4 normal apu shutdown, 5 abnormal apu shutdown, Table 1-1 normal mode crank cycle – Alpha Technologies AlphaGen 5.0kW Auxiliary Power Unit User Manual

Page 20: System overview, Abnormal apu shutdown

1. System Overview

031-132-B0-001 Rev. A

1.5

Generator Modes of Operation, continued

1.5.4. Normal APU Shutdown

The ECM will initiate a normal APU shutdown when AC line is qualified, DC

bus alarm is not active, the 12 minute cool-down period has elapsed, and the

Engine Run command is not active. Otherwise, the ECM will continue to run the

APU until the above conditions are met or a major alarm occurs. Also, the APU

will run for a minimum of 30 minutes if started due to low DC Bus voltage.

1.5.5. Abnormal APU Shutdown

The ECM will immediately shutdown the APU under the following conditions:

Major alarm

Activation of manual engine stop switch

Receipt of software engine stop command

General generator failure

&UDQN &\FOH

8hx

(

8hxvt

@tvr

$Ãrp $Ãrp $Ãrp $Ãrp $Ãrp $Ãrp $Ãrp $Ãrp

$Ãrp

Qhr

Ãphx

"Ãrp "Ãrp %Ãrp "Ãrp "Ãrp %Ãrp "Ãrp "Ãrp

@tvr

Prphx

6yh

Table 1-1 Normal Mode Crank Cycle