+966 57 849 0480
Make a Call
info@safetechco.com
Drop us a Line
Make a Call
Drop us a Line
The SafeTech Crawler Crane LMI is an advanced Load Moment Indicator (LMI), Safe Load Indicator (SLI), and Rated Capacity Indicator (RCI) system designed for lattice boom crawler cranes.
The system continuously monitors critical crane parameters, including load, working radius, boom angle, crane configuration, Anti-Two-Block (A2B) status, and optional wind speed. It processes this information against the applicable manufacturer’s rated-capacity and load-chart data to provide the operator with clear, real-time information about the crane’s lifting condition.
When the crane approaches a configured safety limit, SafeTech LMI provides visual and audible warnings. Where supported by the crane’s control system, the LMI can also provide configurable movement limitation or lockout protection for selected unsafe movements.
A Crawler Crane Load Moment Indicator (LMI) is an electronic safety system that monitors load weight, working radius, boom angle, and crane geometry in real time. By continuously comparing live measurements against pre-programmed duty charts, the LMI alerts operators before an overload or tipping condition occurs.
SafeTech Crawler Crane LMI provides real-time operating information and visual/audible warnings when configured limits are approached, with optional Anti-Two-Block (A2B), wind monitoring, and movement protection depending on the crane configuration and control-system interface.
When searching for a crawler crane LMI system, you may also encounter the terms SLI (Safe Load Indicator) and RCI (Rated Capacity Indicator).
These terms can vary depending on the crane manufacturer, region, and technical documentation, but they generally refer to crane systems that monitor lifting conditions and rated capacity.
| Feature | LMI (Load Moment Indicator) | RCI (Rated Capacity Indicator) | SLI (Safe Load Indicator) |
|---|---|---|---|
| Full Name | Load Moment Indicator | Rated Capacity Indicator | Safe Load Indicator |
| Primary Focus | Geometric configuration & tipping moment | Load-chart percentage comparison | Operator warning & motion cutout |
| Primary Variables | Load, working radius, boom angle, boom length | Hook load, duty chart limits, reeving | Safe load threshold vs. current load |
| Typical Application | Crawler cranes, lattice boom cranes, mobile cranes | Telescopic cranes, all-terrain cranes, fixed-chart cranes | General mobile cranes, legacy installations |
For lattice boom crawler cranes, LMI is a widely recognised term for crane load and capacity monitoring.
SafeTech Crawler Crane LMI provides real-time monitoring of load, working radius, boom angle, crane configuration, Anti-Two-Block (A2B), and optional wind speed, with configurable warnings and protection functions based on the specific crane installation.
SafeTech LMI relies on a network of high-precision sensors linked to a central processing unit and an in-cab operator interface:
| Component / Sensor | Installation Location | Operational Role & Primary Function |
|---|---|---|
| Load Sensor (Rope Clamp / Load Cell) | Wire-rope dead end / load point | Measures line tension and suspended load forces to compute actual hook weight. |
| Boom Angle Sensor (Inclinometer) | Boom base / lower boom section | Continuously measures lattice boom angle to compute dynamic working radius. |
| Anti-Two-Block (A2B) Switch | Boom head / tip assembly | Detects an approaching two-block condition to trigger alarms and hoist cutouts. |
| Central Processing Unit (CPU) | Protected cab junction enclosure | Evaluates real-time sensor data against stored duty charts and reeving parameters. |
| In-Cab Interface Display | Operator cab console | Ruggedized screen providing live load metrics, capacity bars, and audible alarms. |
| Wind Speed Sensor (Anemometer) | Boom tip / elevated location | Optional. Monitors ambient wind velocity during long-boom or high-risk lifts. |
| Jib Angle Sensor | Jib assembly (where equipped) | Tracks secondary jib offset angle relative to the main lattice boom. |
SafeTech Crawler Crane LMI provides a configurable warning sequence as the crane approaches its rated operating limit.
Displays exact hook weight, lifting distance, boom angle, and safe weight percentage on screen in real time.
Loud alarms and clear colour screens guide crane operators during difficult or hidden lifts.
Prevents crane tipping, boom damage, and machine stress by stopping lifts that are too heavy.
Fully meets Saudi Aramco GI, SABIC, and international safety rules for fast site approval.
Instantly stops dangerous upward moves when the load reaches $100\%$, but lets the operator safely lower the load.
Saves lift history and system reports to make safety checks and daily maintenance easy.
Crawler crane LMIs are subject to regular inspection, testing, and calibration to ensure load readings are accurate and meet rigorous site safety audits, including Saudi Aramco GI, SABIC, and ASME B30.5 standards. SafeTech offers fast on-site field support in Jubail, Dammam, Yanbu, Riyadh, and NEOM for complete LMI installation, configuration, multi-point calibration, testing, and site commissioning.
Live numeric and percentage comparison of current load against maximum permitted load.
Real-time distance calculation from the crane's center of rotation to the hook center.
Continuous readout of active boom length, boom angle, and jib offset angle.
A color-coded bar graph (green / yellow / red) providing instant visual feedback on structural capacity limits.
The rugged in-cab interface translates real-time sensor measurements into clear operational data:
Visual verification of sensors, cables, display power, and A2B switches.
Testing screen readouts, warning sirens, and hydraulic motion cutouts.
Zeroing sensors and running multi-point test lifts with certified weights.
Re-checking settings whenever boom length, jib, reeving, or counterweights change.
SafeTech supports LMI installation, configuration, calibration, testing, and commissioning for crawler cranes.
🟢 Green (Normal Condition): Normal operating condition. Continue operation within rated capacity limits.
🟡 Yellow (Pre-Warning): Configured warning limit approaching (85% to 99%). Reassess the lift and avoid increasing the working radius.
🔴 Red (Critical Alarm): Critical limit reached or exceeded (greater than or equal to 100%). Stop affected movement immediately and follow the safe lowering procedure.
⚠️ A2B Alarm: Anti-Two-Block condition detected. Stop hoisting movement immediately and lower the block to clear the switch.
💨 High Wind Alert: Configured wind-speed limit reached. Follow crane manufacturer and site wind-operating requirements.
🔧 System Fault: Sensor, communication, or calibration fault. Stop operation and inspect wiring and sensor diagnostics.
