How to Size a VFD Cabinet for Your Motor Drive

Cooling, ventilation, and sizing considerations for VFD panels.

Sizing a VFD (Variable Frequency Drive) cabinet is more than putting the drive in a box

Key considerations

1. Heat dissipation: VFDs generate heat (2-3% of power). A 100kW drive generates 2-3kW of heat, so size the cooling accordingly: exhaust fan for small drives, air conditioner for large ones.
2. Ventilation: filtered intake and exhaust, not sealed (unless washdown).
3. EMC: VFDs emit electromagnetic noise. Use shielded cables, EMC filters and a separate control compartment.
4. Braking: if the motor brakes frequently, add a braking resistor in a separate compartment.
5. Access: front door for the keypad, rear door for servicing.
6. Cable entry: power in at the bottom, control on the side.

At Yiguangnian, we size VFD cabinets based on your drive model and application, with proper cooling and EMC design.