When do the generators turn on in the C-17 on the "AC X TIE" panel?

The C-17 aircraft checklist doesn't specify when to activate the 1st Gen, 2nd Gen, 3rd Gen, and 4th Gen generators on the "AC X TIE" panel.

Please help.

C-17 Checklists:

BOEING C-17 GLOBEMASTER III CHECKLIST NORMAL PROCEDURES

EXTERNAL PREFLIGHT SAFETY INSPECTION

Engine Covers - Removed
Pitot Covers - Removed
Wheel Pins - Removed
Wheel Chocks - Removed
Front Gear Tire Pressure - Check
Main Gear Tire Pressure - Check

PREFLIGHT SAFETY INSPECTION

Gear Handle - Down
ENGINE IGNITION NORM/ORIDE Switch - NORM
ENGINE IGNITION Selector Switch - OFF
ENG SHUT OFF Switches 1, 2, 3, 4 - OFF
GND OPS PWR Switch - OFF
BATT Switch - ON/Locked
DC X TIE Switch - AUTO
EMERG PWR Switch - AUTO
XFER BUSES Switch - NORM
L/R AV BUS Switches - AUTO
WAP (Warning/Caution Displays) - RESET MASTER CAUTION, Check WAP MSG
Fire Detection System - Tested
Smoke Detection System - Tested
EXT PWR Switch - ON if Available
AC X TIE Switch - AUTO
BAILOUT Alarm - TESTED
EMERG Lights - ARM
STALL Test - Complete, Verify WAP Messages and Sounds

PREFLIGHT CHECKLIST

Parking Brakes - ON
WAP (Warning/Caution Displays) - Checked
Interior/Exterior Lights - As Required
Cockpit and Instrument Illumination - As Required
IRU Switches 1, 2, 3, 4 - ON
HUD, MCD, MFDs - ON and Adjusted
COMM/NAV Radios - Set
Pilot STBY Instruments - Checked
ELT Switch - NORM
FED ARM Switch - Disarm
OBIGGS L&R Switchlights - ON
COMPT AIR FLOW - ON
TRIM AIR - ON
AVIONICS COOL ORIDE - OFF
W/S DEFOG - ON
L and R W/S Anti-Ice - OFF
ENG Anti-Ice - OFF
Probe Heat - OFF
No Smoking, Fasten Seatbelts Signs - ON
Anti-Skid/Brake Temp Switch - ARM
Mission Computer (FMC) - Initialized
FCS Actuator Panel - EFCS
Mission Computer Data / FMC - Setup Flight Plan and Verified
Fuel Pumps #3 - ON
APU Starter - START, wait RPM >95%
APU Bleed - ON
APU Generator - ON
HYD2 and HYD3 AUX Pumps - ON, verify PRESS PSI >3000

LOADMASTER CHECKLIST

Loadmaster Computer - On
Open Cargo Ramp/Door - As Required
Cargo Selected and Loaded - Check
Takeoff Weight is under Safe Limits - Verify
CG is under Safe Limits - Verify, crosscheck with Charts

BEFORE START ENGINES CHECKLIST

COMM Radios - Set
APU and External Equipment - As Required
Parking Brake - On
WAP Displays - Checked
Fuel QTY - Checked

ENGINE START CHECKLIST

MFD 2, 3 - Set for Engine Start
NAV Lights - ON
ANTICOL Lights - FSLG/WING
ENGINE IGNITION Selector Switch - A or B, or A&B
Throttles - IDLE
Bleed Air Supply - Checked
Engine Shutoff Valve 1 - ON
Start Engine 1 - Start
Monitor N2 and Engine Parameters, Engine 1 - Monitor
Engine Shutoff Valve 4 - ON
Start Engine 4 - Start
Monitor N2 and Engine Parameters, Engine 4 - Monitor
Start Engines 2, 3 - Follow Procedure Above, Start & Monitor
APU Bleed - OFF
Engine Bleeds - ON, All Four
Wing De-Ice - As Required
ENG Anti-Ice - As Required
Probe Heat Switchlights - As Required (ON Below 6 Deg C)
Packs L and R - ON
Hyd Pumps PRI/SEC/AUX - ON, All Four

