Can the DC fan case be customized? Control logic should also be written into the plan
Direct answer: DC fan cabinets can be customized, but the scope of customization is not just the size of the cabinet and the direction of the air outlet. The driver model, speed control signal type, interlocking logic, fault feedback method, minimum operating air volume and action after disconnection are all customized content. If you only customize the cabinet and ignore the control logic, the equipment may not be connected to the original control cabinet after it arrives, or the operation mode may not match the project requirements. The control logic should be confirmed together with the cabinet structure at the planning stage.
Aili Industry is discussingWhen customizing a DC fan chassis , the project is usually required to list the actual operating status and control requirements, and then confirm the executable configuration based on the motor, fan, driver and cabinet structure.
List the actual operating status first, and then talk about customization
The customization requirements for DC fan boxes often do not start with 'what size box do I want?' but rather with 'what operating states this equipment will go through.' A typical ventilation system may include the following states:
The work shift is at full load: During the production period, the terminal demand is the largest, and the fans operate according to the design conditions.
Night duty: During non-production periods, only the minimum air exchange or pressure difference needs to be maintained, and the fan speed is reduced.
Equipment shutdown: The system does not need air supply and the fan stops, but the control power may still need to be maintained.
Fault status: sensor disconnection, driver alarm or communication interruption, how should the fan act?
Each state should clearly specify the expected air volume or pressure, allowable speed range and switching conditions. Only 'adjustable speed' is required, and the control logic is decided on site, which can easily lead to insufficient signal points and electrical interfaces. For example, the duty mode requires low-speed operation, but whether the fan can overcome the resistance of the filter section at the lowest speed needs to be calculated at the planning stage. System end configurationWhen using HEPA/ULPA high-efficiency filters , the initial resistance of the filter and the resistance at the end of use will affect the low-speed operating point. When the process requirements are higher, it can be evaluatedDoes the ULPA ultra-high efficiency filter meet the requirements?
New construction and renovation have different constraints
For new projects, interfaces can be unified during the design phase of equipment, power supplies and control cabinets. The speed control signal type, terminal definition, communication protocol and fault feedback method of the fan box can all be determined at the drawing stage. Control cabinet space, drive cooling and cable routing can also be planned in advance.
The renovation project was limited by the original foundation, power supply and control cabinets. It is necessary to first take inventory of the original control signal type, power supply capacity, flange size and maintenance space. If the original system uses analog control, is the new driver compatible? If the original system only has start-stop control, does it need to add a speed control signal line? If the original control cabinet does not have space to install the driver, does it require an external control box. These issues must be confirmed before modification.
The installation and heat dissipation conditions of the driver also need to be determined in the structural plan. When the driver is installed in the box, the temperature inside the box may be high, and the heat dissipation method needs to be confirmed. When the driver is installed in the control cabinet, the space and ventilation conditions inside the cabinet must meet the requirements. These constraints will affect the structural design of the customized solution.
What to do when control is abnormal
Controlling the action when an abnormality occurs is the most easily overlooked part of DC fan chassis customization. After the duty mode signal is lost, should the fan maintain the current speed, return to the preset speed, or stop? Different choices correspond to different control logic and wiring methods.
Especially in scenarios with minimum air supply or pressure difference requirements, control failure actions must be confirmed before leaving the factory and reviewed during on-site joint debugging, and should not be left to the electrician's on-the-spot judgment. For example, a clean room needs to maintain positive pressure. If the fan stops after the signal is disconnected, the pressure difference in the room will quickly get out of control. At this time, it should be set to maintain a safe preset speed instead of shutting down. If the system has an upper limit for pressure difference, the speed should be reduced or stopped after the line is disconnected to prevent the pressure difference from being too high. These logics should be specified in the control scheme and set in the drive parameters. During debugging, signal disconnection should be simulated to verify whether the actual action meets the requirements.
Clean room ceiling air supply is comparableFFU fan filter unit ; centralized management of multiple devices can be matchedThe FFU computer group control system realizes zone speed regulation and status monitoring. Protection of single process equipment can be consideredEquipment-side fan filter unit (EFU) . The final filtered air supply at the end of the air duct can beHigh-efficiency air supply outlet (HEPA BOX) . The control interfaces and linkage logic of these devices and the DC fan chassis are different, and should be clearly specified on the system flow chart.
Control logic should be written as an executable document
Control logic cannot stop at verbal communication. It should be written as a control point table or logical description, including the following content:
Target air volume or pressure difference for each operating state
Corresponding speed range or control signal value
State switching conditions (time, sensor signal, manual command)
Speed control signal type and terminal definition
Fault feedback type (dry contact or communication)
Actions after disconnection
Interlocking relationship with dampers, fire protection or other equipment
This document should be delivered as part of the customized solution together with the equipment and electrical diagrams. During on-site debugging, verify the control actions according to the same document to avoid the situation of 'it is written on the drawing but not implemented in practice'.
Motor and control delivered together for verification
Aili Industry can discuss the combination of motors, fans, boxes and control supporting capabilities.DC fan chassis customization solution . The delivery requirements should cover both design and on-duty working conditions, and verify the response after start and stop, speed regulation, alarm and disconnection.
Specific structure and configuration options can be found inIt is confirmed in the fan box product catalog that non-standard projects should provide equipment or machine room drawings, and then shape them based on the determined working points and on-site interfaces. The control logic is written into the plan, and the equipment can be successfully connected to the system after it arrives on site, instead of being temporarily modified on site.
