3CTR is a complete electronic control system for tunneling lifting equipment. It is installed on 3 booms lifting equipments for tunneling: 2 platforms to lift people and 1 central boom used to lift centres in tunnels.


Electronic proportional manipulators complete each platform transmitter: these components are useful to make movements very accurate. Each manipulator is provided with consent pushbuttons, helpful to avoid that an accidental manipulator movement would compromise operators’ safety.

Boom laying centres controls reunite in only two manipulators every function necessary for centre laying. Two separated pushbuttons command clamps opening and closing, to avoid accidental centre unlocking.

There is an emergency pushbutton, important to block the whole equipment in case of emergency. 3CTR electronic control system for tunneling lifting equipment is equipped with an useful function that inhibits mechanical movements in hazardous conditions. Electronic movement and load limiter (a microprocessor based device) helps operators to lift a centre in safe conditions.
Stabilization controller assures that the lifting equipment is perfectly stabilized to the soil before beginning a working session and a centre mounting.

Moreover commands selector avoids simultaneous incompatible movements, allowing the operator to concentrate on the movement he’s making.

3CTR electronic control system for tunneling lifting equipment, the project.
3CTR is a huge project, because it is composed by 16 different PCB electronic boards, more than 40 ICs and more than 550 discrete electronic components. All functions are performed by logic ICs, while the moment and area limiter (a safety device) is equipped with a microprocessor, completely programmed in Assembler language (this is an embedded version of CTR LIM standalone version). 3CTR electronic control system for tunneling lifting equipment commands more than 40 solenoid valves (on/off and proportional).

3CTR electronic control system for tunneling lifting equipment, electronic boards list.
3CTR R, relay main board

3CTR RDX, mainboard and PCB rack


3CTR RSX, mainboard and PCB rack

3CTR ALIM, filtered power supply

3CTR STAB, lifter stabilization process

3CTR SEL, command transmitter selector


3CTR DEC, command decoder

3CTR ALL, centre widener manager

3CTR LIM, moment and area limiter

3CTR TC,command transmitter

3CTR TX1, command transmitter 3CTR TX2, command transmitter


3CTR EBK, safety board for booms lifting peoples

3CTR EBF, boom solenoid valves buffer

3CTR CEST, proportional solenoid valves processor

3CTR TM, work hours calculator

Party with “decorated” tunnel lifting equipment.

Project started on: Oct, 1996. Status: out of production.
