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3.20 Main Menu - Application Functions - Group 22
This group contains parameters used for monitoring VLT
®
HVAC Drive applications.
22-00 External Interlock Delay
Range:
Function:
0 s
*
[0 - 600
s]
Only relevant if one of the digital inputs in
parameter group 5-1* has been programmed for
External Interlock
[7]. The External Interlock Timer
will introduce a delay after the signal has been
22-00 External Interlock Delay
Range:
Function:
removed from the digital input programmed for
External Interlock, before reaction takes place.
22-01 Power Filter Time
Range:
Function:
0.50 s
*
[0.02 - 10.00
s]
Sets the time constant for the filtered
power readout. A higher value will give
a more steady readout but a slower
system response to changes.
3.20.1 22-2* No-Flow Detection
Detection
timer
Low speed
detected
Low Power
detected
Warning
Alarm
External
sleep mode
command
Min run
timer
Min sleep
timer
Sleep
mode
Cascade
controller
(destaging
command)
speed detection
Sleep mode
Off
No flow/low
130BA252.15
1
P 22-22
P 22-24
1
P 22-40
P 22-41
P 22-21
P 25-26
P 22-23
The frequency converter includes functions for detecting if the load conditions in the system allow the motor to be
stopped:
*Low Power Detection
*Low Speed Detection
One of these two signals must be active for a set time (
) before selected action takes place. Possible
actions to select (
): No action, Warning, Alarm, Sleep Mode.
No Flow Detection:
This function is used for detecting a no flow situation in pump systems where all valves can be closed. Can be used both
when controlled by the integrated PI controller in the frequency converter or an external PI controller. Actual configuration
must be programmed in
.
Configuration mode for
-
Integrated PI Controller: Closed Loop
-
External PI Controller: Open Loop
Parameter Description
VLT
®
HVAC Drive Programming Guide
146
MG.11.CC.02 - VLT
®
is a registered Danfoss trademark
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