Rockwell Automation FlexPak 3000 Digital DC Drive Version 4.3 - Manual (Page 151)

Troubleshooting the FlexPak 3000 Drive 13-19
13.6 Setting Reversed Tachometer or Reversed Encoder
Lead Detection
The FlexPak 3000 drive includes an algorithm for detecting reversed speed feedback
wiring. The logic verifies that the difference between the speed reference and the
speed feedback is greater than the threshold set by
TACH LEAD FLT THRESH (P.227) for
the amount of time set by TACH LEAD FLT DELAY (P.228). When the threshold is greater
than the difference for the specified delay, and the speed reference and speed
feedback are opposite in polarity, a
REVERSED TACH LEADS fault is generated
(fault F00014).
Fault F00014 can also be caused by an overhauling load, improper drive tuning, or a
tachometer or encoder loss.
The tachometer lead fault parameters have default values that are set so that reversed
tachometer lead detection is effectively disabled. You must empirically determine
values for these parameters so that reversed tachometer or encoder wiring can be
detected without generating nuisance faults.
The ability to check for reversed tachometer lead faults is useful for machine
manufacturers that require their equipment to be disassembled for shipping and
reassembled and rewired at a customer site.
This option is not available for AC tachometers.
TACH LEAD FLT DELAY (P.228)
The amount of time
that parameter P.227
(
TACH LEAD FLT
THRESH ) must be
exceeded before a
REVERSED TACH
LEADS fault (F00014)
is generated.
Parameter Range: 0 to 32767 msec
Default Setting: 10000 msec
Parameter Type: Tunable
OIM Menu Path(s): Additional Parameters (listed by parameter number)
TACH LEAD FLT THRESH
(P.227)
The threshold after
which a
REVERSED
TACH LEADS fault
(F00014) is
generated.
Parameter Range: 0.0 to 250.0% of TOP SPEED
Default Setting: 200.0%
Parameter Type: Tunable
OIM Menu Path(s): Additional Parameters (listed by parameter number)
A REVERSED TACH LEADS fault is generated if the difference between the speed
reference and speed feedback is greater than this value for at least the amount of
time set by
TACH LEAD FLT DELAY .