Rockwell Automation 20B PowerFlex 70, PowerFlex 700 Reference Manual - Manual (Page 83)

Digital Inputs
Rockwell Automation Publication PFLEX-RM001H-EN-P - June 2013 83
This choice is made when the user wishes to link the input to the output, but
desires that no other functionality be assigned to the input.
The state of any digital input can be “passed through” to a digital output by
setting the value of a digital output configuration parameter ([Digital Out
x
Sel]) to “Input n Link”. The output will then be controlled by the state of the
input, even if the input is being used for a second function. If the input is
configured as “Not used” input function, the link to the input is considered
non-functional.
•
Power Loss Level (PowerFlex 700 only)
When the DC bus level in the drive falls below a certain level, a “power loss”
condition is created in the drive logic. This input allows the user to select
between two different “power loss” detection levels dynamically.
If the physical input is closed, then the drive will take its power loss level from
[Power Loss Level]. If the physical input is open (de-energized), then the drive
will use a power loss level designated by internal drive memory, typically 82%
of nominal.
If the input function is not configured, then the drive always uses the internal
power loss level. This input function is used in PowerFlex 700 drives only. In
PowerFlex 70 drives, the power loss level is always internal and not selectable.
•
Precharge Enable (PowerFlex 700 only)
This input function is used to manage disconnection from a common DC
bus.
If the physical input is closed, this indicates that the drive is connected to
common DC bus and normal precharge handling can occur, and that the
drive can run (start permissive). If the physical input is open, this indicates
that the drive is disconnected from the common DC bus, and thus the drive
should enter the precharge state (precharge relay open) and initiate a coast
stop immediately in order to prepare for reconnection to the bus.
If this input function is not configured, then the drive assumes that it is always
connected to the DC bus, and no special precharge handling will be done.
This input function is used in PowerFlex 700 drive only. In PowerFlex 70
drives, the drive assumes it is always connected to the DC bus.
Digital Input Conflict Alarms
If the user configures the digital inputs so that one or more selections conflict
with each other, one of the digital input configuration alarms will be asserted. As
long as the Digital Input Conflict exists, the drive will not start.
These alarms
will be automatically cleared by the drive as soon as the user changes the
parameters so that there is an internally consistent digital input configuration.