TI4400 GPU-24
18
3
Operating Procedures
Removing DC Power Supply From Vehicle
1. Remove dc power cable GPU connector from vehicle.
2. Remove dc power cable connector from TI4400 GPU-24 (if necessary).
3. Reinstall dc receptacle’s protective cover.
Engine Starting
Prior to engine start, ensure power cell charge is sufficient to provide an efficient engine start. Check DC
power cable for secure and correct installation prior to engine starting. Follow ground power engine starting
procedure as specified in vehicle operator’s manual.
NOTE
!
When all LED status indicator bars illuminate, both the converter and power
cells are supplying 24 Vdc power output for current demands above 60 amps.
CAUTION
!
Unplug ac power cord before starting engine with unit.
High Power Demand
High power demand is defined by a requirement of greater than 400 amps. Connect to aircraft ground power
receptacle. DC bus power should come on and aircraft voltmeter should indicate 28.5 Vdc to 23.5 Vdc (23
VCD minimum). If current demand is greater than 60 amps, converter output voltage will drop below 28.0
Vdc and LED status indicator lights will illuminate indicating current is being drawn from the power cells.
The greater the current draw, the quicker the LED status indicator will approach red. Note the LED status
indicator shows the status of the power cells.