Allen-Bradley PowerFlex 70 Reference Manual page 102

Faults
102
The fault queue will be a first-in, first-out (FIFO) queue. Fault queue entry #1
will always be the most-recent entry (newest). Entry 4 (8) will always be the
oldest. As a new fault is logged, each existing entry will be shifted up by one (i.e.
previous entry #1 will move to entry #2, previous entry #2 will move to entry #3,
etc.). If the queue is full when a fault occurs, the oldest entry will be discarded.
The fault queue will be saved in nonvolatile storage at power loss, thus retaining
its contents through a power off - on cycle.
Fault Code/Text [Fault Code 1-x]
The fault code for each entry can be read in its respective read-only parameter.
When viewed with a HIM, only the fault code is displayed. If viewed via a DPI
peripheral (communications network), the queue is not accessed through
parameters, and a text string of up to 16 characters is also available.
Fault Time [Fault 1-8 Time]
PowerFlex drives have an internal drive-under-power-timer. The user has no
control over the value of this timer, which will increment in value over the life of
the drive and saved in nonvolatile storage. Each time the drive is powered down
and then repowered, the value of this timer is written to [Power Up Marker],
parameter 242.
The time is presented in xxx.yyyy hours (4 decimal places). Each increment of 1
represents approximately 0.36 seconds. Internally it will be accumulated in a
32-bit unsigned integer with a resolution of 0.35 seconds, resulting in a rollover
to zero every 47.66 years.
The time stamp value recorded in the fault queue at the time of a fault is the value
of internal drive under power timer. By comparing this value to the [PowerUp
Marker], it is possible to determine when the fault occurred relative to the last
drive power-up.
The time stamp for each fault queue entry can be read via the corresponding
parameter. Time comparisons of one fault to the next and/or with [PowerUp
Marker] are only meaningful if they occur less than or equal to the rollover range.
Resetting or Clearing a Fault
A latched fault condition can be cleared by the following:
1. An off to on transition on a digital input configured for fault reset or stop/
reset.
2. Setting [Fault Clear] to "1."
3. A DPI peripheral (several ways).
4. Performing a reset to factory defaults via parameter write.
5. Cycling power to the drive such that the control board goes through a
power-up sequence.
Rockwell Automation Publication PFLEX-RM001H-EN-P - June 2013