
Programming Your Application
6-67
590+ Series DC Digital Converter
RAMPS
AUTO RESET
RAMP INPUT = X%
DRIVE ENABLED
DRIVE ENABLED
0%
DRIVE DISABLED
t
X%
100%
RAMP INPUT %
= RAMP INPUT X %
RAMP OUTPUT
0%
t
X%
100%
RAMP OUTPUT %
When AUTO RESET is ENABLED, ramp output resets to RESET VALUE each time the
drive is enabled. In this example RESET VALUE is 0.00%. It does not reset if the drive is
disabled.
EXTERNAL RESET
RAMP INPUT X%
EXTERNAL RESET ENABLED
0%
t
X%
RAMP INPUT %
100%
= RAMP I/P X%
0%
t
Y%
t
RAMP OUPUT %
100%
X%
The ramp input is set to X% at time t
0
. The ramp output will increase at the ramp rate.
While EXTERNAL RESET is ENABLED, the ramp output resets to RESET VALUE (Y%).
When EXTERNAL RESET is DISABLED, the ramp output continues to follow the input
signal.
MIN SPEED
DRIVE ENABLED (AND AUTO RESET ENABLED)
RAMP INPUT
0%
t
X%
RAMP INPUT %
100%
RAMP INPUT
RAMP OUTPUT %
MIN. SPEED = Y%
0%
t
NOTE: THE POLARITY OF SPEED SETPOINT DETERMINES THE DIRECTION OF MIN. SPEED
Y%
X%
100%
This figure shows the effect of setting MIN. SPEED above 0.00%. When the drive is enabled,
the ramp output cannot fall below the value set by MIN. SPEED. Notice the ramp rates are
used when changing the output from minimum speed to zero speed. Notice also that in this
example the ramp output only increases to X% since the ramp input signal is limited to X%.