TI3500 GPU-24
18
3
Operating Procedures
Removing DC Power Supply From Aircraft or Vehicle
Remove dc power cable GPU connector from aircraft or vehicle.
1.
Remove dc power cable connector from TI3500 GPU-24 (if necessary).
2.
Reinstall dc receptacle’s protective cover.
3.
Low Power Demand
Low power demand is defined by a requirement of 50 amps or less. Connect dc power to aircraft ground
power receptacle. DC bus power should come on and aircraft voltmeter should indicate 28.5 Vdc to 28 Vdc.
If aircraft power demand is less than 50 amps converter output will remain at 28.5 Vdc (only one GREEN LED
status indicator bar will illuminate). If aircraft power demand exceeds 50 amps converter voltage output will
decrease and two or more LED status indicator bars will illuminate.
High Power Demand
High power demand is defined by a requirement of over 50 amps. Connect to aircraft ground power receptacle.
DC bus power should come on and aircraft voltmeter should indicate 27.5 Vdc to 23.5 Vdc. If current
demand greater than 50 amps, converter output voltage will drop below 28 Vdc and two or more LED status
indicator bars 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.
NOTE
!
When all LED status indicator bars illuminate, both the converter and
power cells are supplying 24 Vdc power output for current demands above
50 amps.
Engine Starting
CAUTION
!
Unplug ac power cord before starting engine with TI3500 GPU-24
Prior to engine start, ensure power cell charge is sufficient to provide an efficient engine start.
Figure 3.10.5 Starting Fire Scout with
TI3500 GPU-24
Figure 3.10.6 Starting Vehicle with
TI3500 GPU-24
