Moving speed for ground control of overhead crane has two kinds: 20m/min and 30m/min, CD1 model electric hoist moving speed: 20m/min and 30m/min, 
lifting speed 8m/min
Electrical devices for CD1 model electric hoist include electric control box, control button and fire cutoff stopper. As operating the machine on the ground,
the operator must firstly start total startup button, make general contactor closed, then all systems can begin running. Start running buttons of all systems,
contactor closes, then motor immediately moves forward or backward. To start crane moving system smoothly, connect a resistance in the motor stator,
then immediately make a short circuit by time relay delay closed contact after finishing starting the crane (setting time 4-6s). When crane moves to the
limit position, a pair of contacts of travel switch are opened, the system power is interrupted, so the system can only be controlled to move backward.