1. Environmental Conditions for Use

The ambient temperature ranges from -50°C to +40°C, and the average temperature within 24 hours shall not exceed +36°C.

The altitude shall not exceed 2500m.

The relative humidity shall not exceed 50% when the ambient air temperature is +40°C.

A higher relative humidity is allowed at lower temperatures (e.g., 90% at +20°C). Moderate condensation is permitted considering the temperature changes.

The inclination of the equipment from the vertical plane during installation shall not exceed 5°.

The equipment shall be installed in a place without severe vibration, impact, and corrosion.

Note: If the above conditions cannot be met and the user has special requirements, it can be negotiated with our company for a solution.

2. Structural Features

The SWXL - 21 type low - voltage power distribution cabinet is an indoor distribution device installed against the wall with a single - front opening door. Its basic structure is made of bent steel plates and welded angle steels.

A knife - switch operating handle can be installed on the front right side for power cut - off and connection operations. Operating buttons, indicator lights, and display meters can be installed on the cabinet door. After opening the cabinet, all the internal equipment of the distribution box is exposed, which is convenient for maintenance and repair.

In addition to being equipped with air circuit breakers and fuses for short - circuit protection, this distribution box is also equipped with contactors and thermal relays. Grounding screws are welded on both the door and the shell to ensure reliable connection between the shell and the ground.

3.Acceptance, installation, height, and precautions are detailed in the user manual.

After the product arrives, first check whether the packaging is intact. If any problem is found, notify the relevant department in time to find out the cause. For products that are not to be installed immediately, they should be placed in a suitable place according to the regulations of normal use conditions.

1. The bolts for the product installation foundation channel steel shall be prepared by the user. There are connection holes between the foundation channel steel and the cabinet body.

2. After the product is installed and before it is put into operation, it should be inspected and tested:

A. Check whether the coating film on the cabinet body is peeling off; whether the inside of the cabinet is dry and clean.

B. Check whether the on - off of the main electrical appliances and auxiliary contacts is reliable and accurate.;

C. Check whether the selection of the main components and the wiring principle are consistent with the schematic diagram.

D. Use a 500V megger to measure the insulation resistance, which shall not be less than 1MΩ. When measuring, pay attention to disconnecting the wiring of components that cannot withstand voltage and electronic components. 3. Precautions for use

After multiple closing and opening operations of low - voltage air circuit breakers, etc., the main contacts will be partially burned and carbon - based substances will be generated, increasing the contact resistance. The universal low - voltage air circuit breaker shall be maintained and overhauled regularly according to the requirements of its instruction manual.