MNS Low-Voltage Withdrawable Switchgear Assembly

       MNS distribution cabinet, MNS type low-voltage withdrawable complete switchgear (hereinafter referred to as switchgear) is an advanced low-voltage switchgear developed to meet the demands of the power industry, designed with reference to foreign MNS series low-voltage switchgear and improved. This product complies with the national standards GB7251, VDE660, and ZBK36001-89 "Low-Voltage Withdrawable Complete Switchgear", as well as the international standard IEC439. The MNS type low-voltage switchgear is suitable for various power supply and distribution needs and can be widely used in power plants, substations, industrial and mining enterprises, buildings, hotels, municipal construction, and other low-voltage distribution systems.

Operating Conditions:

The ambient air temperature should not exceed +40°C and should not be lower than -5°C, with the average temperature not exceeding +35°C within 24 hours.
Atmospheric conditions: the air should be clean, with relative humidity not exceeding 50% at higher temperatures of +40°C. Higher relative humidity is allowed at lower temperatures, for example, 90% at +20°C, but occasional moderate condensation may occur due to temperature changes.
The altitude should not exceed 2000m.
This device is suitable for transportation and storage within the temperature range of -25°C to 55°C, and can reach +70°C for a short period (not exceeding 24 hours). At these extreme temperatures, the device should avoid any irreversible damage and should function normally under standard conditions.
If the above operating conditions cannot be met, it should be resolved through negotiation between the user and the manufacturer.
When this device is used on offshore oil drilling platforms and nuclear power plants, a separate technical agreement should be signed.

The circuit breaker should provide at least 5 normally open and 5 normally closed passive auxiliary contacts to meet the interlocking and operation requirements within and between the Xi'an distribution cabinet switchgear, and at least 2 normally open and 2 normally closed passive auxiliary contacts should be reserved for the computer monitoring system and other external systems. The auxiliary contact capacity is: 220V/110VDC 5A. Signal contacts for the energy storage motor's charging and non-charging status should be provided.

Xi'an distribution cabinet current and voltage transformers, current transformer:

(1) Type: Epoxy resin cast.

(2) Rated voltage: 12kV.

(3) Rated current variation: Refer to the design drawing to meet the power supply scheme requirements.

(4) Secondary current: 5A.

(5) Thermal stability current: For main incoming and tie circuits, 31.5kA/3s; for others, 25kA/3s.

(6) Dynamic stability current: For main incoming and tie circuits, 80kA; for others, 63kA.

(7) Rated power frequency withstand voltage: 42kV/min.

(8) Rated lightning impulse withstand voltage: 75kV.

(9) Insulator partial discharge: Not more than 5pC.

(10) Accuracy class: 0.5 (current transformers in metering cabinets are 0.2 class, as determined by the power department).

(11) Rated burden: Determined according to the design capacity of relay protection and measurement.

Xi'an distribution cabinet voltage transformer:

(1) Type: Epoxy resin cast.

(2) Rated voltage factor.

(3) Rated transformation ratio: 10000V/100V.

(4) Rated power frequency withstand voltage: 42kV/min.

(5) Rated lightning impulse withstand voltage: 75kV.

(6) Insulator partial discharge: Not more than 5pC.

(7) Accuracy class: 0.5 (current transformers in metering cabinets are 0.2 class, as determined by the power department).

(8) Rated output voltage: 100V.

Fuse: 1. Rated voltage: 12kV; 2. Rated current: 2A; 3. Rated breaking current: 25kA.

Earthing switch, the earthing switch should be of the same brand as the switchgear.Xi'an distribution cabinet The earthing switch should be equipped with a mechanical open/close position indicator. The operating mechanism should be equipped with a mechanical interlocking mechanism to interlock with the circuit breaker trolley.

1. Rated voltage: 12kV.

2. Thermal stability current: 25kA.

3. Dynamic stability current (peak): 63kA.