CTRLIM is a moment limiter for cranes. The moment limiter stops the crane when the moment on its boom is higher than a preset value.
Moment is calculated by an angle sensor, a boom length sensor and a hydraulic pressure on the boom main cylinder.
A moment limiter enhances the safety of cranes, because it stops the crane movement before it becomes dangerous. When a crane lifts a load, it can be safe for some angles, but not safe for other angles or if boom length is too long. As you can see in the example in the right, when boom is longer, it is possible to lift a lighter load. When the boom is in horizontal position, it is possible to lift a lighter load.
CTRLIM moment limiter, the project.
Electronic board, design of schematic and printed circuit layout of the moment limiter with following specifications:
- central microprocessor;
- analog power supply stage;
- RS232 port to communicate to PC and setup;
- N. 2 analog inputs for pressure sensors (4-20mA);
- N. 1 analog input for angle sensor (0-5V);
- N. 1 analog input for boom length sensor (0-5V);
- digital outputs to stop the equipment;
- digital output for light/sound signal;
- status LEDs.
Programming languages: Assembler, GWbasic.
Project started on: May, 1994. Status: out of production.