Gordon crane technician started TH crane trouble shooting this morning. The problem is found that there is no 115VAC power supply to energize  a main coil which is used to switch on 450V AC power supply to crane. He did a test and found  the crane could be operated  by big yellow pedant in control room when he manually gave the coil 115VAC power supply to energize it.. At that moment, the crane is set to big yellow pedant operating mode. But, he can not figure out why there is no 115VAC power to this coil.The wiring  tracking back is not an easy job for him. The troubleshooting is  stopped now. The job will be resumed on next week with more skilled technician involving in from Gordon crane.