A crane operator assist device is any on-board computer used by the crane operator to manage the lift. Whether it’s called an LMI (load moment indicator), RCI (rate capacity indicator), RCL (rate capacity limiter), these computers show the crane operator the load radius, boom length, boom angle, and the load weight (not actual load weight, but load exerted on the crane). An LMI includes load charts sometimes for multiple cranes, and other times they are manufacturer specific and built into the crane. Advanced crane operator assist devices provide even further integration with the crane and include functions like boom torque, wind, ice, outrigger monitoring and more. You can also find anti two-block devices. These devices can either act as a warning device which activates an audible alarm, or as an anti two-block prevention system. An anti two-block prevention system will disable the functions of hoist up, extend boom, and lower boom. Boom angle limiting devices can also be found on Cranehunter.com. These devices will allow a crane operator to set high and low angle limits, which when reached will sound an audible alarm.. Find crane operator assist devices, LMI, and other crane computers on Cranehunter.com.