Danfoss VLT Programming Manual page 148

Parameter Description
When low power or low speed is detected the motor is stopped, but the reference signal (f
monitored and because of the low pressure created, the controller will increase the reference signal to gain pressure. When the
reference signal has reached a set value f
The speed is set manually by an external reference signal (Remote Reference). The settings (parameter group 22-3*) for tuning of
the No Flow function must be set to default.
Configuration possibilities, overview:
No Flow detection (pumps only) Yes
Low speed detection
External signal
Pressure/Temperature
(transmitter connected)
Output frequency
NOTE
Sleep Mode will not be active when Local Reference is active
(set speed manually by means of arrow buttons on the LCP).
See 3-13 Reference Site.
Does not work in Hand-mode. Auto set-up in open loop
must be carried out before setting input/output in closed
loop.
22-40 Minimum Run Time
Range: Function:
10 s [0 - 600 s] Set the desired minimum running time for the
*
motor after a start command (digital input or
Bus) before entering Sleep Mode.
®
VLT HVAC Drive Programming Guide
p
(Pressure)
P
Set
f f
(Frequency)
Ref Out
f f
Ref / Out
f
Wake
t
1
No/Low Flow Sleep mode
detected activated
the motor restarts.
wake
Internal PI Controller
(1-00 Configuration Mode: Closed loop)
Sleep mode Wake up
Yes
Yes
Yes
No
®
MG.11.CB.02 - VLT is a registered Danfoss trademark
p
System
Time
f
Ref
f
Out
Time
P = P
Ref Wake
) from the external controller is still
ref
External PI Controller or manual control
(1-00 Configuration Mode: Open loop)
Sleep mode
Yes (except manual
setting of speed)
Yes
Yes
22-41 Minimum Sleep Time
Range: Function:
10 s [0 - 600 s] Set the desired Minimum Time for staying in
*
Sleep Mode. This will override any wake up
conditions.
Wake up
No
Yes
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