TM 5-6115-365-15 (10) Connect the load cables from the distribution   box   to   the   generator   sets   as   shown   in figure  22-4.    Attach  the  cables  to  the  floor  of  the  trailer with  the  clamps  provided.    Connect  the  out-going  load cables to the distribution box load terminals. c. Grounding. WARNING Never  operate  the  generator  set  until it has been properly grounded. Electrical  defects  in  the  load  lines  or equipment    could    cause    death    by electrocution. (1) The ground may be any of three methods, depending on the location and the terrain. (a) A  ground  rod  driven  to  a  depth  of  8 feet. (b) An underground metallic water piping system. (c) A  metal  plate  (9  square  ft)  buried  to a depth of four feet. (2) The   ground   lead   must   be   no.      6   AWG copper wire bolted or clamped to the rod, plate, or piping system. (3) Connect  the  other  end  of  the  ground  lead to the ground stud on the distribution box support. 22-4.  Starting WARNING Never operate the generator set in an enclosed  area  unless  exhaust  gases are    piped    outside.        Inhalation    of exhaust  fumes  may  result  in  serious illness or death. a. Perform the pre-starting operations in TM 5-6115-271-14. b. Position    the    transfer    switch    to    the    desired generator. c. Start the generator as described in TM 5-6115-271-14. 22-5.  Stopping Stop the generator set as described in TM 5-6115-271-14. 22-6.  Operation Operate the generator set as instructed in TM  5-6115-271-14.    Use  fuel  from  the  trailer-mounted fuel  tank.    When  refueling  tank,  operate  the  engine  with fuel  from  the  generator  set  fuel  tank  until  sediment  has had  a  chance  to  settle  in  the  trailer  fuel  tank.    Use  the fuel  transfer  valve  to  perform  fuel  transfer  operations. The  load  transfer  switch  on  the  distribution  box  is  used to  transfer  the  electrical  load  from  one  generator  to  the other (Fig. 22-5). Section III.  OPERATOR'S MAINTENANCE INSTRUCTIONS Operator's  maintenance  of  the  power  unit  is  concerned with  keeping  the  generator  sets  lubricated;  the  fuel  tank filled; and cleaning and servicing the fuel filters and   air   cleaners   as   described   in   TM   5-6115-271-14. Removal  of  dust  and  dirt  from  the  equipment  is  also  a routine maintenance function of the operator. Section IV.  ORGANIZATIONAL MAINTENANCE INSTRUCTIONS 22-7.  Fuel System Components a. General.  The fuel system consists of a fuel tank located  beneath  the  trailer;  the  generator  set  fuel  tanks located  beneath  the  generators,  on  the  skids;  and  the hoses  and  fittings  to  provide  fuel  to  the  engines.    A  fuel strainer in the filler neck is removable for cleaning.  The fuel level gage is located on the top of the tank near the filler neck. b. Fuel Tank Replacement. (1) Drain the fuel tank. (2) Loosen the hose clamps (45, Fig. 22-6) on the hose (44) to the filler neck at the tank. (3) Remove the nuts and washers that secure the  tank  hanger  to  the  bracket  and  lower  the  tank  far enough  to  disconnect  fuel  lines,  vent  hose,  and  ground wires on the top of the tank.  Remove the tank. Change 9  22-5