Lenze MC1000 Series - Manual (Page 62)

58 13435742_EDBM101_v24
37 SLEEP DL (SLEEP DELAY)
This parameter sets the amount of time the drive must operate below the SLEEP
THRESHOLD (see Parameter 36 above) before the drive "goes to sleep" and brings
the motor to zero speed.
Example: SLEEP THRESHOLD is set to 15 Hz and SLEEP DELAY is set to 60
seconds. If the drive operates below 15 Hz for 60 seconds, the drive will "go to
sleep" and the motor will stop. The drive's display will indicate SLEEP, and the
drive will remain "sleeping" until the drive commanded to a speed equal to greater
than 17 Hz. At this point, the drive will "wake up" and ramp the motor up to the
commanded speed.
38
SLEEP BW (SLEEP BANDWIDTH)
This parameter allows the PID feedback signal to determine when drive should
"wake up" when operating in Sleep Mode. In process systems that utilize Integral
Gain (see Parameter 78), the drive may cycle in and out of Sleep Mode more often
than desired, due to the Integral function of the PID algorithm.
When SLEEP BANDWIDTH is used, the feedback signal must decrease or increase
(depending on whether the system is normal or reverse-acting) by the programmed
amount before the drive will "wake up". This parameter is set in PID units.
Example: In a normal-acting system, the PID set point is 50 PSI, SLEEP
THRESHOLD is set to 20 Hz, and SLEEP BANDWIDTH is set to 5 PSI. The drive
will enter Sleep Mode when the commanded speed drops below 20 Hz for the
time defined in SLEEP DELAY. The drive will wake up when the feedback signal
drops below 45 PSI (50 PSI set point minus 5 PSI bandwidth = 45 PSI), even if the
commanded speed is still below 20 Hz.
NOTE: If SLEEP BANDWIDTH is set to 0, this function is disabled, and the drive
will wake up when the commanded speed exceeds the SLEEP THRESHOLD plus
2 Hz, as described in Parameters 36 and 37.
39
TB5 MIN (TERMINAL TB-5 INPUT)
TB5 MIN selects the output frequency of the drive that will correspond to the
minimum analog speed reference input (0 VDC or 4 mA). This parameter is used in
conjunction with Parameter 40 - TB5 MAX to define a speed range that corresponds
to the analog speed reference input (0 - 10 VDC or 4 - 20 mA).
40
TB5 MAX (TERMINAL TB-5 INPUT)
TB5 MAX selects the output frequency of the drive that will correspond to the
maximum analog speed reference input (10 VDC or 20 mA). This parameter is used
in conjunction with Parameter 39 - TB5 MIN to define a speed range that corresponds
to the analog speed reference input (0 - 10 VDC or 4 - 20 mA).
Example 1: The drive is required to operate from 0 to 60 Hz in response to a 0-5
VDC speed reference signal (rather than the “normal” 0-10 VDC). Because TB5 MAX
is based on a 0-10 VDC (or 4-20 mA) signal, the drive will operate at half of the TB5
MAX value if it is given a 5 VDC signal. Therefore, setting TB5 MAX to 120 Hz will
cause the drive to run at 60 Hz when it is given a 5 VDC speed reference signal.
NOTE: The drive can be programmed for inverse operation so that as the speed reference
increases, the drive speed will decrease, and as the speed reference decreases, the drive
speed will increase. This is accomplished by setting TB5 MIN to the desired maximum
output frequency, and TB5 MAX to the desired minimum output frequency.