what crane device limits the angle of the boom at its highest position?

The crane device that limits the angle of the boom at its highest position is the boom stop (often implemented as a boom angle limiter or limit switch).

Quick Scoop: What it does

• The boom stop/boom angle limiter prevents the operator from raising the boom beyond a preset safe maximum angle.

• When that angle is reached, the device either stops further “boom up” motion or triggers an alarm and automatically cuts out the boom‑up function.

• This protects against tipping, boom structural damage, and overload conditions when the boom is too steep.

How it works (in simple terms)

• A sensor or limit switch monitors the boom angle continuously.

• As the boom approaches the maximum allowed angle, an early warning (alarm) is usually given a few degrees before the true limit.

• At the limit, the control system blocks any further upward motion while still allowing safe movements like lowering the boom.

Related terminology you might see

• Boom stop (common training/quiz answer to “what limits the angle at its highest position?”).

• Boom angle limiter / boom angle limit switch (technical description for the same function).

• Part of the Load Moment Indicator (LMI) or luffing limit device on some cranes, where boom angle is monitored and restricted as part of an integrated safety system.

TL;DR:
The device that limits the boom at its highest position is the boom stop (boom angle limiter/limit switch), which automatically prevents the boom from being raised past a safe maximum angle.

Information gathered from public forums or data available on the internet and portrayed here.