Percussionaire IPV-2C - PDM Fault Logging and Detection

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NOTE: Pressure faults are triggered by a continuous pressure of more than
150 cmH₂O for more than 5 seconds during Wake and Active modes.
NOTE: If System Failure screen is displayed, remove batteries for 30 seconds. Replace
batteries (note that positive terminals face same direction) and wait 30 seconds until the
screen turns o. If POST check runs correctly, PDM may be used. If System Failure screen
recurs, contact an authorized Percussionaire® service center.
The software keeps track of several types of hardware and data faults. All faults are
logged in the microcontroller’s memory and are retained even if the batteries are
removed. If multiple faults happen within 10 seconds of each other, the PDM stops
normal operation and enters Fault mode. In this mode, a subset of the collected fault
information is displayed on the LCD. This data is intended for manufacturing and repair
use only.
The user can exit the Fault mode by removing and replacing the batteries. This resumes
normal operation of the PDM but does not erase the faults stored in memory or x the
problem that caused the fault.
The PDM has both hardware and software fault detection. This is a dedicated hardware
“watchdog” that runs on an independent clock source and can continue to operate even
if the main microprocessor’s clock fails or the microcontroller pauses in any way. The
independent fault detection is reset each time a valid pressure reading (free of hardware
and software errors) is obtained.
In addition to the hardware fault detection, the software also implements a fault
detection “watchdog”. This “watchdog” detects if a software task fails to complete within
the specied time, logs an error and resets the processor.
Fault Logging
Fault Detection