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i4500 LMI-RCI

LOAD MOMENT Indicators & RATED CAPACITY Indicators

Load moment indicators (LMI) and rated capacity indicators (RCI)  are the most essential operator aid for protecting your crane from an overload accident. Both systems monitor the essential information the crane operator needs to know. The crane LMI  or crane RCI  shows the operator the weight of the load being lifted, the capacity at that radius, the boom angle,  length, radius, and anti-two block (ATB) warning.


There are several different sensors and designs used to monitor this information. LMI systems measure the force on the boom. Usually, this is on a telescopic boom crane and done with pressure sensors on the rod and bore side of the boom lift cylinder. RCI systems directly measure the tension of the hoist line. Typically, this is done with a load link,  pin, or dynamometer.


Rayco/Wylie built the first crane overload indicator in  1934  and offers the latest technology and design for crane LMI  &  crane RCI  systems today. We supply LMI and RCI  systems for all types of cranes. The i4500 LMI / RCI is available for small carry deck cranes, large lattice cranes, tower cranes, offshore cranes, and everything in between. The i4500 comes in three screen sizes.  (4.3”, 7” and 10”). It uses a CANbus network for easy troubleshooting and diagnostics. Calibration data can be uploaded or downloaded by USB.  There is an optional data logger that can be used to record all the lifting activity. 

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