BEFORE TAXI CHECKLIST

DC X TIE Switch - AUTO
Hydraulic XFER Pump - AUTO
Flaps/Slats - Checked for Full Movement
Flight Controls - Checked for Full Deflection
Flight Controls - Checked In MECH Law
APU Generator - OFF
APU - OFF
External Power - OFF
STBY ENG SEL - EPR
Thrust Rating - SET MAX, DRT or MAN as Required
Flaps - Set
Stabilizer, Rudder Trim, Aileron Trim - Set, 0 and 0
Altimeters - Set
Doors - Closed
Hydraulic Temps - Checked
WAP Display - Checked

TAXI CHECKLIST

Taxi - 40% N1 Max
Taxi Lights - On, Extended
Brakes - Minimize Use
Thrust Reversers - Avoid Repeated Cycle of use to Slow Down

BEFORE TAKEOFF CHECKLIST

Brakes, Steering and Stick - Checked
Flight Instruments - Checked
Probe Heat Switchlights - ON
Fuel Boost Pumps - ON
WAP Display - Checked

LINEUP CHECKLIST

Slats/Flaps - Extended, Flaps ½, Index Confirmed
Hydraulic Temps - Checked
Exterior Lights - As Required
Landing Lights - ON, Extended

TAKEOFF CHECKLIST

Brakes - Hold
Takeoff Thrust - MAX EPR or DRT EPR
Engines - Stabilize at 1.15 EPR
Brakes - Released
Rotate - 12 Degrees

AFTER TAKEOFF CHECKLIST

Landing Gear - UP, Lights Out
Flaps/Slats - UP/RET
Anti-Ice - As Required
Pressurization/Air Conditioning Packs - Checked and ON

CRUISE

Altimeters - Set
Anti-Ice - As Required
Pressurization - Checked
Exterior Lights - As Required
Pers Warning Signs - As Required

DESCENT

Engine Ignition Selector Switch - A or B or A&B
Anti-Ice - As Required
Pers Warning Signs - ON
Enroute Descent - Lowest of Mach 0.74 / 310 KIAS
Tactical Descent - Lowest of Mach 0.80 / 320 KIAS

APPROACH

Passing 10,000 - Feet 250 KIAS Max
Exterior Lights - ON
Altimeters - Set
Flaps - Set
Thrust Rating - As Required (Normally MAX)
WAP Display - Checked

BEFORE LANDING

Slats/Flaps - Extended, Flaps on Index
Landing Gear - Down
Spoiler Switch - ARM

LANDING

Normal Landing (3/4 to FULL Flaps) - FPV set to -1.0 TO -1.5 degrees, 240FPM
Assault Landing (FULL Flaps) - FPV set to -1.5 TO -2.0 degrees, 360 FPM
Reversers - Four REV, Reverse IDLE at 70 kts

AFTER LANDING

Flaps/Slats - UP/RET
Spoiler Switch - Dearmed
Exterior Lights - As Required
Cargo Door and Ramp - As Required
Engines - Operate at 1.05 EPR or less for 5 Minutes
Engine 1 and 4 HYD PRI, SEC, AUX Pumps - OFF
APU - Start
APU Generator - ON
Engine 1 and 4 Boost Pumps - OFF
Probe Heat - OFF

COCKPIT SWITCHOFF

Parking Brake - ON
Engine Shut Off Switches - OFF
Anti-Ice - OFF
Hyd Pumps - OFF
Interior and Exterior Lights - As Required
Pers Warning Signs - OFF
IRU Switches 1, 2, 3, 4 - OFF
OBIGGS L&R Swithlights - OFF
EMERG LT Switch - OFF
DC X TIE Switch - AUTO
EMERG PWR Switch - OFF
XFER Buses - OFF
APU - OFF
APU GEN - OFF
BATT Switch - OFF