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ANALOG VELOCITY CONVERSION FACTOR
- This parameter allows
setting a gain relating commanded velocity in user units / second to
the analog input value in volts. The figure shows a value of 0.542
inches / volt. Thus, for each volt of change at the analog input, the
commanded velocity would change by .542 inches / second.
Note: This parameter can be a negative value, if desired.
ANALOG ZERO SETPOINT
- This parameter allows the user to enter
an offset for the voltage-to-velocity conversion. The figure shows a
value of 1.999 volts. Thus, an analog input signal of 1.999 volts
would produce a command velocity of zero. This parameter and the
conversion factor allow complete definition of a range of velocity
command values corresponding to an analog input signal range.
ANALOG DEADBAND
- This parameter allows the user to enter a
voltage range around the setpoint which will correspond to a
command of zero velocity. In the figure, a value of 0.100 volts is
programmed. This means that if the analog input voltage is withing
0.100 volts of the setpoint of 1.999 volts, the commanded velocity
will be zero.
THRUST CONTROL
- To use Analog Input Velocity Control Mode for
thrust control, do the following:
•
An analog signal corresponding to actual thrust must be provided to
the indexer.
•
The analog offset (setpoint) should then be programmed to a value
corresponding to the desired thrust.
•
The conversion factor then essentially sets the "gain" of the
response to errors in thrust.
•
The deadband parameter can be used to prevent "hunting" around
the desired thrust setpoint.
•
PLC compare operations and other logic can be utilized to control
the exit condition.
OUTPUT/FLAG CONTROL
This group of instructions allows control of the physical outputs or
internal bit flags from within the sequential motion program.
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