TM  55-1510-221-10 Table  2-7.  Caution/Advisory  Annunciator  Panel  Legend (Sheet 2 of 2) CAUTION/ADVISORY  ANNUNCIATOR NOMENCLATURE COLOR CAUSE  FOR  ILLUMINATION L  BL  AIR  IFF Green Left  environmental  bleed  air  valve  closed EXTERNAL   POWER Green External  power  connector  plugged  in R  BL  AIR  OFF Green Right  environmental  bleed  air  valve  closed No.2  IGN  ON Green No.2  engine  ignition/start  switch  on,  No.2  engine  autoignition switch  armed  and  engine  torque  below  20  percent No. 1 AUTOFEATHER Green No.1   engine   autofeather   armed   with   power   levers   advanced above 90% N₁ No.2  AUTOFEATHER  Green No.2   engine   autofeather   armed   with   power   levers   advanced above 90% N₁ BRAKE  DEICE  ON Green Brake  deice  system  activated a.   Annunciator   Panels.   Three   annunciator panels  are  installed.  One  is  a  warning  panel  with  red fault  identification  lights,  and  the  others  are  caution/ advisory  panels  with  yellow  and  green  identification lights.  The  warning  panel  is  mounted  near  the  center of   the   instrument   panel   below   the   glareshield   (fig. 2-29)  and  one  caution/advisory  panel  is  located  on the  center  subpanel  (fig.  2-6).  The  mission  annuncia- tor  panel  is  located  on  the  copilot’s  sidewall.  Some normal   flight   operations   involve   indications   from the   mission   control   panel   (fig.   4-l).   Illumination   of a  red  warning  light  signifies  the  existence  of  a  haz- ardous  condition  requiring  immediate  corrective action.  A  yellow  caution  light  signifies  a  condition other   than   hazardous   requiring   pilot   attention.   A green  advisory  light  indicates  a  functional  situation. Table  2-6,  2-7,  and  2-8  provides  a  list  of  causes  for illumination  of  the  individual  annunciator  lights.  In frontal   view   both   panels   present   rows   of   small, opaque   rectangular   indicator   lights.   Word   printing on  each  indicator  identifies  the  monitored  function, situation,   or   fault   condition,   but   cannot   be   read until  the  light  is  illuminated.  The  bulbs  of  all  annun- ciator   panel   lights   are   tested   by   activating   the ANNUNCIATOR  TEST  switch,  located  on  the  right subpanel   near   the   caution/advisory   panel.   The   sys- tem   is   protected   by   two   5-ampere   circuit   breakers placarded  ANN  PWR  and  ANN  IND  on  the  over- head  circuit  breaker  panel  (fig.  2-26).  The  annuncia- tor   system   lights   are   dimmed   when   the   MASTER PANEL  LIGHTS  switch  is  ON  and  the  pilot’s  flight instrument   lights   are   illuminated.   The   lights   are automatically  reset  to  maximum  brightness  if: (1.)  The   main   aircraft   power   (both   DC generators)  are  OFF. (2.)  T h e   I N S T   I N D I R E C T   L I G H TS switch  is  rotated  clockwise. (3.)  The   MASTER   PANEL   LIGHTS switch  is  off. (4.)  The   MASTER   PANEL   LIGHTS switch  is  ON  and  the  PILOT  INST  LIGHTS  switch is  OFF. (5.)  Master  warning  light  (red).  A  MAS- TER  WARNING  light  is  provided  for  both  the  pilot and  the  copilot  and  is  located  on  each  side  of  the glareshield  (fig.  2-29).  Any  time  a  warning  light  illu- minates,  the  MASTER  WARNING  light  will  illumi- nate,   and   will   stay   illuminated   until   the   MASTER WARNING  light  is  pressed  to  reset  the  circuit.  If  a new  condition  occurs,  the  light  will  be  reactivated, and  the  applicable  annunciator  panel  light  will  illu- minate. (6.) Master caution light (yellow). A MAS- TER  CAUTION  light  is  provided  for  both  the  pilot and  copilot  located  adjacent  to  the  MASTER WARNING  LIGHT.  Whenever  a  caution  light  illu- minates,   the   MASTER   CAUTION   will   illuminate, and  will  stay  illuminated  until  the  condition  is  cor- rected  and/or  the  MASTER  CAUTION  light  is pressed  to  reset  the  circuit.  If  a  new  condition occurs,  the  light  will  be  reactivated  and  the  appro- priate  annunciator  panel  lights  will  illuminate. b. Clocks.  One  manually-wound  8-day  clock  is mounted  in  the  center  of  the  pilot’s  control  wheel and  an  electric  digital  clock  is  mounted  in  the  center of  the  copilot’s  control  wheel. 2-76