How do we customize the intelligent control cabinet?

Customization of intelligent control cabinet is a complicated process, and the following are detailed steps:

1. Demand analysis

Functional requirement determination

In-depth communication with customers to understand the specific functions that the intelligent control cabinet needs to achieve. For example, whether it is used for equipment control of industrial automation production lines or for environmental monitoring and equipment management of buildings. If it is industrial automation, it may be necessary to realize the functions of forward and backward control, speed adjustment and fault alarm of the motor; If it is environmental monitoring, it may be necessary to integrate the data acquisition and control functions of various sensors such as temperature, humidity and illumination.

Consider the future expansion requirements, such as reserving a certain number of interfaces to facilitate the subsequent addition of new devices or functional modules.

Clear performance requirements

Determine the working environment conditions of the control cabinet, including temperature range (such as -20℃-60℃), humidity range (such as 10%-90% RH), and whether there are special requirements such as dustproof, waterproof and explosion-proof. For example, the control cabinet used in chemical enterprises may need explosion-proof performance to prevent the spark generated by internal electrical components from causing explosion.

Specify electrical performance indicators, such as working voltage (such as AC 220 V 10%, DC 24V, etc.), current capacity, power factor, anti-interference ability, etc. Anti-interference ability is particularly important for control cabinets working in complex electromagnetic environment, such as control cabinets near large motors, frequency converters and other equipment, which need to have good electromagnetic compatibility.

2. Design stage

electrical design

According to the functional requirements, select the appropriate controller, such as programmable logic controller (PLC), single chip microcomputer or industrial computer. PLC is suitable for occasions with complex logic control and high reliability requirements. Single-chip microcomputer is more flexible and suitable for small and cost-sensitive projects; Industrial computer is used in scenes that require high computing power and data processing.

Design the schematic diagram of the circuit, including the main circuit (used to connect high-power equipment, such as motors, etc.) and the control circuit (to realize various control logic and signal processing). In the design process, the selection of electrical components, such as rated current, rated voltage and breaking capacity of circuit breakers, contactors, relays and fuses, should be considered to ensure that they can meet the normal operation and fault protection requirements of the system.

Draw the electrical wiring diagram, plan the position of each electrical component in the control cabinet, arrange the wiring path reasonably, and minimize the line crossing and electromagnetic interference. For example, high-voltage lines and weak-current lines should be arranged separately, and signal lines should be shielded and well grounded.

Mechanical design

Determine the overall size and structural form of the control cabinet, which should consider the limitation of installation space and the convenience of operation. For example, in a narrow equipment room, the control cabinet may need to be designed as a wall-mounted or compact floor-mounted type; In a large factory workshop, it may be necessary to have a larger control cabinet, with a cupboard door and an inspection passage for easy maintenance.

Choose suitable cabinet materials, such as cold-rolled steel plates and stainless steel plates. Cold-rolled steel plate has low cost and is suitable for general environment; Stainless steel plates are used in occasions with corrosion resistance requirements, such as food processing and marine environment. At the same time, the protection level of the cabinet (such as IP54, IP65, etc.) should be designed to meet different dustproof and waterproof requirements.

Design internal mounting bracket and guide rail to facilitate the installation and fixation of electrical components. When installing the bracket, the bearing capacity should be considered to ensure that the electrical components can be firmly supported; The selection of guide rail should match the installation mode of electrical components, so as to facilitate the insertion, removal and replacement of components.

3. Component procurement

According to the design requirements, electrical components and cabinet materials with reliable quality and budget are selected.

For key components, such as controllers and sensors, try to choose famous brands to ensure product quality and stability. At the same time, it is necessary to check the specification and certification of components, such as whether they have passed CE and UL certification.

Sign a purchase contract with suppliers, and specify the delivery date, quality standards, after-sales service and other terms. In the process of purchasing, we should pay attention to the compatibility of components to ensure that components from different manufacturers can work together normally in the control cabinet.

4. Manufacturing and assembly

Cabinet processing

According to the mechanical design drawings, the cabinet materials are cut, bent and welded. In the process of processing, the dimensional accuracy and appearance quality of the cabinet should be guaranteed. For example, the welding place should be firm and flat, and the surface should be rusted.

Machining installation holes, ventilation holes, etc. on the cabinet, and the location and size of the installation holes should be accurate to ensure the accurate installation of electrical components; Ventilation and dustproof requirements should be considered in the design of ventilation holes, and filters can be used to prevent dust from entering the control cabinet.

Electrical component installation

Install the purchased electrical components to the corresponding positions in the control cabinet according to the electrical wiring diagram. During installation, pay attention to the installation direction and fastening torque of components. For example, the installation of contactors should ensure that the connection of main contacts and auxiliary contacts is convenient, and the fastening screws should be tightened to the specified torque to prevent loosening.

When connecting electrical lines, follow the wiring principle. Lines running in the same direction should be tied neatly with tie straps, and numbered tubes should be put on the ends of the lines to facilitate identification and maintenance. For multi-core cables, pay attention to the color marking and wiring sequence of the core wires.

5. Software programming and debugging

Programming development

According to the functional requirements, the controller is programmed with corresponding programming languages (such as ladder diagram language of PLC, C++ of industrial computer, Python, etc.). For example, for the PLC program to realize automatic production process control, it is necessary to write a sequence control program with clear logic, including start, stop, cycle, fault handling and other modules.

Develop HMI software to realize the interaction between the operator and the control cabinet. HMI can display the running status, parameter settings, alarm information and other contents of the equipment, which is convenient for users to operate and monitor.

Debugging test

First, carry out simulation debugging, and use simulation software or hardware simulator to verify the logical correctness of the program. For example, whether the output of the controller conforms to the expected control logic is checked by simulating the input signal.

Then carry out on-site debugging, connect the control cabinet to the actual equipment or system, and carry out actual operation test. During debugging, it is necessary to check whether the function of the electrical system is complete and whether the performance meets the requirements, such as control accuracy and response speed. At the same time, it is necessary to check whether there are problems such as electromagnetic interference and signal transmission errors.

6. Quality inspection

observational check

Check whether the surface of the cabinet body of the control cabinet is flat and smooth, and whether there are scratches, deformation and paint peeling. Whether the cupboard door opens and closes smoothly and whether the door lock works normally.

Check whether the installation of electrical components is neat and firm, whether the wiring is neat and beautiful, and whether the identification is clear.

functional test

According to the design requirements, the functions of the control cabinet are tested one by one, including manual control function, automatic control function and alarm function. For example, for the control cabinet of a temperature control system, it is necessary to check whether the set temperature, the actual temperature display and the control of heating or cooling equipment are accurate.