HV CONTROL CUBICLE FOR NON-AC COACHES

The HV cubicle which is installed under slung of the LHB coach which is given by main feeder lines of 750V AC 3ɸ. The two lines are connected directly to disconnecting and earthing device. Then the line passes through the main fuses of 25A and measuring and monitoring relays. These relays are designed to detect overloads, temperature, liquid and other potentially damaging fluctuations. After the main fuses, lines are fed to the main contactors K01 & K02. When MMR relays are OK and no tripping conditions occur, by the selection of either one of the NET supplies one of the contactors pass this supply. Two contactors never work at the same time. For this operation sufficient interlocking is made in the HV panel. Then the 750 V 3ɸ Supply is fed to the 15/9 KVA Transformer 750/415 &190V star –star connected transformers and after step down the supply given back to the HV cubicle. The main function of the disconnecting and earthing device is to separate the two feeders (input supply) and simultaneously earthing 750volts AC network of the coach. The connection to the device can be made by removing the top cover on the front of the device. The panel consist of switchgear for main contactors, measuring and monitoring relays, contactors for pump control, MPCB, mounting for pump controller and cage clamp terminal.The rotary switch for the feeder selection is provided on the panel to select the feeder as provided in the under slung HV cubicle. The control for the feeder selection contactors is on 110V DC only.