ABB ACS 400 User Manual page 99

Code Description
4013 PID SLEEP DELAY
Time delay for the sleep function, see Figure 39. If the ACS 400 output frequency is below a set level
(parameter 4014
4014 PID SLEEP LEVEL
Level for activation of sleep function, see Figure 39. When the ACS 400 output frequency falls below the
sleep level, the sleep delay counter is started. When the ACS 400 output frequency rises above the sleep
level, the sleep delay counter is reset.
4015 WAKE-UP LEVEL
Level for deactivation of sleep function. This parameter sets a process actual value limit for the sleep
function (see Figure 39). When the actual value falls below the limit, the sleep function is interrupted.
Wake-up level = %Ref. x (Param 4015) / 100
Note!
Wake-up level comparison is also inverted when error value is inverted using parameter 4005
ERROR VALUE INV
-
WAKE UP LEVEL
SLEEP LEVEL
parameter 4014
Figure 39 Sleep function.
Note! The proportional gain and integration time values are used to adjust the
responsiveness of the system. A low value for proportional gain and a high value for
integral time ensures stable operation, but provides sluggish response. Too large of a
proportional gain value or too short of an integral time can cause the system to become
unstable. To start, set Parameter 4001 PID Gain to 0.3. Set Parameter 4002 Integration
Time to 20 seconds. Start the system and see if it reaches the set point quickly while
maintaining stable operation. If not, increase PID Gain (4001) until the actual signal (or
drive speed) oscillates constantly. It may be necessary to start and stop the drive to
induce this oscillation. Reduce PID Gain (4001) until the oscillation stops. Set the value
to 0.4 to 0.6 times this value. Decrease the Integration Time (4002) until the feedback
signal (or drive speed) oscillates constantly. It may be necessary to start and stop the
drive to induce this oscillation. Increase Integration Time (4002) until the oscillation
stops. Set the value to 1.15 to 1.5 times this value. If the feedback signal contains high
frequency noise, increase the value of Parameter 4004 Derivative Filter until the noise is
filtered from the signal.
ACS 400 User's Manual
) longer than
SLEEP LEVEL
.
Actual value
Frequency
t =
SLEEP DELAY
d
t < t
d
, ACS 400 is stopped.
PID SLEEP DELAY
, parameter 4013
t
d
STOP START
Time
Time
89