TM 1-1510-218-10 9-12 2.   BATT switch – OFF (monitor loadmeter). IF LOADMETER STILL INDICATES ABOVE 100%: 3.   Nonessential electrical equipment – off. IF LOADMETER INDICATES 100% OR BELOW: 4.   BATT switch – ON. d.  INVERTER Light Illuminated.  Illumination of the  #1 or  #2 INVERTER caution light  indicates failure of the affected inverter.  When either inverter fails, the total ac load is automatically switched to the remaining inverter.  When a #1 or #2 INVERTER light illuminates, perform the following: 1.   Affected INVERTER switch – OFF. e.   INST  AC  Light  Illuminated.    Illumination  of the  INST  AC  warning light indicates  that  both  26-Vac transformer   circuits   are   inoperative.      The    primary power-indicating instruments, torque, and fuel flow will be  inoperative.    Under  these  conditions,  power  must be controlled by indications of the N₁ and TGT gauges. Perform the following: 1.   N₁ and TGT indications – Check. 2.   Other engine instruments – Monitor. f.    Circuit   Breaker   Tripped.        If    the    circuit breaker is for a nonessential item, do not reset in flight. If the circuit breaker is for an essential item, the circuit breaker  may  be  reset  once.    If  a  bus  feeder  circuit breaker (on the overhead circuit breaker panel) trips, a short  is  indicated.    Do  not  reset  in  flight.    If  a  circuit breaker trips, perform the following: 1.   BUS  FEEDER  breaker  tripped  –  Do  not reset. 2.   Nonessential circuit – Do not reset. 3.   Essential circuit – Reset once. NOTE Circuit  breakers  should  not  be  reset  more than     once     until     the     cause     of     circuit malfunction    has    been    determined     and corrected.      Do   not   reset    dual-fed    bus feeder circuit breakers. g.  BATTERY  CHARGE  Light  Illuminated.    If the    BATTERY   CHARGE    caution    light    illuminates during normal flight, perform the following procedure. 1.   Loadmeter – Check and note indication. 2.   BATT switch – OFF. 3.   Loadmeter – Check. If loadmeter indicates    less   than   2.5%   change    (one needle  width),  turn  BATT  switch  ON  and monitor    for    increasing    load.        If    load continues  to  increase,  turn  BATT  switch OFF. NOTE The  battery  may  be  turned  back  ON  only for  gear  and  flap  extension  and  approach to  landing.    Battery  may  be  usable  after  a 15 to 20-minute cool down period. 4.   BATT  switch  (landing  gear/flap  extension only) – ON. h.  AVIONICS MASTER POWER Switch Failure.    If  the  AVIONICS  MASTER  POWER  switch fails    to    operate    in    the    ON    position,    perform    the following procedure. NOTE The  avionics  power  relay  is  normally  hot. Pulling   the    AVIONICS   MASTER   CONTR circuit  breaker  will  remove  power  to  the relay, thus allowing electrical power to the associated buses. 1.   AVIONICS MASTER CONTR circuit breaker – Pull. 9-29.  EMERGENCY DESCENT. Emergency descent is a maximum effort in which damage to the aircraft must be considered secondary to  getting  the  aircraft  down.    The  following  procedure assumes   the   structural   integrity   of   the   aircraft   and smooth  flight  conditions.     If  structural   integrity   is   in doubt, limit speed as much as possible, reduce rate of descent   if   necessary,   and   avoid   high   maneuvering loads.  For emergency descent, perform the following: 1.   POWER levers – IDLE. 2.   PROP levers – HIGH RPM. 3.   FLAPS – APPROACH. 4.   GEAR – DN. 5.   Airspeed – 181 KIAS maximum.