corrigendum - operation and maintenance of essential services of newly constructed nidem building at ulaan batar marg , delhi cantt . , deploying of one supervisor ( electrical diploma holder / degree ) to supervise all the electrical installation such as internal electrification / sub station , generator set , floor panels and hvac and vrf installations , auditorium stage lighting and sound system etc . in the general shift from 9 am to 5 . 30 pm , electricians ( two ) to maintain & operate the internal electrification emergency and normals , fixtures , switch socket , plugs etc . . to maintain & operate the 11 kv sub station consisting of ht panels , transformer , lt panels and gen set , hvac , vrf system , auditorium lighting and sound system , pump , curtains etc in general shift or as required . , plumbers ( one ) in general shift of 8 hrs to attend the fault / leakage in the pipe line , pumps , bath fittings and other water supply installations , a . c . mechanic ( one ) for service and repair to ac plants , vrf cassette etc . , carpenter ( one ) for repair to the door , window and other wooden works etc . , gen . technician ( one ) to maintain operate electrical , water supply installation sound system etc . , helpers ( three ) to assist electrician , plumber , carpenter and ac machine technician so that one helper remain with technician to maintain and operate installations .