Alpha Technologies APU Control Module (ACM) - Manual (Page 24)

018-340-B0-001 Rev. A 24
5.0 System Self-Test and Maintenance
5.1 Self-Test
Generator testing can be initiated in four ways:
1. The ACM can be programmed to periodically run an automatic test (Default OFF).
2. A Self-Test can be commanded via status communications.
3. Momentary activation of the Engine Run command will cause the ACM to effectively run a
test. Note that this method is the least desirable because the Self-Test Fail alarm will not be
set if an alarm condition arises.
4. A one-minute automatic test is performed when the manual control switch is returned to
Auto from Stop. Generator testing consists of starting and running the generator for a
programmable period of time (the default test duration is 10 minutes). The ACM monitors
all engine-related signals and will declare a self-test as failed if any of the following alarms
activate during the test:
• Low Oil Pressure registered as a control fail
• Engine Over-temperature
• Engine Over-crank
• Low Fuel
• ACM Control Failure
• Low Ignition Battery
• Low DC Bus Voltage
The ACM will not start a self-test if the engine is disabled, the stop switch is asserted, or the
engine is already running.