Rockwell Automation 20A PowerFlex 70EC/700VC User Manual
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Digital Inputs
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Precharge Enable
This function is used to manage disconnection from a common DC bus.
If the 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 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.
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Digital Input Data Logic
Digital Input Data Logic performs logical operations on the condition of digital
inputs with that of data contained in a parameter. The output of the logical
operation performs the function (start, stop, preset speed, etc.) that is “assigned”
to the digital input. An example of an appropriate application for this function is
the temporary override of a conveyor sensor that is wired directly to a digital
input. In such a case, a controller could write the data to the drive over a network
to start a drive, and then reset the data after the conveyor load clears the sensor,
thus allowing the sensor to stop the next load.
When this feature is enabled through bit 9 (“DigIn DatLog”) of
[Compensation], parameter 56, the operation is performed. If the feature is
disabled, the functions assigned to the digital inputs will operate directly,
regardless of the data in the “Digital Input Data Logic” parameter.
The following diagram shows the logical operation. The condition of each
digital input is “ANDed” with the “ANDdata” from [DigIn DataLogic],
parameter 411, then “ORed” with the “ORdata” from [DigIn DataLogic]. The
result is fed to the assigned digital input function.
The logical result (output) for each string of operations for a digital input can be
viewed in the upper half of parameter 216 [Dig In Status].
When the feature is enabled, and the Input 6 Dedicated Enable Jumper is pulled,
the Data Logic function will still be performed on input 6, but will not interfere
with the dedicated hardware path to the gate drive circuit.
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Fast Stop
When this input is opened, the drive performs a “Fast Stop.” See "Stop
Modes" on
for a description of this stopping method.
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Speed/Torque Select 1, 2, and 3
These settings provide the ability to switch between different speed/torque
modes from digital input combinations. See "Speed/Torque Mode" on
for a complete description of these modes and the digital input combinations
that activate each mode.
AND
Dig In 1 Condition
In1 ANDdata
In1 ORdata
OR
Output to Assigned
DigIn function