Fiber Optic Distribution Box Height Specifications

Fiber optic distribution boxes typically range from 200 mm to 600 mm in height, depending on capacity and mounting type.

Overview

Fiber distribution boxes (FDBs) are enclosures used to terminate, splice, and distribute optical fibers in FTTH, FTTB, and other optical networks . They can be wall-mounted, pole-mounted, or installed inside cabinets, and their height depends on the number of fiber ports, splice trays, and additional components like PLC splitters or slack storage .

Typical Heights

• Small indoor wall-mounted FDBs: Usually 200–300 mm tall, designed for low-density applications (8–24 fiber ports) and compact indoor spaces .
• Medium to large wall-mounted FDBs: Typically 300–500 mm tall, supporting 24–96 fiber ports with multiple splice trays and space for cable management .
• Outdoor or cabinet-style FDBs: Can reach up to 600 mm or more, especially for high-density deployments (up to 288 fibers) and additional environmental protection .

Additional Considerations

• Depth and width: Usually range from 100–250 mm in depth and 200–500 mm in width, depending on fiber capacity and mounting requirements .
• Mounting: Wall-mounted boxes often have 4-point mounting holes and twin doors for easy access, while larger cabinets may include pole or pedestal mounting .
• Material and protection: Indoor FDBs are often made of ABS or ABS+PC, while outdoor boxes use SMC or high-impact plastics with IP65 or higher ratings for weather resistance .

Summary

For most indoor FTTH or FTTB deployments, a wall-mounted fiber distribution box will typically be 200–500 mm in height, with smaller boxes for individual apartments and larger boxes for multi-unit buildings. Outdoor or high-capacity cabinets can exceed 600 mm to accommodate more fibers and environmental protection. Proper selection ensures efficient fiber management, future expansion, and ease of maintenance .