Deck Crane Ramp Time

In this post I’ll write and share some information about ramp time of a deck crane.

Set ramp time

The set time is refer to 100% command signal (stepped input signal).

Example: A ramp time of max 5 s may be set at 100% command signal. Additionally, if a command signal of 60% is set then the command signal is reached after approx. 3 s.

Deck Crane control

A feature that a deck cranes have is acceleration and retardation of speed winches as it is put into action.

The hydraulic deck crane comprise of tree circuits hoisting, luffing and also slewing circuits.

Furthermore to give a smooth acceleration and retardation of the winches and slewing machinery the control system is fitted with device that gives a special ramp time.

A crane control system comprise of a micro processor cards. One of this is use for internal communication and the other for controlling  all input and output signals for one crane movements. The crane joystick direction trough the potentiometer signal goes to a microprocessor. This handles brake release logic, overload logic and ramp time.

Troubleshooter jobs, good and mad that you went through. Have A Great Story About it? Have fun, write and share them here.

Therefore when hoist a load and joystick of the crane is move in that direction, speed of hoisting winch increase from zero to max speed. To protect the structure and crane components a smooth acceleration to the winch movement is obtain. It’s the time it takes to increase the winch speed from standstill to maximum speed when control lever is move rapidity to desired direction.

Hoisting/Lowering

The same way also takes for deceleration to decrease the speed from maximum speed to standstill in case the joystick is drop. The hoisting system ramp time varies among different cranes, and the ship cranes I work with have a set 2 sec. 

Furthermore other crane movements luffing, slewing the set ramp time at first is 2 sec and second for 4 sec.

Have a comment about this topic! Share it here!