Splitting (Formatting) Guide

10 марта 2023 г.

(Low Voltage, Switching and Control Equipment for IEC 61439-2.)

The most important choice faced by specifiers in determining low-voltage equipment is to determine the method of compartmentalization. Choosing an inappropriate method of partitioning will at least cause frustration. As a result, the system either costs more than necessary or may not be suitable for implementation.

In general, increasing the degree of partitioning increases the cost. The fact that the highest cost partitioning is selected does not mean that the most appropriate design for the need has been realized. In cases where there is no specific request by the user, the manufacturer must offer the most cost-effective structure to the customer.

In order to select the most appropriate type of forming, the following headings should be determined:

• Location and position of the enclosure 
• Maintenance needs of the enclosure
• Knowledge level of the personnel who will intervene in the board 
• The possibility of energy from the terminal adjacent to the operating or working terminal 
• Difficulty and inconvenience in isolating the entire electro-mounted assembly 
• Comparison of price and advantages with other formulations

The main reason for splitting a system is to facilitate access to a part of the hardware while other parts are in operation and running.

In general, partitioning does not improve the electrical performance of the system, it provides:

• Protection against contact with moving parts of the adjacent functional unit,
• Protection against the passage of solids and foreign substances from one unit of the equipment to another adjacent unit. Verification of partitioning is done through the application of IP testing in accordance with IEC 60529 (IPXXB and/or IP2X).

Determining the optimal method of partitioning for hardware is not an easy thing.

When determining the method of dividing, the following information should be taken into account:

• The consequences of isolating the equipment or part of it, 
• The nature of the task to be performed, 
• The driver's license of the person who undertakes the work when there is energy in the rest of the equipment.

In order to determine the most appropriate form of separation, hardware users and specifiers are encouraged to design the application in detail and then follow the procedure outlined in the Considerations section.

Definitions for Standard Equipment:

Hardware: "Power switching and control hardware" "Low-voltage switching and control equipment used to distribute and control all types of loads designed for industrial, commercial and similar applications where ordinary people are not allowed to use."

This recognition; including floor or wall-mounted electrical distribution boards, control boards and motor control centers using electromechanical and/or electronic components. However, individual devices and individual components that control a single circuit, such as a wall-mounted starter and fuse switch, are excluded.

Functional Unit: "Piece of hardware that encompasses all electrical and mechanical elements, including switching devices, that contribute to the fulfillment of the same function".

"NOTE: Conductors that are connected to the functional unit but outside the compartment or closed protected area (e.g. auxiliary cables connected to the common compartment) are not considered to form part of the functional unit."

It covers all the parts necessary to create a continuous input or output line circuit. It includes the load current transport device(s) and related equipment, the cable shoe and the control devices within the system necessary to form a full circuit. Connections from the functional unit to the electrical power distribution busbars and insulation or curtains to provide this are excluded. It can consist of multiple partitions or closed sandboxes.

Section: "Structural hardware units between two successive vertical boundaries".

It is often thought of as a single full-height column containing one or more functional units. One or more columns are required to complete a piece of equipment.

Lower Part: "Structural hardware units between two consecutive vertical boundaries within a part". Two adjacent and horizontal structural elements, such as the space or space within the column designated and delimited by diagonal elements or shelves.

Section: Closed parts or sub-parts except for openings required for interconnection, control or ventilation.

Enclosure: Reservoir that provides the appropriate type and degree of protection for the targeted application.

Barrier: Part that protects against direct contact from the usual access directions.