mechanical interlocking mechanism of drawers of various sizes conforms to the standard safety regulations, with three obvious positions of connection, test, separation, and safe and reliable.

Cabinets can be arranged back to back.

The guide rail adopts three-section new type guide rail, the drawer is very flexible and convenient to enter and exit, and the built-in devices can be maintained without being separated from the cabinet.

Switchgear Type

Power distribution center cabinet (PC).

Motor Control Center Cabinet (MCC).

Power factor automatic compensation cabinet.

Cabinet structure

The frame of the MNS low-voltage switchgear is a combined structure, and the basic skeleton is assembled from C-shaped profiles. The C profiles are bent and salted from steel plates with E=25mm as the module interval of the installation holes. All the structural parts of the cabinet frame are galvanized (or use aluminum-zinc coated plates), through self-tapping locking screws or 8.8 grade hexagonal bolts It is fastened and connected to form a basic cabinet frame, and the door, clapboard, sealing plate, mounting bracket and busbar functional unit corresponding to the scheme change are assembled into a complete switch cabinet. The internal dimensions, component dimensions and compartment dimensions of the switchgear are all changed in accordance with the modularization (E=25mm). The basic dimensions of the cabinet are shown in Table 2 and Table 3.

The first cabinet of the MNS type combined low-voltage switchgear is divided into three rooms, namely the horizontal busbar room (at the rear of the cabinet), the drawer compartment (at the front of the cabinet), and the cable room (at the lower part of the cabinet or the cabinet). front right). The chambers are separated from each other by steel plates or high-strength flame-retardant plastic functional plates, and the upper and lower drawers are separated by metal plates with ventilation holes, in order to effectively prevent the arcing of the switching elements caused by faults and the short circuit of the busbar or other lines Accidents caused by strict isolation.

The structure design of MNS low-voltage switchgear can meet the requirements of various incoming and outgoing line schemes: top in and top out, top in and bottom out, bottom in and top out, bottom in and bottom out.

 

Busbar System

The horizontal busbar is installed in the independent busbar compartment behind the cabinet. It has two optional installation positions. The busbar can be installed in the upper or lower part as required, or it can be installed in two groups at the same time, and the two groups of busbars can be powered independently , can also be powered in parallel. Each phase busbar can be connected in parallel with 2, 4, and 8 busbars, and the busbar cross-sections are 10X30X2, 10X60X2, 10X60X4 and 10X60X4X2 (mm) for selection.

The vertical busbar is a 50X30X5 L-shaped busbar, which is assembled in a functional board made of flame retardant plastic, which can not only prevent the discharge caused by the arc, but also prevent the human body from contacting, (protection grade IP20) through special connectors Connect with the main bus.

The neutral busbar and neutral protection busbar are installed in parallel in the lower part of the functional unit compartment and vertically in the cable compartment. If the N line and the PE line are separated by an insulator, the N line and the PE line should be used separately.

Drawer Type

There are five standard sizes, all based on 8E (200mm) height; 隹, five kinds of drawer units can be used for single assembly in one cabinet, and can also be used for mixed assembly. The maximum number of drawer units that can be accommodated in a single cabinet is shown in Table 4:

 

 

Drawer compartment

8E/4 and 8E/2 drawer compartment structure includes bottom plate, adapter, guide rail and front rail. The adapter is used for the connection between the main circuit and the control circuit and the branch bus, the connection between the drawer and the cable compartment, and the adapter body has the function of anti-fault arc. There are two types of adapters for drawers, 8E/2 to 63A and 8E/4 to 45A, all with 16-pin control terminals, and 20-pin terminals as required.

The 8E~24E drawer cell structure includes the bottom plate, the metal side plate of the guide rail and the control circuit outlet terminal. The connection between the drawer incoming cable and the branch busbar in the multi-function partition board adopts the row contact, the outgoing cable connection adopts the cable joint (main circuit), and the control cable connection adopts the 16-core or 36-core terminal (secondary circuit) . The main circuit outgoing cable connector is installed on the multifunctional dividing plate.

Drawer Mechanical Interlock

 

 

Installation and maintenance

1. Refer to Figure 6 and Figure 7 for installation.

2. When the device arrives at the destination, first check whether the packing box is complete. If the device is not installed immediately, it should be stored in a dry and clean place.

3. The device is recommended to be installed away from the wall, the installation base plane should be flat, the horizontal error of the foundation channel steel is 1/1000, and the total length deviation is 3mm.

4. It is recommended to use grade 8.8 and tension washers for the bolt fixing method of all conductive parts. The recommended tightening torque is shown in the following table:

5. After the cable is connected, the bottom of the device should be closed to prevent small animals from crawling into the cabinet and causing a short circuit accident.

6. Before the device is put into operation, the following inspections and tests shall be carried out:

A. Check whether the electrical equipment and wiring inside the switch cabinet meet the requirements of the drawing, whether the wire ends are marked with numbers, and whether the wiring is neat and firm.

B. Check whether the installed electrical equipment is in good contact and whether it meets the technical conditions of the electrical equipment itself.

C. Whether the main contacts of the main electrical appliances are reliable and accurate

D. Check the reliability of mechanical interlocks and electrical interlocks.

E. Check whether the withdrawable components are flexible and contact well, and there should be no jamming or excessive operating force.

F. Check whether the insulation resistance of the main circuit and the control circuit meets the specified requirements, and check and test whether the grounding device of the switch cabinet is reliable.

G. Check and test whether all meters and relays operate correctly.

H. Drawers of the same specification should be easily interchangeable without jamming and collision.

 

Unit to Shipping and Storage

A. The device can be hoisted or transported by forklift.

B. The device is not allowed to overturn and suffer severe vibration.

C. If the device needs to move a small distance when it is installed in place, it can be pryed on the four corners of the chassis.

D. It is not allowed to disassemble electrical products and parts in the device at will.

E. It should be prevented from being exposed to rain and damp, and the ambient temperature should be in accordance with the relevant regulations of this sample.

Ordering Instructions

Users should provide the following information:

Main wiring diagram scheme and secondary schematic diagram;

Switchgear arrangement diagram, distribution room floor plan;

The surface color of the switchgear cabinet;

Detailed specifications of main electrical components;

Other special requirements.

Product kits

The switchgear comes with a packing list, product certificate, instruction manual, and necessary drawings. The random accessories include door keys and spare parts provided according to the matching list.

 

 

Main circuit scheme