Direct answer: Barrier arm length is determined by the passage width to be closed; standard single-piece arms typically range from 3-6 meters. For wider openings (6 meters and above), a support post is added to the arm, a fenced (caged) arm model is used, or two barriers are positioned facing each other.
Why does arm length matter?
The longer the arm, the more torque the motor needs to overcome when lifting it. A motor working with an arm beyond its capacity wears out over time, opening time lengthens, and the risk of failure rises. That's why arm length should be evaluated together with motor power as a whole, not in isolation.
Solutions for wide openings
For passages exceeding 6 meters, three common solutions apply: adding a geared support post to the arm (prevents sagging), using a fenced/caged-boom barrier (both closes the wide opening and blocks passage underneath), or mounting two barriers facing each other, each covering half the opening. The choice depends on the site's width and budget.
Arm material and visibility
Arms are usually made from an aluminum profile; red-white reflective tape or an LED strip improves nighttime visibility. At entrances with pedestrian traffic as well, adding a cage to the lower part of the arm — or making the whole arm a caged design — physically prevents pedestrians from passing underneath.
Quick facts table
| Standard single arm | 3-6 meters |
|---|---|
| Opening over 6 meters | Supported arm, fenced-arm model, or dual barrier |
| Main risk | Arm beyond capacity → motor wear, slowdown |
| Pedestrian safety | Fenced/caged-arm models block passage underneath |
Frequently asked questions
How many meters can a barrier arm be?
Standard single-piece arms typically range from 3-6 meters; supported or fenced-arm models are preferred for wider openings.
Is a single arm sufficient for wide entrances?
As the arm gets longer, motor load increases; for very wide openings, a supported arm, fenced-boom barrier, or dual barrier arrangement is considered.
Last updated: July 20, 2026 · Technical content: Gray Teknoloji project team
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