TM 5-6115-329-14 TO  35C2-3-440-1 Section  IX.  Maintenance  of  the  Frame  Assembly 4-21.   Ground   Terminal WARNING Clean  all  parts  in  a  well-ventilated area.   Avoid   inhalation   of   solvent fumes   and   prolonged   exposure   of skin  to  cleaning  solvent.  Wash  ex- posed  skin  thoroughly.  Dry  clean- ing   solvent   (Fed.   Spec.   P-D-680) used   to   clean   parts   is   potentially dangerous   to   personnel   and   pro- perty.  Do  not  use  near  open  flame or   excessive   heat,   Flash   point   of solvent   is   100°   to   138°   F.   (38° to 59°  c.). a. Removal. To   remove   the   ground   terminal (figs.   1-1,1-3,   or   1-5),   remove   the   nut   and   lock- washer  and  remove  the  ground  terminal. b.  Cleaning. Clean   the   ground   terminal   and mounting   hardware   in   cleaning   solvent   Fed.   Spec. P-D-680,  and  dry  thoroughly. c. Inspect. Inspect   the   ground   terminal   and mounting   hardware   for   stripped   threads,   cracks, breaks,  burrs  or  other  damage. d.  Repair.   Replace   a   defective   ground   terminal. e. Installation.    Refer  to  figures  1-1,  1-3,  or  1-5 and   install   the   ground   terminal   with   lockwasher and  nut. f. Replace. For   fabrication   procedures,   see chapter   4,   section   X, Maintenance    of    Control Panel  Assembly,  paragraph  4-29. Section X. Maintenance of the Control Panel Assembly 4-22.   Rheosta t a.  Removal.   Refer  to  figures  4-21,  4-22,  or  4-23 and   the   following   instructions   and   remove   the rheostat. (1)  Tag  and  disconnect  leads  from  rheostat. (2)   Loosen   setscrew   securing   rheostat   knob on  shaft  and  remove  rheostat  knob. (3)   Remove   nut   securing   the   rheostat   to   the control   panel. (4)   Remove   rheostat. b.  Cleaning.   Clean  the  rheostat  with  a  clean  lint free  cloth. c. Inspection, Testing and Repair. Inspect   the rheostat   for   a   cracked   case,   for   evidence   of   over- heating   or   other   damage.   Inspect   knob   for   cracks or   breaks.   Ensure   rheostat   rotates   without   binding or   sticking.   Using   a   multimeter,   check   resistance across    outer    terminals    of    rheostat. Resistance should  be  approximately  5,000  ohms  for  the  MEP- 014A   and   MEP-019A   sets   and   500   ohms   for   the MEP-024A   sets.   Check   resistance   between   center terminal   and   outer   terminals   of   rheostat.   Full rotation   of   wiper   should   indicate   between   0 ohms    and    maximum    ohms    indicated    above. Replace  a  defective  rheostat. d.  Installation. (1)  Secure  rheostat  to  control  panel  with  nut. (2)  Place  rheostat  knob  over  end  of  shaft  and secure  by  tightening  setscrew. (3)   Reconnect   leads. 4-23 a. and Voltmeter WARNING Clean   all   parts   in   a   well-ventilated area. Avoid   inhalation   of   solvent fumes and prolonged exposure of skin to   cleaning   solvent. Wash exposed skin  thoroughly.  Dry  cleaning  solvent (Fed.   Spec.   P-D-680)   used   to   clean parts  is  potentially  dangerous  to  per- sonnel    and    property. Do   not   use near   open   flame   or   excessive   heat. Flash  point  of  solvent  is  100^o to  138° F.  (38°  to  59°  C.). Removal.   Refer  to  figures  4-21,4-22,  or  4-23 the   following   instructions   and   remove   the voltmeter. (1)  Tag  and  disconnect  leads  from  voltmeter. (2)   Remove   nuts, lockwashers   and   screws securing  the  voltmeter  to  the  control  panel. (3)   Remove   voltmeter. b. Cleaning. (1)  Clean   the   voltmeter cloth   dampened   in   cleaning P-D-680  and  dry  thoroughly. case   with   a   clean solvent   Fed.   Spec. (2)  Clean  glass  using  a  clean  cloth  and  a  mild soap  and  water  solution. c. Inspection. Testing  and  Repair. Inspect glass   for   discoloration,   chips,   cracks   or   scratches. Inspect   dial   face   for   legibility.   Inspect   voltmeter 4 - 4 0 Change  2