Rockwell Automation GV3000/SE AC Drive ControlNet Network Communication Board, M/N 2CN3000 - Manual (Page 58)

3-4 GV3000/SE AC Drive ControlNet Network Communication Option Board
3.5 Setting the Communication Loss Response (P.062)
Parameter P.062 defines how the drive responds when a loss of scheduled
communication is detected. This parameter can be written over the ControlNet
network.
When P.062 = 0 (IET fault), the drive will fault stop when loss of communication is
detected.
When P.062 = 1 (Hold last reference), the drive maintains the last reference until
communication is re-established and the programmable controller has completed one
scan to evaluate a new drive reference value.
If network communication is re-established, the drive will again follow the reference
and sequencing control inputs supplied by the network master. Note that if P.054
(Level Sense Start Enable) = ON and the start and stop inputs are on (1), the drive
may start.
When P.062 = 2 (Use terminal strip reference), the drive uses the terminal strip analog
input for the reference value if P.008 = 0. If P.008
≠ 0, the selected source will be used.
After communication is re-established and the programmable controller has
completed one scan to evaluate a new drive reference value, ControlNet will resume
control. Note that when using this setting, the terminal strip Stop input must be
maintained for the drive to run.
Note that if P.054 (Level Sense Start Enable) = OFF and the drive is stopped while in
this mode, it cannot be restarted until network communication is re-established or the
Control Source (P.000) is changed.
Also note that if P.054 (Level Sense Start Enable) = ON and the start and stop inputs
are on (1), the drive may start.
!
ATTENTION: This parameter allows you to configure the drive to
continue to run if a loss of network communication occurs. You must
provide some form of hardwired stop in case of communication loss,
since stopping the drive through the network might not be possible.
Failure to observe this precaution could result in bodily injury or damage
to, or destruction of, equipment.
!
ATTENTION: In volts/hertz regulation, if P.000 (Control Source) is set to
OP (Option Port), and P.062 is set to 1 (Hold Last Reference), and the
drive loses communication with the network, the drive will maintain the
last frequency command sent to it. Ensure that drive machinery, all
drive-train mechanisms, and application material are capable of safe
operation at the maximum operating speed of the drive. Failure to
observe this precaution could result in bodily injury.
ATTENTION: In vector regulation, if U.000 (Torque Reference Source)
is set to 2 (Option Port), and P.062 is set to 1 (Hold Last Reference), and
the drive loses communication with the network, the drive will no longer
be regulating speed. Instead, motor speed will vary according to the load,
up to the overspeed limit. Ensure that driven machinery, all drive-train
mechanisms, and application material are capable of safe operation at
the maximum operating speed of the drive. Failure to observe this
precaution could result in bodily injury.