Operation - Section 30 OM3070 Page 30-22 Operating Instructions GETTING OFF LINE As the truck approaches the end of the trolley line, it must exit the line properly. There will be signs or sig- nals near the end of the line indicating to the operator to exit the trolley lines. The operator must lower the pantograph which drops out the trolley, and the truck will go back to diesel. This is done by moving the master control lever rearward to the straight up, DIE- SEL position. This will start the drop out sequence.
LINE STATUS SIGNALS Line status signals are lights (much like traffic lights) that advise operators whether segments of trolley lines are energized and ready to accept haulage traf- fic. A different status signal light is used for each sec- tion of the trolley line that is energized. The lights are mounted to allow the driver to check the status of the line that the truck is approaching, so the pantograph can be lowered before that section of line is reached if the line is not able to accept haul- age trucks. Each ramp that is trolley equipped may have several different sections of energized trolley lines that make up the trolley line for the entire ramp.
Each section of line that is energized will have a sep- arate line status signal. NOTE: Following this procedure will cause the trolley power and the ready for trolley lights to turn off. The overhead cables taper upward as the truck approaches the end of the line. If the proper drop out sequence is not started the truck will drive out from under the cables with the pantograph still up. This will cause damage to the pantograph because of the arcing that will occur.
Since it is important that a driver lower the panto- graph before the truck reaches a de-energized sec- tion of ramp, the drivers must constantly monitor the line status signals and lower the pantograph if the line status signals indicate that an approaching sec- tion of line is not ready to accept haulage trucks. In the event an operator is required to get off of a trol- ley line to drive around an obstruction, such as rocks or disabled equipment, the operator will follow the procedure for getting off line, drive around the obsta- cle and follow the procedure for getting on line.
If an operator approaches a line status signal that is flashing red, indicating the line is not ready to accept haulage traffic, the driver will lower the pantograph before reaching that section of line. After proceeding past the section of line and the next line status signal indicates the next section of line is ready to accept haulage traffic, the operator will re-engage the trolley line as previously instructed and continue on trolley assist. DO NOT trolley assist lines unless the system has been de-energized and grounded by qualified electricians.
Only persons who have been properly trained and are qualified to perform the lock-out and grounding will be authorized to isolate the line or lines. Such authorization will be made in writing by the electrical engineering or electrical mainte- nance departments.