TM 1-1510-225-10 8-10 a.  EFIS POWER switches – OFF. b.  AP/TRIM POWER switch – OFF. c.   CABIN PRESS switch – PRESS. d.  RUDDER BOOST switch – On. e.  Pressurization controller – Set. * 9.  Copilot's instrument panel – Set. Compass control – SLV. 10.  Copilot's clock – Check and set. * 11.  Copilot's subpanel – Check. a.  CABIN signs – As required. b.  VENT BLOWER switch – As required. c.   AFT BLOWER – OFF. d.  BLEED AIR VALVES switches – ENVIR OFF. e.  CABIN TEMP MODE control – OFF. f.    CABIN/COCKPIT AIR control – OFF. g.  COPILOT AIR control – As required. h.  MIC selector switch – NORMAL. i.    Oxygen pressure – Check. * 12.  Copilot's circuit breaker panel – Check. 13.  Static air source – Normal. * 14.  BATT  –  ON  (23  volts  minimum  for  battery start). 15.  Overhead panel lights – As required. 16.  Exterior lights – As required. CAUTION Never connect an external power source to the  aircraft  unless  a  battery  indicating  a charge of at least 20 volts is in the aircraft and   in   the   ON   position.      If   the   battery voltage  is  less  than  20  volts,  the  battery must   be   recharged,   or   replaced   with   a battery  indicating  at  least  20  volts  before connecting  external  power.    Use  only  an external  power  source  fitted  with  an  AN- type plug. 17.  GPU – As required. 18.  External power advisory light – As required. 19.  DC volt/loadmeters – Check loads, voltage, and current limiters. When an external power source is used, it must be set as follows: 28.0 to 28.4 volts 1000 amps capacity 300 amps maximum continuous NOTE If  the  battery  is  partially  discharged,  the BATTERY  CHG  annunciator  will  illuminate approximately    6 seconds    after    external power  is  on  line.    If  the  annunciator  does not  extinguish  within  5 minutes,  refer  to the   Battery   Chg   Annunciator   Illuminated procedure in Chapter 9. The  battery  should  be  on  to  absorb  transients present in some auxiliary power units.  An  EXT PWR annunciator  alerts  the  crew  when  an  external  power plug is connected to the aircraft. * 8-22.  FIRST ENGINE START (BATTERY START). NOTE After turning on the BATT SWITCH, wait a full 10 seconds before starting the engines to  allow  the  ETM  to  complete  its   setup procedures. Starting    procedures    are    identical    for    both engines except the second engine generator is kept off line after the second engine  start  to  allow  performing the  current  limiters  check.    When  making  a  battery start,   the   right   engine   should   be   started   first.      A crewmember   should   monitor   the   outside   observer throughout the engine start. 1.  Propeller area – Clear. 2.  Engine – Start. a.  IGNITION AND ENGINE START switch – ON.        IGN    ON    annunciator    should illuminate  and  associated  FUEL  PRESS annunciator should extinguish.