Wegner Crane CFW500 series Applications Manual - page 17
Crane
Crane | 17
2 CRANE
2.1 VERTICAL MOTION
The crane vertical motion consists in moving a load vertically, executing commands for hoisting and lowering
together with the mechanical brake control, which must assure that the load remains in the intended position
when no hoisting or lowering commands exist.
The crane vertical motion control developed for the CFW500 SoftPLC presents the following characteristics:
■
Speed reference selection through electronic potentiometer (EP), logical combination of digital inputs
(maximum of 5 references), analog input (step less) or communication networks;
■
Commands for load hoisting and load lowering through digital inputs or through communication networks;
■
Option of inverting the motor rotation direction adopted as standard for load hoisting and load lowering;
■
Linear or “S” curve acceleration and deceleration ramps for crane vertical motion;
■
Option of stopping command via digital input, which can be for coast to stop, fast stop or emergency stop
with deceleration ramp;
■
Minimum and maximum speed limits for crane vertical motion;
■
Gain, offset and filter settings for control speed signal through analog input;
■
Mechanical brake release logic controlled by motor frequency and/or motor current and/or motor torque, with
independent settings for load hoisting and load lowering commands;
■
Adjust of the brake response time to release avoids the increase of the motor frequency;
■
Mechanical brake closing logic controlled only by motor frequency (total speed reference in Hz);
■
Possibility of brake closing delay time;
■
Adjust of the time to enable a new command to brake release after the command to brake closing preventing
a new command to be generated without the brake being mechanically closed;
■
Possibility of brake inhibition during the transition from hoisting to lowering and vice-versa (only with encoder);
■
Digital inputs programmed for limit switches (over travel limits) functions to reduce the speed (slowdown) while
hoisting;
■
Lightweight detection while hoisting or lowering the load;
■
Overweight detection while hoisting the load, with subsequent alarm;
■
Slack cable detection while lowering the load, with subsequent alarm or fault;
■
Inverter in torque limitation detection while hoisting or lowering the load, with subsequent fault;
■
Fault trip by improper use of the crane vertical motion;
■
Crane vertical motion alarm (the last three) history;
■
Possibility of applicative implementation or modification by the user through the WLP software.