Size of air switch in distribution box

Air switches in distribution boxes vary by type, but typical dimensions for Eaton Type ED switches are designed to accommodate 400–600 A current with mounting flexibility, while compact HVAC switch boxes range from 195 mm to 250 mm in height.

Eaton Type ED Air Switch Dimensions

The Type ED air switch is a single-pole, enclosed air switch rated for 7.8 kV, 75 kV BIL, and 400–600 A continuous current. Its porcelain-housed design allows for vertical, angled, or pole mounting using a crossarm bracket. Terminals accommodate No. 4/0 through 500 MCM wire, and the switchblade provides a clear open/closed indication. The switch includes a quick-break mechanism for safe interruption of transformer magnetizing currents, and all live parts are protected by a closed-door design. Exact dimensions are provided in Eaton's catalog, but the switchblade hangs below the housing when open, ensuring positive visual confirmation of the switch status .

Compact HVAC Air Switch Boxes

For HVAC or VRF systems, compact air switch boxes such as Bosch AF-SB models have installation heights of 195 mm for the smallest model and 250 mm for larger models, with lightweight construction for easy mounting. These boxes can connect multiple indoor units (up to 8 per port) and include options for refrigerant leakage detection. The width and depth are designed to fit standard installation spaces while providing sufficient internal volume for wiring and connections .

Installation Considerations

• Mounting: Air switches can be mounted vertically, at an angle, or on poles depending on the model.
• Wire Capacity: Ensure the switch terminals match the conductor size (e.g., 4/0–500 MCM for Type ED).
• Clearance: Allow space for the switchblade movement and door operation.
• Enclosure Size: Distribution boxes must accommodate the switch dimensions plus wiring space, typically requiring deeper boxes for higher amperage switches . In summary, the physical size of an air switch depends on its type and application: industrial distribution switches like Eaton Type ED are larger and designed for high current, while compact HVAC switch boxes are smaller (195–250 mm height) for easier installation in limited spaces. Always consult the manufacturer's datasheet for precise dimensions and mounting requirements.