Electrical parameters:
Main circuit voltage level: such as 380V AC (three-phase), 220V AC (single-phase), 24V DC, 48V DC, etc.
Main circuit current capacity/rated current: determines the main switch, contactor, busbar, wire cross-sectional area, etc. A certain margin (such as 20-30%) is usually required.
Control circuit voltage: usually 24V DC (most common, safe, good anti-interference) or 110V/220V AC.
Rated frequency: such as 50Hz or 60Hz.
Short-circuit capacity: The expected short-circuit current that the cabinet needs to withstand affects the selection of the circuit breaker's breaking capacity.
Power consumption/heat generation: The total power consumption of all internal components (PLC, drive, power supply, relay, etc.), which determines the heat dissipation requirements and temperature rise.
Protection level: One of the most important parameters (see the characteristics section).
Physical parameters:
Dimensions: Height (H) x Width (W) x Depth (D). Standard size (such as 800x600x200mm, 2000x800x600mm) or customized.
Installation method: Floor-standing, wall-mounted, embedded.
Material: Usually cold-rolled steel plate (SPCC, thickness 1.5-2.0mm common), stainless steel (SUS304, used in corrosive environments such as food and chemical industry), aluminum (lightweight, good heat dissipation).
Color: Commonly used RAL 7035 (light gray), RAL 7032 (pebble gray), etc.
Weight: Affects transportation and installation.
Function/capacity parameters:
PLC points: Digital input/output points, analog input/output points. Determine the PLC model and the number of I/O modules.
Drive capacity/quantity: The power of the inverter, the number and power of the servo drives determine the spatial layout and heat dissipation.
HMI size/interface: Touch screen size, communication interface type.
Communication interface: Supported bus protocols (such as Profibus, Profinet, EtherNet/IP, Modbus TCP/RTU, CANopen, CC-Link, etc.) and the number of ports.
Expandability: Whether to reserve space and interfaces for future expansion (adding modules, drives, etc.).
Safety function level: The safety standards met (such as IEC 62061, ISO 13849) and the safety levels achieved (such as SIL2, SIL3, PLd, PLe) affect the configuration of safety relays, safety PLCs, etc.

Integration: Integrate controllers (PLC/DCS/PC-Based), input/output modules, power supplies, drivers (inverters, servo drives), human-machine interfaces, communication devices, protection devices (circuit breakers, fuses, contactors, relays), wiring terminals, etc. in a compact space.
Protection:
IP protection level: Prevents solid foreign matter (first digit) and liquids (second digit) from entering. Common examples include:
IP20: Only protects against solids larger than 12.5mm, not waterproof. Used in dry, clean electrical rooms.
IP54: Dustproof (limited intrusion), splashproof. Most commonly used, suitable for most industrial environments.
IP65: Dust-tight, water-proof. Used in dusty environments where water washing may occur (such as food and pharmaceuticals).
Electrical isolation and insulation: Strong and weak current isolation, safety spacing, and creepage distance meet standards (such as IEC 61439) to ensure safe operation and stable equipment.
Grounding: A complete grounding system (protective grounding, working grounding, shielded grounding) effectively suppresses interference and ensures safety.
EMC electromagnetic compatibility: Cabinet design (such as the use of electrical cabinet shielding coating), wiring specifications (strong and weak current separation, shielded cable processing), filters, etc., to ensure that they do not generate excessive electromagnetic interference and can resist external interference.
Reliability:
High-quality components: Select components from well-known brands that meet industrial standards.
Reasonable layout and heat dissipation: Optimize the internal component layout (consider the heat dissipation path and electromagnetic compatibility), and equip fans, air conditioners (heat exchangers) or heat sinks to ensure that the temperature in the cabinet is within the allowable range.
Redundant design: Critical parts (such as power supply, CPU) can be redundantly configured to improve system availability.
Sturdy structure: Ensure stable operation under vibration, impact and other environments.
Maintainability and operability:
Modular design: The main components (PLC, drive, power supply, etc.) are modularly installed for easy replacement and maintenance.
Clear identification: Component labels and line number identification are clear and standardized (in accordance with standards such as IEC 81346).
Easy wiring: Reasonable wiring space, use terminal blocks and wire troughs.
Front door operation/monitoring: HMI, indicator lights, emergency stop buttons and other important operation and monitoring components are usually arranged on the front door.
Convenient door opening method: hinged door, quick opening door, etc.
Safety:
Door lock: Prevent unauthorized personnel from operating.
Emergency stop button: Usually located in a conspicuous position on the cabinet door, in accordance with safety standards.
Safety relay/safety PLC: Realize safety circuits (emergency stop, safety door, light curtain, etc.) to ensure the safety of personnel and equipment.
Electrical interlock: Ensure that operations can only be performed under specific conditions (such as power off when opening the door).
Overcurrent, overvoltage, short circuit protection: achieved through circuit breakers, fuses, etc.
Flexibility/scalability:
Reserved space: Reserve installation space and cable trough space for future addition of modules or equipment.
Reserved interface: Reserve spare communication interface, power interface, I/O interface.
Standardized design: Follow industry standards (such as IEC 60204, IEC 61439) to facilitate upgrades and compatibility.
Environmental adaptability:
Temperature range: Specified operating environment temperature range (such as 0°C - 55°C).
Humidity range: Allowable operating environment humidity range (such as 5% - 95% without condensation).
Corrosion and rust prevention: Surface treatment (spraying, galvanizing) or use of stainless steel.
Vibration/shock resistance: Meet the requirements of specific environments (such as ships and vehicles).